Mit-xxx Visual BASIC for Engineeringweb.acd.ccac.edu/~dwolf/files_to_download/RBT-225 - Dan Wolf Dec… · • Manufacturing and process control (PLCs as in RBT-235) Medical Robotics

1

Robotics in Industry - RBT-225

FALL 2016

Instructor: Dan Wolf

[email protected]

[email protected]://web.acd.ccac.edu/~dwolf/

Revised: 11/28/2016

WELCOME!

2

Week #1 - Introduction

Agenda :

1. Introductions

2. Course Formalities

Lab Assignment:

Lab_1_BasicStamp_Sensors.doc

3

Prior-Experience Evaluation

This is a very quick NON-CREDIT pre-test to allow me to

understand your current knowledge and capabilities.

Using the three electronic components, draw a schematic that will

allow the switch to energize the +5volt coil of the relay so that it

turns on the +24volt lamp.

24V Lamp

NO

NC

COMMON+5V

Coil

4

Course Introduction

This course offers an introduction to robotics, including motive power

elements, computer control, safety, work cells and maintenance. A

history and classification of robots is included. Programming,

calculation of robotic motion, electric and mechanical principles in a

Computer Integrated Manufacturing (CIM) environment are

studied.

The fact is, that civilization requires slaves. The Greeks were quite

right there. Unless there are slaves to do the ugly, horrible,

uninteresting work, culture and contemplation become almost

impossible. Human slavery is wrong, insecure, and demoralizing. On

mechanical slavery of the machine, the future of the world depends.

Oscar Wilde

5

Computer-Integrated Manufacturing

Computer-Integrated Manufacturing (CIM) is the manufacturing approach of using computers

to control the entire production process thus allowing individual processes to exchange

information with each other and initiate actions. Through the integration of computers,

manufacturing can be faster and less error-prone, although the main advantage is the ability to

create automated manufacturing processes. Typically CIM relies on closed-loop control

processes, based on real-time input from sensors. It is also known as flexible design and

manufacturing. CIM is much more than simply automating a series of manual operations.

6

Student Information

1. Name

2. Student ID Number

3. Phone Number

4. Alternate Phone Number

5. Do you have any hardware or electronics experience?

What areas?

6. What is your major? Is your major a 2 or 4 year program?

7. What do you already know? Word, Excel, PP, Mathcad, HTML

8.c. What is your expected graduation date?

9. Your EMAIL address

7

Introductions

1. Introduction to the Instructor

2. Student Introductions

a) Name

b) Where do you work or what is your degree?

c) Why are you taking this class?

8

Administrative Information

1. Grading

2. Syllabus

3. Questions?

9

Unit / Lab Assignments

See the Syllabus

10

Maximize Your Time

Do not get behind !

You will need the entire scheduled class time each week

11

Mini-Assignment #1 – due next week

Questions to ask of two other students:

1) Name

2) Degree

3) Name of Pet, hobby, or interest.

4) Employment

5) What do you want to learn from this class?

12

Industrial Robots

• Material Handling, Processing Operations, Assembly & Inspection

• Performing in hazardous conditions

• Security

• Manufacturing and process control (PLCs as in RBT-235)

Medical Robotics

• Surgery

• Bionic prosthetics (arms and legs)

• Drug dispensing

• Medical Laboratories (automating tests & analysis)

• Carriers (for food, documents, and medicines)

Non-traditional

• Domestic Robots

• Self-driving automobiles (and passenger mass-transit)

• Nano-robots (still at an early R&D stage)

The World of Robots

13

1. Material Handling

• Robotic handling operations (38%)

2. Processing Operations

• Robotic Welding (29%)

• Robotic Dispensing (4%)

• Robotic Processing (2%)

3. Assembly and Inspection

• Robotic Assembly (10%)

INDUSTRIAL ROBOTSTHE 5 MOST POPULAR APPLICATIONS

14

Robot Machining Video

Grinding and polishing of hip implants with a KUKA

robot:

https://www.youtube.com/watch?v=gO_8spCu29M

15

Robotic Applications

16

Sensors & Relays we will be using

1.BRN

3.BLU

4.BLK

2.WHI

CA18CLN12PAProximity Sensor

+V

Gnd

The datasheets for these are located on the class website.

Detects the presence

of an object.

Detects the absence of

an infrared light source.

.

DPDT Relay, +12V

coil

17

Proximity Sensor

1.BRN

3.BLU

4.BLK

2.WHI

CA18CLN12PAProximity Sensor

+V

Gnd

The datasheet for this is located on the class website.

Detects the presence of an object

using capacitance as the sensing

mechanism.

It will detect an object that gets

very close to it (3-12mm).

Detects the presence of an object.

18

Photoelectric Sensor


Detects the absence/presence of an

infrared light source (within 2 m).

E3F2-R2C4

Infrared

Photoelectric

Sensor

Reflector

Object will break the

infrared light beam

19

BTA1-2C 12V Relay


DPDT – Double Pole, Double Throw

N.O. – Normally Open Contacts

N.C. – Normally Closed Contacts

Contacts are rated for 10A at 120VAC

+12V Coil

20

Basic Electronic Refresher

E

I R

𝐸 = 𝐼𝑅 ∗ 𝑅 𝐸𝑇𝑜𝑡𝑎𝑙 = 𝐸𝐿𝐸𝐷 + 𝐸𝑅 5𝑉𝑜𝑙𝑡 = 2.0 𝑉𝑜𝑙𝑡 + 3.0 𝑉𝑜𝑙𝑡 𝐸𝑅 = 3.0 𝑉𝑜𝑙𝑡 Assume: ILED = IR = 5mA

𝑅 = 𝐸𝑅𝐼𝑅

= 3.0 𝑉𝑜𝑙𝑡

0.005= 600 𝑜ℎ𝑚

21

Classroom Safety Rules

1. No one shall ever be within the reach of the robot arm

during operation.

2. Someone shall always be assigned to remain at the

controller in order to emergency halt the robot.

3. The motor power switch shall always be off before anyone

can enter the robot space.

4. All software programs and hardware connections shall be

peer reviewed by a second person before being tested.

5. Always keep your hands away from the robot joints (pinch

points).

22

Equipment Safety

1. Do not connect any equipment to the controller box without first getting

approval from the instructor.

2. Do not apply power to the robot arm or power supplies without first

getting approval from the instructor.

3. The motor power switch shall always be off before anyone can enter the

robot space. (34” circle around the robot)

4. Always HOME the robot arm when you first start.

5. Do not leave any of the axes under mechanical strain for any length of

time. Especially, do not leave the gripper grasping an object indefinitely.

23

Equipment Rules

1.The gripper must always be in the open position

unless a program is actually running.

2.Do not leave the arm in a loaded position unless a

program is actually running.

3.The motor power switch shall always be off before

anyone can make any wiring changes.

4.All hardware connections shall be peer reviewed

by a second person before power is applied.

24

Lab Guidelines

1.Lab work should be in teams of two whenever

possible.

2.Each student should alternate as the “lead” for the

hardware and “lead” for the software.

• If you allow your partner to do most of the

software or hardware, you will be cheating

yourself out of the learning experience.

3. You will work on Lab#1 tonight.

25

Neatness counts

Make sure your connections, wire routing, and equipment

placement is neat and organized!

Bad Good

26

Lab #1 Interface Document

This is due at the end of the course and should include the

following schematics:

1) Standard SPST switch to a relay

2) Proximity Sensor to a Relay

3) Photo Sensor to a Relay

4) Relay contacts to an LED

5) Relay connected to a ScorBot Input

6) Relay (or normal SPST switch) to a BasicStamp digital input

7) ScorBot output to an LED.

8) ScorBot output to a relay coil

9) ScorBot output to a BasicStamp input

10) BasicStamp output to a ScorBot input

11) BasicStamp digital output to an LED (both driving and sinking)

12) BasicStamp digital output to drive a relay using a transistor.

13) BasicStamp digital output to drive a relay using a opto-isolator

27

Motivational Comment

Equipment problems and uncertainties are undesired

but normal in industry. Engineers and technicians are

paid to “out-think” the problems and then provide

solutions while staying focused and (realistically)

optimistic.

We will be experiencing this during the lab

experiments.

28

The End

29

Week #2 – Intro & Relays

Agenda :

1. Basic Stamp Software Commands & Programming

2. Chapter 1:

Burden Rate: Page 12-13

Setup time

Part cost

Cycle Time

Velocity Calculations Page 41

Robot Safety Guidelines: see page 42 – 46

Work Envelope

Lab Assignment:

Lab_2_BasicStamp_Relays.doc (due in two weeks)

30

Cost of Operations (Page 12 to 14 in the textbook)

1. Burden Rate is the hourly cost to the manufacturer for a given machine and

includes all costs associated with that machine (but not setup cost).

