Spring Final Review - University of Colorado Boulder · Thrust Characterization Test •Purpose: To characterize how commands given to Scout relate to the thrust generated •Related

Spring Final Review

Austin Anderson Geoff Inge

Ethan Long

Gavin Montgomery Mark Onorato

Suresh Ratnam

Eddy Scott Tyler Shea

Marcell Smalley

8/24/2014 Aerospace Engineering Sciences - Scout Slide 1

Project Customer: Dr. Eric Frew

Project Advisor: Dr. Ryan Starkey

Background and Purpose

• Autonomous search and rescue multi-copter

• Capable of exploring dangerous urban environments

• Reduce risk to human life

• Map the environment

• Navigating through doorways is a critical capability


Level 1 Objective: Sensing

Measure altitude and relative

position with ±3cm

Side View

Top View

Floor

Doorway Wall

Floor

Doorway

Wall

8/24/2014 Aerospace Engineering Sciences - Scout

Level 2 Objective: Motion

Maintain hover ±6cm

Control position with ±6cm

Level 3 Objective:

Doorway Search and

Maneuver

Search and fly through

doorway

±6cm

1m

1m

Concept of Operations

Slide 3

Multi-copter CAD Design


Breakout Board

FBD/General Design Solution


Ultrasonic Sensor

TOF Camera

APM Autopilot

3.3 V LDO Regulator

UART Ports

2 Port USB HUB

Single Board Comp.

8400 mAh LiPo

Battery

Battery Elimination

Circuit

SD Memory Card RTF X8

Multi-copter

APM Power Module

11.1 V

11.1 V

11.1 V 5.0 V

5.3 V

3.3 V

5.0 V

Regulates Voltage for Sensor Suite

USB 2.0 Lateral Position Data

USB 2.0 Port

USB 2.0 MAVLink Data Packets

PWM Signals to ESC

Regulates Power for APM

Used to Control Mutli-copter

Responsible for Maneuvering and

Navigation

Processes Lateral and Vertical

Positional Data and Formulates

Commands

Used for Lateral Positioning

Used for Vertical Positioning

Relays Power to Components and Hosts Connections

TTL Level Inverted Lateral Position Data

Power

Sensor Suite

Control System

Multi-Copter

Inverter

Minnowboard SBC

Single Board Computer Update • Upon porting TOF camera algorithms to BeagleBone Black, the two devices were

found to be incompatible

• BeagleBone Black has Arm A8 architecture while TOF camera’s Shared Object Files require x86 architecture

• Performed trade study of x86 SBC’s, selected MinnowBoard

SBC BeagleBone

Black MinnowBoard

Architecture Arm A8 x86

Processing Speed

1 GHz 1 GHz

Power Draw 2.5 Watts

(0.5A at 5V) 12.5 Watts (2.5A at 5V)

Mass 38 grams 137 grams

MinnowBoard

Slide 6 Aerospace Engineering Sciences - Scout 8/24/2014

Critical Project Elements

Critical Project Element Consequence of Failure

CPE 1 Capable of ±6cm precision control Without precision control maneuvering will

result in crashes

CPE 2 Relative position measurements

must have ±3cm accuracy If position measurements are inaccurate

control system will be ineffective

CPE 3 10 minute endurance time Failure to meet customer requirements

CPE 4 All components must be within the

multi-copter payload capacity Takeoff capacity critical for flight/mission

success

CPE 5 *(Added

post CDR)

Blade guards must be constructed for protection during testing

Failure to meet customer requirements


Testing Overview and Results


Vicon System Functionality

• Several IR cameras track position of reflected light from markers • Based on camera geometry, position of tracker in space can be found

IR Camera Reflective Markers

• Different Objects can be defined based on the position of their IR markers • The Body frame of each object can be defined by the user • The Vicon global reference frame can also be specified by the user

