Subsystem Design Review

P16203

Andre Pelletreau, Kerry Oliviera, Jeremy Willman,

Vincent Stowbunenko, Kai Maslanka

Recap of Last Review

• Functional Decomposition

• Morphological Chart and Concept Generation

• Concept Selection

• Engineering Analysis

• System Architecture

• Feasibility Analysis

• Risk Assessment

• Test Plan

• Next 3 Weeks…

Agenda System Architecture

Requirements Flow Down

Subsystem Interaction

Constant Current and Constant Voltage Loads

Thermal Analysis of Enclosure

Stress Analysis

UML Diagrams

RS-232 Proof of Concept

Stress Analysis for Enclosure

Design of Enclosure and Safety Shield

Air Flow Analysis

Preliminary BOM

Updated Test Plan

Next 7 Weeks…

Subsystem Interaction

Subsystem Engineering Requirements Sub-

System ER

Physical Enclosur

e

Transparent Safety

Enclosure

AC disengaged when lid is

open

AC voltage

not accessibl

e

Able to withstand

UUT failure

1.5’ x 1.5’ x 1’

Quick (dis)connec

t wires

Difficulty to set up / lock in

Time to set up < 1 minute

Loads

Length of test <

5 minutes

Output 1 –

Active Load

Output 2 – Resistive

Load

Data Storag

e

Store Test Data

Feedback

AC disengaged when lid is

open

AC voltage accessibilit

yPass/fail

indicationReason

for failure

UUT on indicatio

n

Test Bench on indicatio

n

Number of test steps

under 5

Cooling

Internal Temperature < 50 ˚C

Processing

Length of test < 5 minutes

Successfully calibrate

UUT

AC disengaged when lid is

open

Tx and Rx data to/from

UUT

AC voltage accessibility

Establish communicatio

n with UUT

Safety

Internal Temperature < 50 ˚C

AC disengaged when lid is

open

Transparent safety

enclosure

Able to withstand

UUT failure

AC voltage accessibilit

y

Constant Voltage Load

Constant Current Load

Stress Analysis for Enclosure Metal

Thermal Analysis

UML Diagrams

UML Diagrams

UML Diagram Cont’d

UML Diagram Cont’d

RS-232 Proof of Concept

Autotransformer Mathematical Proof of Concept

AC Inputs

Two autotransformers were needed to satisfy AC input specifications

The outputs of the transformer will be controlled by a relay

The relay will be controlled by the Arduino Microcontroller

The Hammond Manufacturing Hard Wired 170 Series autotransformer will step down 115 V to 85 V

E100E SOLA HD autotransformer will step from 120 V to 264 V with the added 24 V winding

Feasibility Analysis of Design

Enclosure Material Selection

Enclosure and Safety Shield

Enclosure and Safety Shield

Circuitry and Resistor Layout

Airflow Analysis

Airflow Analysis Cont’d

Preliminary Bill of Materials

Line Item Part Vendor Manufacturer Quantity Price

1 6 ", 200 W Tubular Resistor Farnell Vishay 4 ~40

2 Arduino Mega SparkFun Arduino/ATMEL 1 ~$60

3 21 x 4 (characters) LCD SparkFun N/A 1 $18

4 E075E - Autotransformer (High Line) Newark Sola-HD 1 $51.55

5 168C - Autotransformer (Low Line) Mouser Hammond 1 $77.84

6 25 Ohm Tubular Resistor Newark Multicomp 2 $5.66

Test Plan

Are the physical measurements ≤ the required dimension?

Measure the physical dimensions of the enclosure

Is the length of the test ≤ 5 min? Time the entire test starting from power supply board set

up finishing with the verification of entire unit test.

Is the Internal Temperature ≤ 50 Celsius? Use a thermometer to measure

Are there indications of passing/failure of the test fixture?

Verify that the GUI lists pass/fail after a test in complete

Does the AC disengage when lid is open? Verify power turns off when Safety Shield is opened

Is the AC voltage accessible? Verify that the AC voltage is not accessible and is within

the enclosure.

Is the safety enclosure transparent? Verify that the Safety Shield is transparent and that the

UUT is visible

Is the enclosure able to withstand a failure of the UUT?

Run stress tests and force tests on the base and the safety shield to see how much heat and force each can withstand

Has communication with the UUT been established?

Verify GUI indicates communication has been made

Has data been transmitted and received to/from the UUT?

Verify from GUI that data is being shared and received through the proper completion of the test

Has the UUT been successfully calibrated?

Verify there is an LED indicator that the UUT

Is there reason for failure feedback?

Verify that the GUI states a failure and where in the test it fails

Is there an indication that the UUT is on?

Verify that there is an LED indicator that the UUT is powered on, and a label saying ‘UUT Power On’

Is there an indication that the Test Bench is on?

Verify there is an LED indicator and a label saying ‘Test Bench Power On,’ and verify that the LED is on

Test Plan Cont’d Are the number of test steps less than 5?

Complete set up and verify that the number of steps is less than five per each test (PS Board test, Controller Board Test, and Entire Unit Test)

Is there a quick (dis)connect? Verify the connect and disconnect time is less than 5 seconds for each.

Is the time to set up less than 1 minute? Time the setup of the enclosure

Is the set up difficult? Based on time to set up and the number of steps, verify that those

requirements are met, which will indicate ease of setup.

Is the test data being stored? Connect SD card and USB to computer to see if test data is being stored

Is the budget under $1500? Yes/No

Next 7 Weeks…

• Detailed Design Activities• Updated Test Plan• Finalize detailed CAD• Active Loads• PCB Layout• Final schematics• Bill of Materials• Code Algorithms

• Prototyping Activities• Active Load – Constant

Current• Active Load – Constant

Voltage• RS232 Communications• CNC of Enclosure Materials• Risk Assessment

Questions/Concerns?