2. Lot Size is the amount of parts being made for this order.

3. Setup time is the length of time required to prepare a machine for production.

4. Part Production Cost is the cost of running the machine for one part. It does

not include setup costs or profit.

5. Total Finished Cost per Part is the total cost to make one part, including

setup, production, and profit costs.

6. Production Cost per Lot and Total Finished Cost per Lot can also be

calculated.

7. Setup Cost is the cost of the setup time (Setup Time * Burden Rate).

8. Setup Cost per Piece is the percentage of total setup cost that is applied to a

single piece (Total Setup Cost / Lot size).

31

Compute the cost of setup time

Assume:– a burden rate of $120 per hour

– The total setup time for the machine is 1.5 hours

– Lot size of 400 pieces

Total Setup Cost = Burden Rate * Machine Setup Time

= $120 * 1.5 Hours = $180

Setup Cost per Piece = Total Setup Cost / Lot Size

= $180 / 400 = 0.45 $ per piece

32

What are the production costs?

Assume:– a burden rate of $120 per hour

– A required markup of 27%

– The setup cost per part is $1.05

– The work cell can produce 8 parts every 12 minutes

Nbr of parts built per Hour =(60min/12min) * 8 = 40 parts per hour

Part Production Cost = Burden Rate / 40 pph = $120 / 40 = $3.00 Production cost per part

Note: Part Production Cost does not include setup cost.

Total Finished Cost per Part = (Part Production Cost + Setup Cost per Part) * 1.27

= ($3.00 + $1.05) * 1.27% = $5.14

33

1. Velocity is the rate which the robot can move each axis.

2. The maximum velocity of the ScorBot arm is 330mm/Sec (13”/Sec).

3. The maximum velocity of an axis must be reduced whenever it is carrying a load.

The percent reduction is based on the load weight.

• Calculate the velocity for the ScorBot arm if it must move a 0.5 pound

load at a 30% speed reduction:

Velocity for 0.5lb Load = 13”/Sec * 0.70% = 9.1”/Sec

• Calculate the time for the 0.5 pound load across 80 inches:

Time for 0.5lb Load = Distance / Velocity = 80 / 9.1” = 8.79 seconds

Question: Is there a reduced velocity rating for the ScorBot arm when it is

carrying a load? Or is 13”/Sec the max velocity when it has a 2.2 Lb load?

Velocity (Page 41 in the textbook)

34

Cycle Time (page 42 in the textbook)

Cycle Time = Time to move one step

Total Cycle Time = Time required for all steps

Assume the following arm sequence:

a) 38” movement of empty arm to first pickup position (𝑇𝑒𝑚𝑝𝑡𝑦)

b) Four second delay for the part to arrive (𝑇𝑑𝑒𝑙𝑎𝑦)

c) 24” movement of the fully loaded arm to the second position (𝑇𝑓𝑢𝑙𝑙)

d) Each of six programmed points requires 0.1 seconds (𝑇𝑝𝑝)

e) Gripper open or close requires 0.2 seconds (𝑇𝑔𝑚)

f) The velocity of the empty arm is 60” per second with a 20%

reduction at maximum payload.

Total cycle time = 𝑇𝑐𝑦𝑐𝑙𝑒 = 𝑇𝑓𝑢𝑙𝑙 + 𝑇𝑒𝑚𝑝𝑡𝑦 + 𝑇𝑑𝑒𝑙𝑎𝑦 + (6 ∗ 𝑇𝑝𝑝) + (2 ∗ 𝑇𝑔𝑚)

35

Find total cycle time (see previous slide)


𝑇𝑒𝑚𝑝𝑡𝑦 = 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒

𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦=

38"

60 𝑖𝑛/𝑠𝑒𝑐= 0.63 second

Velocity at maximum payload = Empty Velocity * 0.8 = 60 in/sec * 0.8 = 48 in/sec

𝑇𝑓𝑢𝑙𝑙 = 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒

𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦=

24"

48 𝑖𝑛/𝑠𝑒𝑐= 0.5 second

𝑇𝑑𝑒𝑙𝑎𝑦= 4 seconds


= 0.5 + 0.63 + 4 + 6 ∗ 0.1 + (2 ∗ 0.2)= 6.13 seconds

36

Work Cell Safety Guidelines

1. The maximum reach of the robot arm determines the safe working distance.

2. An “In-Use” warning light shall be located where it is visible by nearby personnel.

3. No un-neccesary hardware shall be within reach of the robot arm.

4. Workplace barriers shall surround the work cell.

5. Emergency stop switches shall be located at strategic points around the work cell.

6. Signs shall be located at strategic points around the work cell indicating movement

could occur at any time.

7. A “Lock-out/Tag-out” system shall be provided to allow a worked to disable the

system vie his personal padlock (or key or equivalent).

8. Pages 44 to 46 of the textbook contain excellent guidelines and things to

remember.

37

Work Cell Safety

38

Lab Reports - An Overview

The title page should include your name, chapter# and lab title.

Software printouts and schematics may be referenced in the

text.

Discuss as many of the new lab concepts as possible.

Optional work is highly encouraged and required for grades

above 89%.

One of the worst things to do is get behind on the labs.

Additional grading details are explained in the syllabus.

39

Lab Report Format

INTRODUCTION:

Provide an overview of the topics that are involved in the lab.

BODY:

List and discuss each experiment.

Include data and explain/discuss your calculations.

Optionals should be identified.

CONCLUSION:

Summarize each new instruction or concept.

PRINTOUTS:

Include software, hardware and layout diagrams.

40

Lab Report Schedule and Grading

• Lab reports are due two weeks after the last

work night for that lab.

• I require a majority of the labs before I will

grade them.

• I will return the graded labs to you the week

after I grade them.

• You must inform me in advance if your lab

report will be late.

41

Spell & Grammar Check Reminder

Are you using MS-Word for your labs?

Are you using the Spell Checker and Grammar

Checker?

To Configure:

Tools | Options | Spelling and Grammer

To run:

F7

42

Electronics Review before Lab 2

The relay coil current is IRELAY = 100mA, transistor gain is 50,

and VBE is 0.6V so:

VR = 5V – 0.6V = 4.4V

IR = 100mA / 50 = 2mA

R = 4.4V / 2mA = 2200 ohms (use a 2K)

43

Basic Stamp Introduction

The BASIC Stamp is a microcontroller developed by Parallax,

Inc. which is easily programmed using a form of the

BASIC programming language. It is called a “Stamp” simply

because it is close to the size of an average postage

stamp.

Downloadable from the course website:

Basic Stamp Programming Manual.pdf

Programming_the_Basic_Stamp.doc

What is a Micro-controller.pdf

44

Basic Stamp Information

We are using: “Board of Education” board which has a BS2 Basic

Stamp controller.

• Mechanically interlocked power supply to prevent dual connection of

wall-pack and 9-volt battery

• DB9 connector for BS2-IC programming and serial communication

during run-time

• P0 - P15 I/O pins, Vdd and Vss connections brought adjacent to

1.375 x 2 in ( 35 x 51 mm) breadboard area

• Female 10-pin dual row connector for optional AppMods

• On-board regulator delivers up to 1 amp of power for larger projects

• Jumper selection of servo power: regulated (Vdd) or unregulated

(Vin)

• Three-position power switch allows various powering options for

programming without providing power to servo connectors

45

Basic Stamp 2 Details (BS2)

• Processor Speed: 20 MHz; ~4,000 PBASIC instructions/sec

• PBASIC Commands: 42

• Package: 24-pin DIP

• I/O pins: 16 + 2 dedicated serial

• RAM Size: 32 Bytes (6 I/O, 26 Variable)

• EEPROM (Program) Size: 2 KBytes; ~500 PBASIC instructions

• Voltage requirements: 5.5 to 15 VDC (Vin), or 5 VDC (Vdd)

• Current requirements: 3 mA Run, 50 μA Sleep

• Source/Sink Current per I/O: 20 mA / 25 mA

• Source/Sink Current per unit: 40 mA / 50 mA per 8 I/O pins

• Communication: Serial (9600 baud for programming)

• Dimensions: 1.20 x 0.63 x 0.15 in (30.0 x 16.0 x 3.81 mm)

• Operating temp range: -40 to +185 °F (-40 to +85 °C)

46

Basic Stamp I/O Specifications

Input Impedance is 1M ohm

So a 5 Volt input level will result in a:

5V / 1M = 0.000005 = 5uA input current

The input for a logic low must be less than 1.4 Volts

The input for a logic high must be greater than 1.4 Volts

The Basic Stamp CONFIGPIN command allows this to be changed.