Vicon Global Reference Frame

Scout Body Frame

• Vicon streams data which can be collected with MATLAB or C++ SDK

• Reports object position and orientation

• Can also get individual marker locations

• 1-250 frames per second • Sub-millimeter accuracy – verifies

± 3cm measurements • 0.5° rotation accuracy


Level 1 Success


Level 1 Success

Relative Position (Vertical) Test

Relative Position (Lateral) Test

Door Detection Test

Sensor Suite Test

Component Testing

Level 1 Objective: Sensing •Design a sensor suite capable of integrating with a multi-copter platform •Sensor Suite shall measure relative position* of targeted objects with an error of no more ± 3cm when located 0-1 m from the targeted object

*from the sensor to a specified point on the doorway

• Purpose: Test ability to differentiate doorway from wall

• Related Requirement: Scout shall be able to detect a doorway

• Test Location: Fleming Indoor Flying Lab

Testing Procedure: 1. Establish connection

between camera and computer

2. Run detection algorithm 3. Verify door can be

detected 4. Repeat steps with

different expected poses

Doorway Detection Test


• Testing Diagram:

Single board computer

Wall

Time of Flight Camera

Doorway

Field of View

USB

Doorway Detection Testing

Actual Test Setup

Test Setup As Seen By VICON

Hough Transform used to find which pixels correspond to doorframe Once frame found 3D data of these pixels was analyzed

Average Error Standard Deviation

Max Error Min Error

Left Frame 4.02 cm 0.1 cm 4.28 cm 3.72 cm

Right Frame 2.72 cm 0.3 cm 3.37 cm 2.26 cm

Doorframe Hough Detection

Cam

era

Pix

el

Camera Pixel

• Purpose of test was to see if the system could identify a doorway or not (yes or no)

• Results o Doorway always detected when present o No false positives

Aerospace Engineering Sciences - Scout 8/24/2014 Slide 12

• Purpose: Testing ability to measure relative lateral position (X & Y) and data validity with VICON

• Related Requirement: Scout shall sense relative position with ± 3cm accuracy • Test Location: Fleming Indoor Flying Lab • Testing Diagram:

Testing Procedure: 1. Establish connection

between camera and computer

2. Run detection algorithm 3. Output relative position data

(distance measurement) 4. Repeat steps with different

expected poses 5. Validate with VICON data

Relative Position (Lateral) Test


Wall

Time of Flight Camera

Doorway

Field of View

VICON markers

Single Board Computer

USB X

Z

Y

Relative Position (Lateral) Results


• Scout was held stationary at a distance of approximately 1 meter from the wall, while the TOF camera and Vicon both took position data

• Error average equal to 1 cm • Errors can be caused by doorway construction/dimension differences • Data concludes ±3 cm accuracy requirement met

• Purpose: Ability to measure relative vertical position (Z) and data validity with VICON

• Related Requirement: Measurement of vertical position must be accurate to within to ±3cm for all capture scenarios

• Test Location: Fleming Indoor Flying Lab • Testing Diagram: Testing Procedure:

1. Establish autopilot, computer, and ultrasonic connections

2. Run measurement algorithm 3. Output relative position data

(distance measurement) 4. Repeat steps with different

expected poses 5. Validate with VICON data

Relative Position (Vertical) Test


Single board computer

Floor

= VICON markers

Ultrasonic Sensor

X

Z

Y

Autopilot - USB, Mavlink

Ultrasonic – UART, 5V TTL


Relative Position (Vertical) Results

• Scout was held stationary at a height of approximately 1 meter while the Ultrasonic sensor and Vicon both took position data

• Error average equal to 0.8 cm • A scalar addition was applied to the data to account for ultrasonic sensor bias • Data concludes ±3 cm accuracy requirement met

Level 2 Success


Level 2 Success

Controlled Maneuver Test

Thrust Profile Test

Controlled Hover Test

Level 2 Objective: Motion •The control system must control the relative position of the platform to ± 6 cm of a commanded position •Scout must maintain controlled hover •Scout must achieve controlled dynamic motion