The BasicStamp inputs do not contain pull-up or pull-down resisters so they

must be connected to either 0V or +5V if they are being read.

Output current is: Source = 20mA or Sink 25mA per I/O pin

Across all I/O pins, not to exceed: Source = 40mA and Sink = 50mA

47

Two methods of interfacing to a digital input

What size resister is required?

Input impedance is 1M ohm so when the switch is open, the input will

source up to 5uA thru the resister (5V/1M = 5uA).

5uA * 1K = 5mV which is well below the input threshold of 0.5 Volt for a

logic low.

5uA Current flow

48

The End

Please read Chapter 2 prior to the class next week.

49

Week #3 – ScorBot Intro & Positions

Agenda :

1. ScorBot Positions and Run Program

2. Chapter 2

Robot Arm Geometries

Drive Systems Page 74

Control Techniques – Page 87

Sensors – Page 88

Potentiometers versus encoders

Resolvers (Synchros) – Page 95

Closed / Open-loop

Path Control

Lab Assignment:

Finish Lab #1 & 2 otherwise move ahead to Lab#3

a) Goto Position above destination @

Position #1

b) Slowly lower arm to item #1 @ Position@2

c) Close gripper

d) Raise arm back to Position#1

e) Move to Position#3 above the destination

f) Lower arm down to Position#4

g) Open gripper

h) Raise arm back to Position#3

i) Goto Home Position#5

50

In general, robot arms have three movements (up-down, in-out, side-to-

side). In addition, they can have as many as three additional wrist

movements on the end of the robot's arm: yaw (side to side), pitch (up

and down), and rotational (clockwise and counterclockwise).

Degrees of Freedom

The human wrist can

perform 22 different

movements!

51

X, Y, and Z are referenced to the tool plate.

Pitch, Yaw, and Roll are referenced to the wrist.

The six arm motions

Y-Axis

-LEFT & +RIGHT

via rotating the base

X-Axis

-IN towards the base

+OUT away from the base

Z-Axis

-DOWN and +UP

52

Accuracy versus Precision

53

• Six Axis, x, y, and z axis plus yaw (side to side), pitch (up and

down), and rotation

• Very flexible

• Load Capacity: 3-600kg

• Articulated Arm or Gantry

1) Configurations: Coordinate / Cartesian

54

2) Configurations: SCARA(Selective Compliance Assembly Robot Arm)

• Four axis: x, y, z, and wrist/twist about the z-axis (vertical)

• Large workspace, High Speed with very good repeatability,

not so good in the vertical axis

• Moderate Load Capacity: 1-20 kg

55

3) Configurations: Delta (Spider)

• Four axis: x, y, z, and

wrist/twist about the z-axis

(vertical)

• Restricted workspace, Very

high speed, not so good in

the vertical axis

• Lowest Load Capacity: 1-3 kg

56

Types of Path Movements

• Point-to-Point Path: The points

are specified but not the path.

• Controlled Path: More precise

than point-to-point because it

ensures a specific path is taken.

• Continuous Path: An extension

of point-to-point providing very

smooth movements.

57

Arm Movement Sequence

NO

YES

58

Power Sources

• Pneumatic – typically low-pressure air for low

weight carrying.

• Hydraulic – typically high-pressure oil for medium

to high force/weights, smoother than pneumatics,

potential environmental issues.

• Electrical - most common, better motion control,

safer because they can be shut down quickest.

59

Hardware Concepts

▪ SCORBOT Arm

➢ 12V Motors

➢ Encoders

➢ Gears

➢ Limit Switches

➢ Control Box

▪ Transmission ratio

▪ RPM Ratio

▪ Resolution ratio

▪ Encoders

60

Hardware Concepts – The Arm

▪ SCORBOT Arm

➢ 12V Motors

➢ Encoders

➢ Gears

➢ Limit Switches

➢ Control Box

61

ScorBot Arm Specifications

▪ Axis 1: Base Rotation 310 degrees

▪ Axis 2: Shoulder Rotation +130 Degrees / -35 Degrees

▪ Axis 3: Elbow Rotation +- 130 Degrees

▪ Axis 4: Wrist Pitch +- 130 Degrees

▪ Axis 5: Wrist Roll Unlimited

▪ Axis 6: GRIPPER Open/Close + Measurement of gripper opening

▪ Maximum Working Radius: 61mm (24.4")

▪ Gripper Opening: 75mm (3") without rubber pads - 65mm (2.56") with rubber pads

▪ Maximum Work Load: 1kg (2.2 Lb)

▪ Transmission: Gears, Timing Belts and Lead Screw

▪ Actuators: 6 DC Servo Motors with Closed-Loop Servo Control

▪ Feedback: Optical Encoders on All Axis

▪ Hard Home: Fixed Reference Position on all Axes

▪ Repeatability: +- .05mm (+- 0.02")

▪ Maximum Speed: 330mm/Sec. (13"/Sec)

▪ Weight: Robot Arm: 11kg (24 Lb) - Controller: 5kg (11 Lb)

62

Torque Calculations

▪ Torque = L(feet) * F(pounds)

▪ Assume:▪ Downward force at W4 is 10 pounds

▪ The combined length of L1 and L2 is 30 inches.

T = L * F

Torque at M1 must be

2.5ft * -10 lbs = -25 ft-lbs

in order to hold the arm level.

63

Gear Ratio (GR)

In this example, gear a turns 3 times for each turn of gear b:

GR=𝑅𝑎

𝑅𝑏

Ra = radius of gear attached to the motor shaft

Rb = radius of gear attached to the robot base

Ra=20mm, Rb=60mm

GR = 𝑅𝑎

𝑅𝑏=

20

60=

1

3

64

Transmission Ratio (𝑇𝑎𝑏)

In this example, gear a turns 3 times for each turn of gear b:

𝑇𝑎𝑏 =1

𝐺𝑅or 𝑇𝑎𝑏 =

𝑅𝑏

𝑅𝑎: 1

𝑇𝑎𝑏 = Transmission ratio from gear a to gear b

Ra = radius of gear attached to the motor shaft

Rb = radius of gear attached to the robot base

Ra=20mm, Rb=60mm

𝑇𝑎𝑏 = 60

20:1 = 3:1

65

If gear B is larger than gear A then the speed of gear B is

reduced while the torque of gear B is increased.

or

If gear B is smaller than gear A then the speed of gear B is

increased while the torque of gear B is decreased.

Transmission Ratio (𝑇𝑎𝑏)

66

RPM Ratio

In this example, gear a will turn na

nbfaster than gear b:

𝑊𝑏

𝑊𝑎=

1

𝑇𝑎𝑏=𝑛𝑎𝑛𝑏

Wb = rate of revolution of gear attached to robot base

Wa = rate of revolution of gear attached to motor shaft

Wa = 1500 rpm, 𝑛𝑎 = 15 𝑡𝑒𝑒𝑡ℎ, 𝑛𝑏 = 45 teeth

Wb = Wa * 𝑛𝑎/𝑛𝑏 = 1500 * 15/45 = 500 rpm

67

Resolution Ratio

The smallest step feasible by turning the gears:

𝑅𝑒𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛_𝐺𝑒𝑎𝑟_𝑏

𝑅𝑒𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛_𝐺𝑒𝑎𝑟_𝑎=𝑆𝑏

𝑆𝑎=

𝟏

𝑻𝒂𝒃=𝒏𝒂

𝒏𝒃

Sa = 15ο (angular resolution of gear attached to motor shaft)

𝑛𝑎 = 15 𝑡𝑒𝑒𝑡ℎ, 𝑛𝑏 = 45 teeth

Sb = Sa * 𝑛𝑎

𝑛𝑏

= 15ο * 15

45= 5ο

68

Ball-Screw Drives (Page 81 in textbook)

Also known as a Linear Actuator

69

Harmonic Drives (Page 83 in the textbook)

Their main advantages include: high torque capacity,

excellent positioning accuracy and repeatability, compact

design, zero backlash, high single-stage reduction ratios

and high torsion stiffness.

70

Non-Linearity Issues

▪ Backlash – Term describing actuator hesitation and overshoot caused by small gaps between motor gears

▪ Can result in small, but unnecessary, oscillations of the actuator position

▪ Dead Zone – Because the sensitivity of actuators is limited, not every non-zero input will result in action. The Dead Zone is the +/- region above a zero (0) input that will result in no actuator movement.

71

Purpose of Robotic Control Systems

The “brain” performs the following:

• Direct control of a manipulator (forces or displacements)

• Path planning and navigation (mobile robots)

• Compensate for robot’s dynamic properties (inertia,

damping, etc.)

• Avoidance of internal/external obstacles

72

Control Systems

• May use auxiliary computers or embedded

microprocessors.

• Common control methods:✓Open Loop Control

✓Closed Loop Control➢Bang-Bang Control

➢PID Control (Proportional Integral Derivative)

• The control systems have not been standardized

by the industry and are manufacturer specific.

73

Closed Loop Controller

▪ “Two-way” (feedback)

▪ The input is adjusted to drive the output to the intended

value

74

Open Loop Controller

▪ “One-way” signal to the output device

▪ Feedback is not provided to ensure the output matches the

intended

▪ The amount of force that is applied is constant so it’s

affect may be slower or faster than desired (or may vary

depending on the current state of the output environment)

75

Arm Position Sensors (page 88 in textbook &

Appendix E in the ScorBot User Manual)

1. Potentiometer

a) used for course position data

b) Wiper contact causes wear and early

failure

c) Affected by temperature and humidity

d) Requires analog to digital conversion

2. Optical encoder

a) Does not provide positional information

b) Non-contact thus reduced wear

c) Greater resolution and accuracy

d) Larger size than potentiometers

3. Resolver (aka “variable transformer”)

a) Includes position sensing

b) Smaller and more robust

Page 88 in textbook

Appendix E in the ScorBot

User Manual

76

Incremental Encoder Example

• Does not provide positional information

• Non-contact thus reduced wear

• Greater resolution and accuracy

• Larger size than potentiometers

77

Absolute Encoder Example

• Also provides rotational position information.

• The higher the resolution, the higher the cost.

78

Incremental Encoder Resolution

• Encoder Resolution is proportional to the number of holes

on the disk per degree of rotation:

Resolution = Total Pulses / 360deg

• The smallest increment of change is 1 pulse so:

Smallest ∆ ᶿ =1

resolution

What is the resolution of an encoder that has 800 holes (pulses) per disk?

Resolution = 800 / 360 = 2.22 pulses per degree of movement

The smallest incremental change is = 1 / 2.22 = 0.45 degrees/pulse

79

Resolution Clarification (both methods are used)

Resolution - The resolution of a measurement system is the smallest

yet to distinguish difference in values.

For incremental encoders, resolution is defined as counts per turn.

For absolute single-turn encoders, it is positions per turn, expressed

as a multi-bit word. i.e. 720 / 360 = 2 pulses per degree

Encoders usually have from 100 to 6,000 segments per revolution.

This means that these encoders can provide 3.6 deg of resolution for

the encoder with 100 segments and 0.06 deg of resolution for the

encoder with 6,000 segments.

Textbook Page 91: Resolution = Total Pulses / 360 degrees

80



during operation.





4. All software programs and hardware connections shall be

peer reviewed by a second person before being tested.


points).

81

Equipment Safety










82

Equipment Rules








by a second person before being powered.

83

Quality, Budget, and Schedule

“Stay out of Trouble in the First Place”

84

Development Sequence

1. Define the top-level task to be done by the robot

2. Define incremental positions of the arm (positions 1 to x)

3. Define the arm movements (steps 1 to n).

4. Teach the positions to the robot

5. Verify/Review the positions

6. Connect the hardware

7. Write movement software

8. Verify/Review the movement software (peer review)

9. Verify/check the hardware (peer review)

10. Apply power and test

85

Requirement Phase:

1. Top-level description of what must be automated.

Design Phase:

1. Define the task

2. Define the hardware

3. Define the pickup and drop-off points (work positions)

Implement Phase:

1. Implement the hardware

2. Define the incremental arm positions (Teach menu)

3. Program the arm movements (Edit Program menu)

Test Phase:

1. Test (Run Program Menu)

Project Development

86

Schematics that are required for Labs 1 & 2

First lab report is for Lab 2, due in two weeks

You should have FOUR schematics for Lab#1:

1. Standard SPST switch to a relay

2. Relay with Proximity Detector

3. Relay with Photosensor

4. Relay contacts to an LED

You should have ONE schematic for Lab#2:

6. Relay (or normal SPST switch) to a BasicStamp digital

input

Do not copy your partners schematic – you must generate

your own (finished) version based on the draft schematic that

you created during the lab.

87

The End

88

Week #4 – ScorBot Software

Agenda :

1. ScorBot Software commands

2. Chapter 3 – Work Cells Lab Assignment:

Lab Assignment:

Lab_1&2 (combined) due next week.

Lab_3_ScorBot_First_Move.doc (due in two weeks)

89

Basic Stamp I/O Specifications

Input Impedance is 1M ohm

So a 5 Volt input level will result in a:

5V / 1M = 0.000005 = 5uA input current

The input for a logic low must be less than 1.4 Volts

The input for a logic high must be greater than 1.4 Volts

The Basic Stamp CONFIGPIN command allows this to be changed.

The BasicStamp inputs do not contain pull-up or pull-down resisters so

they must be connected to either 0V or +5V if they are being read.

Output current is: Source = 20mA or Sink 25mA per input

Not to exceed: Source = 40mA and Sink = 50mA

90

Two methods of interfacing to a digital input

What size resister is required?

Input impedance is 1M ohm so when the switch is open, the input will

source up to 5uA thru the resister (5V/1M = 5uA).

5uA * 1K = 5mV which is well below the input threshold of 0.5 Volt for a

logic low.

5uA Current flow

91

Digital Input may or may not include internal

pull-up resisters

Gnd

Device which

includes internal

pull-up resisters

Input

THIS WILL WORK IF THE INPUTS

HAVE INTERNAL PULL-UP

RESISTERS.

+5V

Basic Stamp

P8 Input

+5V

THIS WILL NOT WORK

BECAUSE THE BS DOES

NOT HAVE INTERNAL

PULL-UP/DOWN

RESISTERS!

92

Output - Connecting an LED

In this configuration a LOW, or 0V, at P8 will allow current to flow from Vdd (+5V) through the LED and then to ground (thru P8). When P8 is HIGH (+5V), no current will flow and the LED will not light. The LED is Active Low.

Connected on P8

Vdd, NOT Vin.

Low

93

Another configuration that could be used is to have the LED

Active-High. In this configuration the LED will light when the

output is HIGH, or +5V. Current flows from the 5V output on P8

to ground or Vss (0V).

The 220 resistor will limit current flow to

approximately 20mA . The output current

from a BS2 pin should be limited to 20mA

maximum. The maximum current for an

LED is generally 30mA.

Output - Connecting an LED Part 2

High

94

Connecting an Active-Low Switch

Connect a push-button switch to P10 on the Basic Stamp

▪ The push-button is a momentary normally-

open (N.O.) switch. When the button IS NOT

pressed (open), P10 will sense Vdd (5V,

HIGH, 1) because it is pulled-up to Vdd.

▪ When PB1 IS pressed (closed), P10 will sense

Vss (0V, LOW, 0) making it Active-Low.

95

Another configuration that could have been used is shown here. Notice that the position of the switch and resistor have been reversed.

– When the button IS NOT pressed (open), P10 will sense Vss (0V, LOW, 0) because it is pulled-down to Vss.

– When PB1 IS pressed (closed), P10 will sense Vdd(5V, HIGH, 1) making it Active-High.

The BASIC Stamp has uncommitted inputs. That is,

when an I/O pin is not connected and acting as an

input, it cannot be assured to be either HIGH or LOW.

Pull-up and pull-down resistors are needed to commit

the input to the non-active (open) state for switches.

The 1K resistor is used to prevent a short-circuit

between Vdd and Vss when the switch is closed.

Connecting an Active-High Switch

96

Computer-Integrated Manufacturing

Computer-Integrated Manufacturing (CIM) is the manufacturing approach of using computers

to control the entire production process thus allowing individual processes to exchange

information with each other and initiate actions. Through the integration of computers,

manufacturing can be faster and less error-prone, although the main advantage is the ability to

create automated manufacturing processes. Typically CIM relies on closed-loop control

processes, based on real-time input from sensors. It is also known as flexible design and

manufacturing. CIM is much more than simply automating a series of manual operations.

97

3-Step Process to Implement CIM

1. Assessment• Identify weaknesses and strengths

• Include the people and market components (in addition to

hardware and software).

2. Simplification• Eliminate waste so we don’t automate unnecessary tasks

• Continuous improvement should never end!

3. Implementation• Must include performance measurements (before and after)

98

Six Key Measurement Parameters

1. Product Cycle Time

2. Setup Times

• This also reduces Product Cycle Time

3. Inventory cost

4. Quality

• Do the parts meet specifications?