Mass/Power Breakdown


Component Mass [g]

Mounting 114.2

Time of Flight Camera 140

Ultrasound 4.3

Single Board Computer (Minnowboard)

119

Blade Guards 466

Electronics 66

Total 909.5 Multi-copter 1841

Battery 614

Scout Total 3364.5

Component Current Voltage Power

Single Board Computer (Minnowboard)

2.5A 5V 12.5W

Argos P-100 Time of Flight Camera

1.5A 5V 7.5W

MB1261 Ultrasonic Sensor

100mA 5V 0.5W

APM 2.6 Autopilot 200mA 5V 1W

Multi-copter 40A

(estimate) 11.1V 444W

Total 44.3A 465.5W

1.91 kg Mass:

Power: 50.4 A

44.3 A

1.52 kg

Thrust Characterization Test • Purpose: To characterize how commands given to Scout relate to the

thrust generated

• Related Requirement: Scout shall be capable of controlled maneuvering




Testing Procedure: 1. Calibrate Load Cell 2. Start collecting data into

LabView 3. Increase thrust until load cell

experiences load 4. Every 5 seconds increase

thrust until max thrust is achieved

5. Use the correlation between stick command and force to characterize thrust

Wooden Support Frame

Rope

Load Cell

Thrust Profiling Results

Thrust Force

Pulley Friction

Vehicle Weight

Vehicle Weight

Load Cell

Counter Weight

Vehicle

PWM = 6.89 ∗ Tdesired3 − 129.69 ∗ Tdesired

2 + 901.13 ∗ Tdesired − 569.95

• R/C Controller gives set throttle commands relating to constant PWM signals.

• Load cell gives resulting thrust for a measured PWM signal.

• Allows for PWM signal to be sent through Autopilot from the single board computer.

* Equation implemented as output for onboard processing

Thrust force experienced for various, constant PWM signals

Ultrasonic Accuracy Sensing • Purpose: To ensure that while integrated with the multi-copter, the

ultrasonic sensor could accurately sense to ± 3cm.

• Related Requirement: Sensing shall be accurate to ± 3cm




Floor

Propeller Wash Ultrasonic Wave

Testing Procedure: 1. Record ultrasonic data with propellers off 2. Compare taken data to data from Vicon 3. Get offset from compared data 4. Turn propellers on and ensure that data does not leave ± 3cm accuracy

Vicon Cameras

Controlled Hover Testing • Purpose: To ensure that Scout can hover at ± 6cm of desired position

• Related Requirement: Scout shall be controlled to ± 6cm of commanded position




Testing Procedure: 1. Have manual control on

standby 2. Algorithm should command

for 1m hover 3. Data will be logged to

onboard SD card 4. Validate data with VICON

system Floor

X

Z

Y

1m ±6cm

Controlled Maneuver Testing • Purpose: To ensure that Scout can be controlled to ± 6cm of desired

position

• Related Requirement: Scout shall be controlled to ± 6cm of commanded position




Testing Procedure: 1. Have manual control on

standby 2. Algorithm should command

navigation to 1m away from the wall

3. Scout shall maintain distance for 1 minute

4. Algorithm will command navigation to the center of the doorway

5. Data will be logged and compared to Vicon

Wall

Floor

Z Y

X

±6cm

>1m

1m

0.5m

Level 3 Success


Level 3 Success

Doorway Navigation Test

Level 3 Objective: Doorway Searching & Maneuvering •Search for doorway, measuring 0.9m X 2.0m, through lateral movement along wall •Navigate and maneuver through a doorway upon detection

Doorway Navigation Test

• Purpose: Test Scout’s ability to detect and navigate through a doorway

• Related Requirements: Scout shall be capable of detecting and navigating through a doorway from 1 meter away