• Reduction of scrap and rework

5. Employee Output (productivity)

6. Continuous Improvement

• Critical but not as definitive to measure

99

Automated Production

1. Flexible Automation• Agile manufacturing – How fast a company can respond to

changes.

• Suited for products with moderate volume and cost and where

the manufacturing process is subject to change.

• FMS – Flexible Manufacturing System

• FMC – Flexible Manufacturing Cell

2. Fixed Automation• Suited for high volume, low cost, well-defined, stable products

• In-line system/cells can usually handle larger parts

• Rotary system/cells usually require less space

100

Fixed Automated Production

Fixed Automation• Suited for high volume, low cost, well-defined, stable products

• In-line system/cells can usually handle larger parts

• Rotary system/cells usually require less space

In-line Rotary

101

Project Development Sequence

1. Define the top-level task to be done by the robot

2. Define incremental positions of the arm (positions 1 to x)

3. Define the arm movements (steps 1 to n)

4. Teach the positions to the robot

5. Verify/Review the positions

6. Connect the hardware

7. Write movement software

8. Verify/Review the movement software (peer review)

9. Verify/check the hardware (peer review)

10. Apply power and test

102

Requirement Phase:

1. Top-level description of what must be automated.

Design Phase:

1. Define the task

2. Define the hardware

3. Define the pickup and drop-off points (work positions)

Implement Phase:

1. Implement the hardware

2. Define the incremental arm positions (Teach menu)

3. Program the arm movements (Edit Program menu)

Test Phase:

1. Test (Run Program Menu)

Project Development

103

Control Systems Programming

• Teach and Repeat Programming: A trained

operator (programmer) typically uses a portable

control device to teach a robot its task manually.

Robot speeds during these programming sessions

are slow.

• Off-Line Programming: The programming is

written off-line, transferred to the robot controller,

and then modified for the exact axis positions.

104

Rule of Thumb – Inform the Operator

The following events should always be identified to the

operator:1) When the robot has completed it’s tasks.

2) When the robot is waiting for a condition change (i.e. arrival of

a part)

3) Fault conditions

These conditions should also be clearly identified in the

software as comment statements.

105

SCORBASE Software Limitations

ScorbaseTM programs are subject to the following

constraints:

• a limit of 16 subroutines can be defined

• a limit of 16 sensor memory stores can be used

• a limit of 16 counters can be used

• a limit of 100 positions can be "taught“ *

• program length is limited to 250 lines *

• relative positions can be defined only in relation to an absolute

position, not in relation to another relative position

* = These limits can be overridden via DOS command line options.

106

Programming Instructions: Basic

Arm Control/Movements

▪ O/C OPEN/CLOSE GRIPPER

▪ GO TO POSITION . . . FAST/SPEED #

▪ WAIT . . . SECONDS

▪ TURN ON/OFF OUTPUT #

▪ REMARK : /PRINT

▪ SET AXIS #. TO ZERO

These are Open-Loop commands

107

Programming Instructions: Loop

& Jump Commands▪ JUMP TO LINE #. . .

▪ SET COUNTER #. . . TO . . .

▪ DECREMENT COUNTER # . . .

▪ IF COUNTER #. . > 0 JUMP TO . . .

▪ SET / RETURN / CALL SUBROUTINE #. .

▪ SET / RETURN / CALL SUBROUTINE #. .

▪ SET MEMORY# . . TO SENSOR

▪ REMARK : /PRINT

These allow for Closed-Loop control:

▪ IF INPUT #. JUMP TO . . .

▪ IF MEMORY #. . < = > MEMORY #. . JUMP .

▪ ON MOTOR #. ERROR, JUMP TO . . . C/S/O

108

X, Y, and Z are referenced to the tool plate.

Pitch, Yaw, and Roll are referenced to the wrist.

The ScorBot Arm – X,Y,Z Coordinates

Y-Axis

-LEFT & +RIGHT

via rotating the base

X-Axis

-IN towards the base

+OUT away from the base

Z-Axis

-DOWN and +UP

109

The ScorBot Arm – Arm Calibration

1. The arm calibration moves the axes at each of the ten speeds, measures the

exact rate of movement, and calculates the true speed ratios between axes.

2. Press “5-Home Menu” and then A-Arm Calibration to perform the calibration.

• The robot first searches for its hard home, and then begins the calibration

process.

• The procedure can take up to 10 minutes.

3. The calibration data is stored in the ZERO file on your disk(ette). When you

copy SCORBASE to another diskette, be sure to copy the ZERO file as well.

110

The ScorBot Arm – Home Position

1. The robot uses micro-switches to establish the position of the arm. The

home position established by the micro-switches is called “Hard Home”.

2. “Soft Home” can be established by the user at a different position but you

should always keep “Soft Home” the same as “Hard Home”.

3. All teach positions are relative to the “Soft Home” position. If you teach

positions and then redefine “Soft Home”, all of your positions will be

changed to the new “Soft Home” reference point.

111

The ScorBot Arm – Home Procedure

1. For safety and for correct operation, always start the arm in the home position.

2. Start the ScorBase software then Power up the controller box.

3. Select “5 Home” from the ScorBase Level 3 Main Menu

4. Watch the robot carefully while executing the next step. If the arm is

moving too close to the base or to another object, hit any key to

immediately stop the homing process.

5. Press “G” to synchronize the robot

The arm will be moved to find each of the movement limit micro-switches and

then will be stopped in the “Hard Home” position.

6. Do not use the “5-Home Menu => Set Present Position as Home” command.

112

Lab Report Improvement Suggestions

1. Describe the signal flow of the hardware.Object = Coil = NC Contacts = LED1 is On

Detected Energized are Open LED2 is Off

2. List the arm positions.

3. Show a diagram of the positions.

4. Flowchart (or pseudo-code) the software for the arm task.

5. Use text to explain how the software works, especially the

new and/or special actions.

6. List potential and actual operational, performance or safety

issues.

7. Describe any constraints or limits of the system.

I.e. system will not operate correctly if the both the source

and destination contain objects.

113

Important note about tonight’s lab…

Note: For lab#3, each student must complete steps 3

to 11 on their own.

It is the only way to learn this material.

114

The End

115

Week #5 – ScorBot Controller I/O

Agenda :

1. ScorBot controller input and outputs.

2. Chapter 4 – End of Arm Tooling

Lab Assignment:

Lab_4_ScorBot_Move_with_Sensors.doc

116

Free Schematic and Flowchart Tools

www.digikey.com/designtools

▪ Scheme-iT – Schematic and Flowchart tool

▪ PartSim – Circuit Simulation

▪ PCBWeb – CAD application for designing &

manufacturing electronics hardware

▪ Quadcept – PCB layout

http://www.digikey.com/designtools

117

End of Arm Tooling – Gripper Types

118

Refresh Slides from Last Week

Review the first six interfacing slides from last

week if necessary.

Questions?

119

1. Eight Inputs

0-1.5V => Input On

2.5-24V => Input Off

Inputs 1 & 2 have panel

switches

2. Outputs 1 to 4

Relay Outputs with NO

and NC contacts

Max of 4A per contact

3. Outputs 5 to 8

Open Collector Outputs

Max of +24V and 0.5A

ScorBot Controller I/O(see Appendix C in the SCORBASE User Manual)

120

1. Figure 1 – The input is an open-collector, NPN type, with a grounded emitter.

2. Figure 2 – The input is an open-collector, PNP type, with emitter connected to +V.

3. Figure 3 – Relay or switch contacts

4. Do NOT connect a voltage to the controller inputs.

Figure 1 Figure 2 Figure 3

ScorBot Controller Inputs(see Appendix C in the SCORBASE User Manual)

Relay

Contacts

Scorbot

121

1. The zener diode protects the input from an overvoltage by limiting the voltage to

+5 Volt.

2. If the input is disconnected then:

Current flows from +5 V thru R2 and the zener. The zener maintains +5 V so the

input voltage is +5 Volt.

Controller Inputs – Circuit Analysis(Input is Open / Not Connected)

Not connected

122

1. The zener diode protects the input from an overvoltage by limiting the voltage to

+5 Volt.

2. If you short the input to ground then:

Current flows from +5 V thru R2 and R1 to ground so:

ScorBot Controller Input

Circuit Analysis (Input is Shorted)

Input

shorted to

ground

𝐼 =5𝑉𝑜𝑙𝑡

𝑅2 + 𝑅1=5𝑉𝑜𝑙𝑡

102𝐾= 49𝑢𝐴

𝑉𝑅1 = 𝐼 ∗ 𝑅1 = 49𝑢𝐴 ∗ 2000 = 0.098 𝑉𝑜𝑙𝑡

0.098V is less than 1.5V so the input will be On.