• Testing Location: Fleming Indoor Flying Lab


Wall

Floor

Z Y

X

±6cm

Top View

1m

Doorway = 1m

0.5m

Testing Diagram

Procedure: 1. Full system test (with VICON trackers) 2. Ensure connections are made between major

components 3. Arm the system 4. Have manual control on standby 5. Algorithm will command Scout to position itself 1m from

the doorway 6. System will hold position for 1 minute to ensure

sufficient data 7. Scout will then rotate 90° and navigate through doorway

while capturing data 8. Data will be logged to onboard SD card 9. Validate data with VICON system

Systems Engineering


Systems Engineering Approach

• Clarification needed on customer expectations

• System and subsystem understanding

• Success objectives defined

• Prove Verification capabilities

• System functionality understanding

• Critical project element identification

• Necessary components for sensor suite and control system

• Vicon Test facility capabilities

• Multi-copter, positioning sensors, single board computer, and autopilot trade studies

• Major component interface verification (data rates, communication protocols, power input)

• Blade guard and mounting plate fabrication

• Electrical circuit fabrication

• Software relative state data collection/processing, control algorithm development

• TOF camera and ultrasonic output testing

• Autopilot IMU sensor performance characterization

• Autopilot PID gain tuning

• Breakout board voltage distribution testing

• Payload capacity testing

• Doorway Detection Testing

• Propeller interference testing

• Single board computer communication with autopilot/sensor verification

• Single board computer data processing

• Full Scout doorway search and navigation testing

• Controlled hover/maneuver testing

• Relative position testing

• Future project applications: Full building searches, 3D mapping, testing on various multi-copters

• Performed by customer

Scout Project Completion


Systems Engineering Issues

1. Software interface problems BBB unable to communicate with Argos P100 camera

• Led to a late design decision to switch to Minnowboard single board computer

• Called for new mounting and electrical design

• Led to new interface challenges between the Minnowboard and other components (sensors and APM)

2. Blade Guard requirement introduced after CDR Influenced project significantly

• Reduced time available for other parts of project

• Large influence on budget, scheduling, requirements development, testing, multi-copter payload capacity

3. Payload-endurance issue expected a 10 min flight duration with 1.5 kg payload.

• New battery research and testing

• Electrical design and component connection changes


Lessons Learned

1. The design never works perfectly • Off-ramps are critical

• Design has to be flexible, more than one way to complete objectives

• Don’t overlook the little things

2. The more testing the better • More testing means problems can be detected earlier and easier

3. Clear, concise definition of design requirements • Avoid confusion, time delays and inadequate design

4. Design is iterative—re-design is not failure


Project Management


Management Approach


Project Management

Organization • Project Goals

• 3 Levels of Success

• Design requirements • Team member

communication • Master task list

Planning • Schedule • Manpower

• Equal distribution of team strengths and interests

• Facilities • Budget

Monitoring • Weekly Advisor meetings • Weekly team updates • Reallocation of manpower as

necessary • Comparison of planned vs.

actual progress

Lessons Learned • Careful definition of success to ensure meaningful and

achievable project results • Margins are absolutely necessary • Communication is key, don’t assume everyone knows what

you know • Equal involvement from whole team

Project Success • Subsystem Communication • Systems Approach • Iterative Design

On Track?

Yes

No

Project Budget


• Differences: addition of requirements, backup components, repairs, additional testing equipment, design changes

20%

36% 9%

19%

16%

Main Budget Breakdown

Mechanical Electrical

Software/Controls Testing

Margin

Industry Cost


Description Amount Cost

Man Hours* 5,184 hrs $162,000

Overhead 200% $324,000

Sr. Projects Budget $5000 $5,000

Multi-copter Budget $3000 $3,000

TOTAL $494,000

• Calculated using average of 18 hours per week per person • Cost then based on hourly wage derived from average entry level

salary for B.S. in AES ($65K)

1Hee Jin Sohn; Byung-Kook Kim, "A Robust Localization Algorithm for Mobile Robots with Laser Range Finders," Robotics and Automation, 2005. ICRA 2005. Proceedings of the 2005 IEEE International Conference on Robotics , pp.3545,3550, 18-22 April 2005

2Steux, B.; El Hamzaoui, O., "tinySLAM: A SLAM algorithm in less than 200 lines C-language program," Control Automation Robotics & Vision (ICARCV), 2010 11th International Conference on , pp.1975,1979, 7-10 Dec. 2010

3Bachrach, A.; de Winter, A.; Ruijie He; Hemann, G.; Prentice, S.; Roy, N., "RANGE - robust autonomous navigation in GPS-denied environments," Robotics and Automation (ICRA), 2010 IEEE International Conference on , pp.1096,1097, 3-7 May 2010

4“Laser Scanners, TiM3xx / TiM31x / Indoor / Short Range” , SICK Sensor Intelligence., https://www.mysick.com/ecat.aspx?go=FinderSearch&Cat=Gus&At=Fa&Cult=English&FamilyID=344&Category=Produktfinder&Selections=53789 [Cited 10 October 2013]

5“Mid range distance sensors, Dx35 / DS35 / IO-Link” , SICK Sensor Intelligence., https://www.mysick.com/ecat.aspx?go=FinderSearch&Cat=Gus&At=Fa&Cult=English&FamilyID=402&Category=Produktfinder&Selections=75114 [Cited 10 October 2013]

6“AT: Samsung Li-Ion 18650 Cylindrical 7.4V 2800mAh Flat Top Rechargeable Battery w/ PCM Protection” , All-Battery.com, Total Power Solutions, http://www.all-battery.com/SamsungLi-Ion18650_7.4V_2800mAhwithPCM-31444.aspx [Cited 13 October 2013]

7“BeagleBone Black” , beagleboard.org, http://beagleboard.org/Products/BeagleBone%20Black [Cited 7 October 2013]

8“URG-04LX-UG01 Product Information”, Hokuyo Automatic Co., http://www.hokuyo-aut.jp/02sensor/07scanner/download/products/urg-04lx-ug01/, [September 23, 2013]

9“MB1043 HRLV-MaxSonar®-EZ4? Product”, MaxBotix, http://www.maxbotix.com/Ultrasonic_Sensors/MB1043.htm, [September 27, 2013]

10“3DR RTF X8,” 3D Robotics UAV Technology, http://store.3drobotics.com/products/apm-3dr-x8-rtf, [cited 22 September 2013]

11“APM 2.6 Set (external compass),” 3D Robotics UAV Technology, http://store.3drobotics.com/products/apm-2-6-kit-1, [cited 25 September 2013]

12“Laser Grid GS1,” GhostStop Ghost Hunting Equipment, http://www.ghoststop.com/Laser-Grid-GS1-p/laser-lasergrid-gs1.htm, [cited 10 October 2013]

13“Notch Filters,” Thor Labs, http://www.thorlabs.us/NewGroupPage9.cfm?ObjectGroup_ID=3880&, [cited 10 October 2013]

14“X8 Motor Out Test,” YouTube.com, http://www.youtube.com/watch?v=cdS6Cy5aOvk, [cited 4 October 2013]

References


https://www.mysick.com/ecat.aspx?go=FinderSearch&Cat=Gus&At=Fa&Cult=English&FamilyID=344&Category=Produktfinder&Selections=53789




http://www.all-battery.com/SamsungLi-Ion18650_7.4V_2800mAhwithPCM-31444.aspx







http://beagleboard.org/Products/BeagleBone Black

http://www.hokuyo-aut.jp/02sensor/07scanner/download/products/urg-04lx-ug01/







http://www.maxbotix.com/Ultrasonic_Sensors/MB1043.htm

http://store.3drobotics.com/products/apm-3dr-x8-rtf







http://store.3drobotics.com/products/apm-2-6-kit-1









http://www.ghoststop.com/Laser-Grid-GS1-p/laser-lasergrid-gs1.htm











http://www.thorlabs.us/NewGroupPage9.cfm?ObjectGroup_ID=3880&

http://www.youtube.com/watch?v=cdS6Cy5aOvk

Appendix


Critical Design Requirements

Design Requirements Parent Requirement

DR1 Sensor suite measures relative position while within 1m from the wall at an altitude of 0-2m