123

Outputs 1 to 4 have Relay Outputs with NO

and NC contacts:

Outputs 5 to 8 have Open Collector Outputs:

ScorBot Controller Outputs(see Appendix C in the SCORBASE User Manual)

124

ScorBot Controller Outputs(see Appendix C in the SCORBASE User Manual)

OUTPUTS 5 TO 8 DO NOT EXIST ON OUR CONTROLLERS

Think of an open-collector output (Fig 1) as a switch (Fig 2).

However:

a) Do not exceed +24 Volt or 0.5 Amp.

b) Make sure you include a backflow protection diode

across any relay coils.

Fig 1

Fig 2

125

1. Create a schematic that will interface the

proximity sensor to one of the ScorBot inputs.

2. Create a schematic that will interface the

Photoelectric sensor to one of the ScorBot inputs.

3. Can you eliminate the relay by connecting the

sensor directly to the ScorBot?

Extra Lab Credit: How can you configure tonight’s lab

to detect blocks that are two different heights?

Class Assignment

126

There are two software instructions that will allow you to

execute different software commands depending on the

status of an input.

If the specified input is high then jump to the specified line#:

If Input # Jump to ...

Jump to the specified line#:

Jump to Line #...

ScorBot Input Decision Commands

127

The End

Thank You !

128

Week #6 – Conveyor Belt

Agenda :

1. Exam Review

2. ScorBot Conveyor Belt

3. Chapter 5 – Automation Sensors

Electrical connections via schematics

Lab Assignment:

Finish Lab #4 then Start Lab#5

129

Lab Report Due Dates

Lab#2 is due tonight, Oct 3

Lab#3 is due Oct 10

Lab#4 is due Oct 17

Note: Additional explanation about the software and

hardware will be expected.

130

Exam Review

1. Open book exam.

2. Make sure you bring all of your textbook, course notes, labs,

powerpoints, etc.

3. All exam questions can be answered with the help of the class

material.

4. All material up to and including tonight (Week#6) is included.

5. Varied types of questions.

6. One hour objective however I will try to reasonably extend the

time if one hour does not seem to be enough.

7. Look over your class material and be prepared to locate the

answers within your class material.

8. No lecture next week – Exam and then Lab#5.

131

Protective Diode Reminder

The Diode across the relay coil protects the output transistor from

“back EMF” that occurs when the relay coil is de-energized.

132

Sensor Types (see Table 5-3 in Text book)

1. Discrete – Have a single on/off trigger point

a) Limit Switches

b) SPDT

c) DPDT

2. Analog Sensors - measure a range of input conditions such as temperature,

RPM, or pressure which are converted to signals such as 0-5 volts, 0-10

volts or 4-20mA.

3. Non-contact Sensors

a) Proximity

b) Photo-electric

4. Smart Sensors

A smart transducer is an analog or

digital transducer or actuator combined with a processing unit and a

communication interface. Although ScorBot cannot interface directly to

them, they can be connected to the BasicStamp which collects the data

and then provides a true/false command to ScorBot.

133

Smart Sensor Examples

Omega carries many different sensors:

http://www.omega.com/subsection/limit-switches.html

Non-Contact Level Controller for Small Tank

Applications

The LVCN414 Series is a non-contact, ultrasonic level

controller and transmitter that delivers reliable, cost-

effective, high-performance, small-tank fluid handling

control solutions. The LVCN414 targets process, control

and chemical feed applications in small tanks mounted

on skids, tools or machines. It is easily configured

through a USB connection and Windows compatible

software. The LVCN414 allows for real-time/ anytime

measurement, lowering operational costs and increasing

productivity. The LVCN414 is a total small tank level

control and measurement solution.

A-33 RTD

Transmitter

http://www.omega.com/subsection/limit-switches.html

134

Banner SM312D – Diffuse Mode Sensor

▪ Range to 380 mm (15")

▪ Highly repeatable 1 millisecond response

▪ Both sourcing and sinking outputs (150 mA max. each) at

10-30V dc.

bn + bn +

bu 10-30V dc

bu 10-30V dc

– –

wh Load

wh Load

bk Load

bk Load

4-Pin Euro-Style Pin-out

(Cable Connector Shown)

White Wire

Brown Wire Blue Wire

Black Wire

135

Bottle Sensorshttp://www.balluff.com/balluff/MUS/en/products.jsp

http://www.balluff.com/balluff/MUS/en/products.jsp

136

Class Assignment - Sensor Response Time

The Omron-E3F2-R2C4 sensor will be used to count the cans of beer

being filled at a high speed canning plant. Refer to the response time

listed in the datasheet. What is the maximum number of cans that can be

counted on the assembly line in an hour?

137

Conveyor SummarySee Appendix H of the ScorBot User Manual

1. Uses a 12V motor

2. Uses a DB-9 connector for the wiring interface

3. The conveyor does not have a micro-switch to detect position.

Lead Color in D9 Connector Encoder Circuit

Function External Cable Pin # (PC500) Pad #

Power Motor (+ ) red 1

Power Motor (–) green 9

Phototransistor 0 brown 8 4

Phototransistor 1 white 6 3

VLED yellow 3 2

Ground Logic (GND) black 5 1

Microswitch orange 4

Table D-2: Single Axis Wiring with D9 Connector

Note: This table has

not yet been verified as

being accurate.

138

Automatic Conveyor Stop

139

1. Manual control of the conveyor motor:

Create a schematic that will interface the

conveyor belt to one of the ScorBot

outputs.

2. Extra Lab Credit: How can you configure

tonight’s lab to detect blocks that are two

different heights?

3. Note: Make sure that everyone takes

their turn wiring the circuits each night.

Class Assignment

140

Manual Conveyor Stop

141

SET MEMORY #. . TO . . .

This command allows you to enter an arbitrary value and store it in one of 64

memory cells. Each memory cell can have a value of ± 32767.

This command is most valuable for storing the size (in millimeters) of an object.

SET MEMORY# . . TO SENSOR

This command allows you to measure the spread of the gripper fingers in order to

record the size of an object being grasped by the gripper. At run-time SCORBASE

translates this measurement into millimeters, and stores the result in a specified

memory cell (#1 to 64).

SET MEMORY Software CommandScorBot User Manual Page 4-33

142

IF MEMORY #. . < = > MEMORY #. . JUMP . . .

This command is a conditional jump command. It allows you to compare the values

of two memory cells, and to use that comparison to make a real-time decision

regarding the continued course of action.

The comparison operations can be as follows:

IF MEMORY Software CommandScorBot User Manual Page 4-33

Symbol Meaning

= Equal to

< Less than

> Greater than

<= Less than or equal to

>= Greater than or equal to

<> Not equal to

143

ScorBot User Manual

All of the ScorBot software commands are

described in the ScorBot User Manual

starting on page 4-31.

• Paper copies are available for use in the lab.

• A PDF copy can be downloaded from the class website.

144

Optional Assignment

Test the following:

145

The End

Thank You !

146

Week #7 – Exam

Agenda :

1. Exam #1

Lab Assignment:

Lab_5_ScorBot_Conveyor.doc

Please use the time after the exam to:

a) Finish the previous labs.

b) Add optionals.

c) Try something new.

147

Lab Development Process

In order to efficiently share the limited equipment:

1. Design the wiring, create the schematic, and define the

positions.

2. Build the hardware at your desk. Test what you can.

3. Write the software at your desk & save on a floppy disk.

4. Peer review everything.

5. Go to the ScorBot arm for debugging & test.

a) Make connections to the ScorBot controller.

b) Load your program from the floppy disk.

c) Teach the positions that were already defined.

d) Debug and test.

148

The End

Thank You !

149

Week #8 – Work Cells

Agenda :

1. Exam Review

2. Student Survey

3. Chapter 6 – Work-cell support systems

6.3 Vision systems

6.4 Material Handling

6.5 Part Feeding

6.7 Parts Tracking (bar code)

Lab Assignment:

Catch-up or Pixy Video System

150


Lab#2 (BasicStamp Relays) is due tonight, Oct 3

Lab#3 (positions) is due Oct 10

Lab#4 (sensors) is due Oct 24

Lab#5 (conveyor) is due Oct 31

Lab#6 (vision) is due tentatively due Nov 14

Note: Additional explanation about the software and

hardware will be expected.

151

Vision Systems

Vision Tasks:

1. Part Identification (used for tracking)

2. Part Location (acquisition of randomly placed parts)

3. Part Orientation (to allow the part to be correctly gripped)

4. Part Inspection (typically quality control)

Vision Standards (Automated Imaging Association):

AIA A15.08/1 – Analog Camera Connectors

AIA A15.08/2 – Digital Camera Connectors

AIA A15.08/3 – Monochrome Digital Interface Specification

AIA A15.08/4 – RGB Digital Interface Specification

AIA A15.08/5 – Monochrome Analog Interface Specification

AIA A15.08/6 – RGB Analog Interface Specification

These standards are not readily available unless purchased from the AIA.