CPE 2

DR2 Scout shall be able to detect a doorway CPE 2

DR3 Relative position measurements accurate to within ±3cm CPE 2

DR4 Controlled maneuvering within ±6cm of commanded position

CPE 1

DR5 All components must be within the multi-copter payload capacity CPE 4

DR6 Onboard power supply must meet 10 minute endurance time CPE 3


Prop-Wash Interference Results


Propeller Interference Testing

• Shows propellers do alter data, with a mean of 52.7 cm and a standard deviation of 0.88

• Will not vary the data enough for requirement failure

0 20 40 60 80 100 12052

53

54Propellers Off

Time [1/10 s]

Ultra

so

nic

Da

ta [cm

]

0 50 100 150 20050

52

54

56Propellers On

Time [1/10 s]

Ultra

so

nic

Da

ta [cm

]

Propeller Test Stand

Systems Summary


• Level 1 Objective: Sensing • Design a sensor suite capable of integrating with a multicopter platform

• Sensor Suite shall measure relative position* of targeted objects with an error of no more ± 3cm when located 0-1 m from the targeted object

• Level 2 Objective: Motion • The control system must control the relative position of the platform to ± 6 cm of a

commanded position

• Scout must maintain controlled hover

• Scout must achieve controlled dynamic motion

• Level 3 Objective: Doorway Searching & Maneuvering • Search for doorway, measuring 0.9m X 2.0m, through lateral movement along wall

• Navigate and maneuver through a doorway upon detection

*from the sensor to a specified point on the doorway

Aerospace Engineering Sciences - Scout

Success Objectives

8/24/2014 Slide 39

Payload Capacity Testing

• Testing to ensure new battery could meet 10 min endurance requirement

• Lasted for 12 min 31 seconds with 474 g payload estimation

• Test did not include current draw from sensor suite (minimal compared to multi-copter)

• Further testing will be conducted


Endurance vs. Payload Attachment Test Results

Attached Payload [g] Endurance

Test 1 474 g 12 min 31 sec




Preliminary TOF Camera Test

Testing For • Ability of the time of flight camera to

measure wall from 1 meter away (DR 1) General Procedure 1. Time of Flight Camera placed at a

distance 1m away from test wall/doorway

2. Data was captured by the camera 3. Captured data run through MATLAB

script, pixels and distance measurements plotted.

Results • Camera is capable of producing

measurements within 1m and further.

Time of Flight Camera Range Testing

Ultrasonic Sensor

• Ultrasonic sensor was communicated with using a serial adapter and simulating terminal using RealTerm.

• Data was returned over the TX line of the ultrasonic sensor

• Expected ASCII

letter ‘R,’ followed

by 3 numbers

corresponding to

the distance [cm]


Data Rates

• Scout speed = 0.2 m/s (predefined)

• To be within ±6𝑐𝑚, new position data needs to be acquired, processed and command given in:

𝑡 =0.06

0.2= 0.3𝑠

• 𝑅𝑎𝑡𝑒 =1

0.3= 3.33𝐻𝑧 (At least)

• Camera updates data at 10Hz

• APM can be commanded UP to 100Hz

• With safety factor, command rate is chosen to be 5Hz


Documents

Spring Final Review - University of Colorado Boulder · Thrust Characterization Test •Purpose: To characterize how commands given to Scout relate to the thrust generated •Related