152

Vision System Components

Serial Data transfer is going to be slower than thru the Data Backplane.

153

Camera Types

• Vidicon tube produces an analog output that is not as linear or as stable as

a CCD device and it can have a 10% error due to image distortion.

• CCD Camera

a) These devices measure the intensity of radiation striking a surface

and converts the intensity to a digital value.

b) Accurate, rugged, and have good linearity (i.e. a scanner)

c) These use a solid-state array of light-sensitive transisters or diodes.

d) Linear Arrays measure a single line

or

Imaging Arrays measure a complete two-dimensional image (and

cost more).

154

Image Measurment

If a 1-inch square produces an image that fills an 8x8 CCD array then the

smallest variation (resolution) that can be detected is 1/8 inch.

However, if a 1-inch square produces an

image that fills an 32x32 CCD array then

the smallest variation (resolution) that can

be detected is 1/32 inch.

Between the two extremes of On and Off are shades of gray which cause the

pixels to be partially on. The number of states between On and Off is called

the gray scale. Current systems have gray scales from 4 to 4096 or higher.

155

Image Analysis & Recognition

Analysis Find the edges of the object

First we create a sharp contrast between the part and the background using

either backlighted surface or a contrasting surface with top lighting.

1. Edge Detection

a) Look for jumps in the gray level using an edge probability value

2. Clustering

a) Uses a discrimination function to find adjacent pixels that have

similar properties.

Recognition Identify the Object

1. Template Matching – compares the video to templates in memory.

2. Statistical Matching – uses an algorithm to identify and evaluate

significant features of the object.

156

Lighting Techniques

• Front Lightinga) Continuous Lighting for still or slow moving objects.

b) Strobed Lighting for fast moving objects.

• Back Lightinga) Greatest contrast of the silhouette but it lacks surface

details.

• Structured Lightinga) A narrow beam of light is used to capture specific

surface details.

• Laser Lighting for 3D scanning

157

Material Inspection

Quality Inspection:

a) Automatic measurements (i.e. ScorBot gripper)

b) Visual Inspection via identification of defects (vision

system)

It’s not enough to “make enough parts for the

day” (i.e. schedule). We must also make

“good” parts (i.e. Quality) which meet or

exceed the specifications. And we must

make them efficiently (i.e. budget).

158

Material Tracking

• Bar Coding>50 different bar coding systems in use

Two most common are:

a) Interleave two of five (numbers only)

b) Code 39 (26 letters, 10 digits, and 7 additional characters)

• Error rate < 1 character in 70M scanned characters

• Most widely used and accepted

• High level of data security

• Radio Frequency TagsUse passive electronic circuits to transmit a code when subjected to

radio frequency energy (i.e. the new chips in credit cards or the “pet

tags” applied under the skin to cats and dogs).

159

Basic Stamp Vision Controller

Left or Right Movement Detector.

What happens if we add two

more light detectors to achieve

high and low indications ?

Or an 8x8 matrix?

Or a 32x32 matrix?

How would we design the

ScorBot software?

160

Pixy Vision Camera

▪ Scans 50 times per second.

▪ Has a USB interface to a external computer (Arduino, Rasberry PI, BasicStamp)

but it also has SPI, I2C, and UART serial interfaces.

▪ Can detect up to 7 color signatures but color codes may be used for more objects

▪ Digital Output (0 or 3.3V) to indicate an object was detected.

▪ Analog Output (0 to +5V) to indicate the position of an object.

▪ Processor: NXP LPC4330, 204 MHz, dual core

▪ Image sensor: Omnivision OV9715, 1/4", 1280x800

▪ Lens field-of-view: 75 degrees horizontal, 47 degrees vertical

▪ Lens type: standard M12 (several different types available)

▪ Power consumption: 140 mA typical

161

Pixy Camera Connections

+5 V

R1=2k

R2=100

k

5.1 V

Pixy Camera

Pin 1

0 to 3.3V

2N2222

330 ohm

ScorBot

Input 0

Pin 6,8,10

Gnd

Simple Object Detection:

162


Position #2

X>160

Y<100

Y-A

xis

of th

e p

latfo

rm

X-Axis of the platform

6" x 6" Loading Platform

Y=200

Position #1

X<160

Y<100

Position #3

X<160

Y>100

Position #4

X>160

Y>100

Pixy Video

Camera

looking down

on the platform

The Pixy Camera will identify a

known object at one of the four

positions and will then tell the

ScorBot Arm which will

“process” the object.

Output#2 Output#3 Position#

0 0 #1

0 1 #2

1 0 #3

1 1 #4

X=0 X=320

Y=0

163


Object location is being identified

Pixy Tracking

Camera

ICS

P C

on

ne

cto

r

ScorBot

Input 1

Arduino

MicroController

Input 1

Input 0

Dig

Ou

t 1

ICS

P C

on

ne

cto

r

USBUSB

Laptop

2N2222

2K ohm

Input 0

2N2222

2K ohm

Dig

Ou

t 0

Input0 Input1 Location# 0 0 0 0 1 1 1 0 2 1 1 3

164

The End

165

Week #9 – Systems Integration

Agenda :

1. Chapter 7 – System Integration

7.4 PLCs

7.5 CNC

7.7 Interfaces

Electrical noise

STUDENT SURVEY!

Lab Assignment:

Lab_6_ScorBot_Vision.doc

166

The Embedded Muse Newsletter

Good Practical hardware and software engineering

information:

The Embedded Muse

The Ganssle Group

Editor: Jack Ganssle,[email protected]

Website:

http://www.ganssle.com/

Subscribe to his newsletter:

http://www.ganssle.com/tem-subunsub.html

167

Industrial Control Design Magazine

Good Practical Manufacturing Control information (control,

design, motion, sensing, etc):

Online Website:

http://www.controldesign.com/

Free Subscriptions:

https://putman.omeda.com/cto/form.do

http://www.controldesign.com/

https://putman.omeda.com/cto/form.do

168

The ScorBot Arm – X,Y,Z Coordinates

Note: It is possible that

the +/- directions are

reversed.

169

What is a PLC?RBT-235, Programmable Logic Controllers

As defined by the National Electrical Manufacturers Association

(NEMA), a Programmable Logic Controller is:

"a digitally operating electronic apparatus which uses a

programmable memory for the internal storage of instructions for

implementing specific functions, such as logic, sequencing, timing,

counting and arithmetic, to control through digital or analog

input/output, various types of machines or process".

In other words, it is a generic, computer controlled device that can be

used to control a process such as required in a a factory

manufacturing environment or a Disney fun ride.

170

What is CNC?

CNC means Computer Numerical Control. This means a computer

converts the design produced by Computer Aided Design software

(CAD), into numbers. The numbers are considered to be the

coordinates of a graph which control the movement of the cutter.

CNC is widely used for lathe, drill press, milling machine, grinding

unit, laser, sheet-metal press working machine, tube bending machine

etc. Highly automated machine tools such as turning center and

machining center which change the cutting tools automatically under

CNC control have been developed. CNC applications also include

welding machines (arc and resistance), coordinate measuring

machine, electronic assembly, tape laying and filament winding

machines for composites etc.

171

Class Design Problem

The CeeMent Manufacturing Company mixes the materials for high strength

concrete and then packages it into 200 lb bags. An Allen-Bradley PLC with

relay outputs is used to control the final packaging. At the very end of this

line, there is a heavy duty conveyor belt which moves the 200 lb bags to

shipping pallets. In order to ensure quality, a special bar-coded bag is

inserted into the system and is then detected by the bar code scanner. Up

to now, the production line is then stopped and a worker must manually

move the bag to the quality test area.

One of the workers submitted a continuous improvement suggestion to use

the extra ScorBot robot which could be commanded by the Allen-Bradley

PLC to move the bag off the line, thus avoiding the manual labor.

You have been asked to design the hardware and functional interface.

The Allen-Bradley PLC has 16 spare relay outputs (N.O. and N.C. contacts)

and four spare digital inputs (two contacts to be shorted).

172

Process Controllers - Basic Stamp Examples

173

Manual Conveyor Stop(possible ground loop problems)

174

Automatic Conveyor Stop(possible ground loop problems)

175

Grounding Problems

Explain how to avoid current loops.

Explain ground isolation.

176

Grounding Problems

177

Improved Grounding

178

Opto-Isolator

Uses an LED and a

photo-transister to

achieve high electrical

isolation between the

input and output

circuits.

Assuming the input and output use two different

grounds, the power surges on the output motor will not

affect the input.

179

Improved Electrical Isolation

180


Position #2

X>160

Y<100

Y-A

xis

of th

e p

latfo

rm

X-Axis of the platform

6" x 6" Loading Platform

Y=200

Position #1

X<160

Y<100

Position #3

X<160

Y>100

Position #4

X>160

Y>100

Pixy Video

Camera

looking down

on the platform

The Pixy Camera will identify a

known object at one of the four

positions and will then tell the

ScorBot Arm which will

“process” the object.

Output#2 Output#3 Position#

0 0 #1

0 1 #2

1 0 #3

1 1 #4

X=0 X=320

Y=0

181


Object location is being identified

Pixy Tracking

Camera

ICS

P C

on

ne

cto

r

ScorBot

Input 1

Arduino

MicroController

Input 1

Input 0

Dig

Ou

t 1

ICS

P C

on

ne

cto

r

USBUSB

Laptop

2N2222

2K ohm

Input 0

2N2222

2K ohm

Dig

Ou

t 0

Input0 Input1 Location# 0 0 0 0 1 1 1 0 2 1 1 3

182

The End

Thank You !

183

Week #10 – Safety

Agenda :

1. Chapter 10 – Safety

2. Peer Review the ScorBot Vision Software

Lab Assignment:

Lab_6_ScorBot_Vision.doc

184

Anheuser Busch Beer Run

Driverless Truck:

http://www.cnbc.com/2016/10/25/driverless-beer-run-bud-makes-shipment-

with-self-driving-truck.html

Manufacturing of aluminum cans:

https://www.youtube.com/watch?v=V4TVDSWuR5E

http://www.cnbc.com/2016/10/25/driverless-beer-run-bud-makes-shipment-with-self-driving-truck.html

https://www.youtube.com/watch?v=hJfhSaMqwbw#t=462.203504

185

Lab_6 Vision Peer/Design Review

1. Refer to Lab_6b_Pixy_Object_Detection.Doc

2. The class will peer review the Arduino software in order to:

a) Understand how it works.

b) Identify and correct any bugs.

c) Identify any operational limitations that it may have.

186

“Experienced” does not mean “careful”

187

Safety – a “must discuss” topic

• Many robot accidents occur during programming,

maintenance, repair, or setup because the worker is likely to

within the robot's working envelope.

• Safety-related publications and guidelines:✓ OSHA's publication 2254 (Revised), "Training Requirements in

OSHA Standards and Training Guidelines”

✓ ANSI/RIA R15.06-1999 (Industrial Robot Safety) Sections 6, 7, 8, & 9

✓ OSHA 29 CFR 1910.333, Selection and Use of Work Practices

✓ OSHA 29 CFR 1910.147, The Control of Hazardous Energy

(Lockout/Tagout)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9910

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9804

188



during operation.





4. All software programs shall be peer reviewed by a second

person before being executed.


points).

189

Equipment Safety










190

Equipment Rules








by a second person before being powered.

191

Work Cell Safety

192

The End

Thank You !

193

Week #11 – Google Driverless Car Video

Agenda :

1. Lab Report Suggestions

2. Google Driverless Car Video

3. Finish Video Lab

Lab Assignment:

Video Lab

194

Week #12 – Project Definition & Design

Agenda :

1. Class Project

Lab Assignment:

Project Definition

Lab_Team_Project.doc

195

Example Table Layout

196

How much is your time worth?

11 participants in the

workplace can cost the

company $14.67 per

minute.

197

Development & Design Steps

198

Project Objectives

199

College versus Industry Projects

1. College labs are not the same as industry projects

• Research and learning orientated.

• Experimentation is encouraged.

• “Learning Curve” is planned for.

• Labs are normally repeated each semester thus results are

predictable.

• Hardware and facilities are normally adequate.

• Delays impact grades but instructors may be forgiving.

2. Industry Projects must meet Quality, Budget, and Schedule objectives

• Goal/objective orientated.

• Completion within budget, schedule & quality is required.

• “Learning Curve” is neither well planned nor understood.

• First-time efforts experience more unplanned negative impacts.

• Access to the hardware is not always easy/adequate.

• Delays cost dollars (which are rarely forgiven).

200

Typical College Lab Execution

1. Students may only be given the lab instructions on the first

night of the lab.

2. Students may not read the lab instructions prior to the first

night of the lab.

3. All parts of the lab may not work. I.e. there will be bugs.

4. Students will experiment to understand the material so

understanding of the purpose and concepts is complete at

the end of the lab.

In industry, we want to define the objectives and

understand the concepts at the beginning of the

project.

204

Week #13 – Coordinates & Repeatability

Agenda :

1. Finish Vision Lab#6b

2. Lab#9 – Coordinates

3. Lab#10 - Repeatability

Lab Assignment:

Lab#9 - Coordinates

Lab#10 - Repeatability

205


Lab#1 (Interface Document) is due Dec 12

Lab#2 (BasicStamp Relays) was due tonight, Oct 3

Lab#3 (positions) was due Oct 10

Lab#4 (sensors) was due Oct 24

Lab#5 (conveyor) was due Oct 31

Lab#6b (vision) is due Dec 5

Lab#9 (Coordinates) is Due Dec 12

Lab#10 (Repeatability) is due Dec 12

206











8) ScorBot output to a relay coil






207

Lab 9 (Coordinates)

Analyze and document the X, Y, Z coordinates for the Scorbot:

1. Which direction/plane is for X, Y, and Z?

2. Which direction is negative and which is positive?

3. Where are the zero coordinates?

4. What are the default coordinates for the Home position?

5. How can you document it so that a different person (not

as skilled) can understand it?

208

Additional Lab Ideas

Use the turntable to move objects to the Scorbot. Add a sensor

to detect position.

Using a conveyor belt, setup the Scorbot for a linear X-axis

object detection via Pixy.

Relative arm movements.

209

The End

210

Week #14 – Project Test & Debug

Agenda :

1. Class Project Documentation

MS-Word Report

Ms-Excel or MathCad used to explain calculations & Data

PowerPoint Explanation

Lab Assignment:

Class Project Test & Debug

Lab_Team_Project.doc

211











8) ScorBot output to a motor relay coil






212

The End

213

Week #15 – Project Documentation &

Course Review

Agenda :

1. Course Review

Lab Assignment:

Class Project Documentation

214

▪ Did you miss anything that was explained in the lab instructions?

▪ Pins were too large.

▪ Laptops were too slow.

▪ Arduino to Scorbot Wires were too short

▪ Arduino code had to be revised.

▪ Pixy video sensitivity was difficult to adjust

▪ Not familiar with the Pixy camera

▪ Common grounding between Arduino, Pixy, and Scorbot

▪ Camera mounting had to be designed and implemented

Video Lab EvaluationWhy did the Video lab require 4+ weeks to complete?

215

Prior-Experience Evaluation

This is a very quick NON-CREDIT pre-test to allow me to

understand your current knowledge and capabilities.

Using the three electronic components, draw a schematic that will

allow the switch to energize the +5volt coil of the relay so that it

turns on the +24volt lamp.

24V Lamp

NO

NC

COMMON+5V

Coil

216

▪ Lab time versus Theory/Lecture time?

▪ Hardware versus Software focus?

▪ Not enough material or too much material?

▪ Text Book?

▪ Lab handouts?

▪ Course was too fast or too slow?

▪ Equipment suitability?

▪ Classroom environment?

▪ Were the Powerpoint Lecture Notes useful?

Course Improvement: Items to consider

217

Brain Storm Session (10 minutes):Document all ideas – all ideas are valid.

Prioritizing (10 minutes):Everyone gets 20 points. Assign your points to the ideas that you feel

will be most beneficial.

I will use the results to guide future improvements.

Course Improvement Workshop What should we change to improve this course?

218

The exam will be both open (part 1) and closed book (part 2).

Bring all of your course notes, lab reports, exams, ect. You will

need whatever you do not bring.

Bring a calculator and pencil. No loaners will be available.

Questions?

Review and Questions

219

The End

Thank You!

220

Week #16 - Final Exam

Exam Time: tbd

All outstanding work is due.

221

It has been fun and exciting this past semester!

Thank-You for taking the class!

Feel free to call me in the future if you think I can help

you in any way.

Thank – You!

Did you register for

Spring Semester

classes?

Documents

Mit-xxx Visual BASIC for Engineeringweb.acd.ccac.edu/~dwolf/files_to_download/RBT-225 - Dan Wolf Dec… · • Manufacturing and process control (PLCs as in RBT-235) Medical Robotics