Autonomous Mobile Plotter

Team Members:

Kim Schuttenberg & Alicia Tyrell

Project Design Review #2

Project Objectives

Accurately move and plot specific shapes on a flat surface, specified by a path.

Position Error & Orientation Correction

Where if displaced the plotter will move to its correct position and orientation up to 1 meter.

Software Specifications

Graphical User Interface Allows the user to enter a path for the

vehicle to follow. Forward xx, Right yy, Left yy.

Allows the user to draw shapes. Squares, Triangles, Polygons, Lines, Rectangle

Software Specification Cont’d

The user can place as many shapes as desired onto the drawing canvas with the following exceptions:

1. The size of the shapes to be drawn cannot exceed the 1m by 1m operational area.

2. All shapes must intersect.[1] [1] Each shape has fixed number of points in which it may

intersect with another shape. 3. Recipe instructions generated cannot exceed 4K

Software Description

Path Determined Nearest Neighbor Method Analysis

1

2

4

5

3 6

7

Software Description Cont’d

Recipe Generation

Recipe Commands OpCode Description

Straight 0xxxxxxx Moves the plotter up to 127 steps forward

Right 110xxxxx Turns the plotter up to 31 steps or 62 right

Left 111xxxxx Turns the plotter up to 31 steps or 62 left

Repeat 101xxxxx Repeat the next instruction 8x +1 (up to 249 times)

Correct[1] 10000000 The plotter will check its position for errors. Relative to the beacons.

Stop 10000100 The plotter will stop.

NOP 00000000 The plotter will do nothing.

[1] See section on Auto-Correct Instruction

Software Description Cont’d Plain Text Assembly

Error Correct (135,45,45) DC.B CorrectDC.W 150DC.B 100DC.B 100

Forward 20cm DC.B FORWARD+53

RIGHT 90 DC.B RIGHT+31DC.B RIGHT+14

Forward 20cm DC.B FORWARD+53

RIGHT 90 DC.B RIGHT+31DC.B RIGHT+14

Forward 20cm DC.B FORWARD+53

RIGHT 90 DC.B RIGHT+31DC.B RIGHT+14

Forward 20cm DC.B FORWARD+53

End of recipe DC.B STOP

Hardware Specification

Operational Area 1m x 1m Flat Surface

Movement Resolution 3.67 mm line segment per step 1.92° per step

Sensors Range: 2 m 38 kHz @ 950 nm ± 50 nm

Emitters Modulated to match sensors

Error Correction Accuracy Within Operational Area

5 cm

5 degree

Beacon 2 Beacon 1

( Paper 1m x 1m )

Beacon 3

10cm

Hardware Description

Device Size 12” x 6” x 9” ( Not including protruding wheels )

Microprocessor 68HC12A4

8 MHz EEPROM

Internal: 4K External: 32K

Static RAM Internal: 1K External: 512K

Hardware Description Cont’d

Stepper Motors Drive Motors

Unipolar Airpax 7.5°/step Sensor Motor

BiPolar:Astrosyn 0.9°/step

Work Division

Kim Schuttenberg Software Low-Level Circuit Assembly

Driver Circuit Board Signal Processing Board Emitter Circuit Board

Vehicle Construction

Alicia Tyrell Software High-Level Circuit Assembly

Modulation Circuit Board

Sensor Circuit Board Vehicle Construction

Work Completed

HardwareDevice Fully Assembled

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Modulation Signal

Signal Processing

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Work Completed/ In Progress

Motion Control

100% Written 90% Tested

Size: 268

Recipe Execution 100% Written 95% Tested

Size: 107

Math Algorithm 100% Written 90% Tested

Size: 499

Measurement 100% Written 40% Tested

Size: 313

Correction 100% Written 0% Tested Size: 253

Software Low-Level

Work Completed/ In Progress

Software High-Level

Main Interface Written: 100% Tested: 96%

496 Lines of Code

Shape GenerationWritten: 100 % Tested: 95%

450 Lines of Code

Path Generation Written: 100 % Tested: 85%

305 Lines of Code

Recipe GenerationWritten: 86 % Tested: 40 %

200 Lines of Code

Java Serial Communication Written: 89 % Tested: 80 %

100 Lines of Code

Power Consumption

Battery Source 4.8 Volts @ 1800 mAh

Logic: 3 hours

Total Measured: 400 mA

Power 1.92 Watts

6.0 Volts @ 3200 mAh Motor ½ hour – 1 hour

Total Calculated: 3 A

Power 18 Watts

Item Quantity Price Amount Stepper Motor, 400 Steps/Revolution 1 $6.75 $6.75Stepper Motor Controller IC 3 $3.25 $9.75Rectifier Diode 1 Amp/ 50 Piv 9 $0.06 $0.54Solderable Perforated Board 2 $2.00 $4.00Tamiya 70145 Narrow Tire Set 1 $7.25 $7.25LTM97AS40 LiteOn AS Infrared Sensor 3 $2.75 $8.25Battery Recharger 1 $29.99 $29.99PK10 Dip Shunts 1 $1.49 $1.49MC68HC12 Eval Board 1 $135.00 $135.0038 kHz IR Reciever Module 1 $3.69 $3.69T0-220 Heat Sink 1 $1.59 $1.59PCB StandOff (4) 3 $1.49 $4.47Center Lug Splicer 1 $5.96 $5.96HLX Flex Screw in Connector 1 $0.43 $0.43Brass M/S Nuts 2 $0.83 $1.66Washers 1 $0.83 $0.83Dual 7.2 9.6 Charger 1 $10.99 $10.999.6 Volts Ni MH RC Batteries 1 $24.99 $24.9914 Pin IC Sockets 5 $0.99 $4.9520 Pin IC Sockets 3 $0.59 $1.779.6 V RC Connector 3 $1.99 $5.97PK2 SubMini PB SW 1 $2.49 $2.49MultiWatt 15 Bridge Driver 2 $3.20 $6.40DIP-16 Quad 1.5A DAR 2 $1.20 $2.40Connector Brkway .100 80 Pos 2 $1.87 $3.74Connector House 2 Pos C-Grid A-Series 15 $0.48 $7.20Connector House 8 Pos C-Grid A-Series 2 $0.85 $1.70Connector House 6 Pos Dual CGrid 1 $1.62 $1.62Emitter IR 950 nm 20 $0.38 $7.60Terminal Crimp Tin Female C-Grid 20 $0.07 $1.41PhotoInterruptor Slot 3.0 MM PCB 3 $0.90 $2.70LCD Module 8x2 Hi Contrast 1 $8.66 $8.66DPDT 3A Switch 1 $3.99 $3.99NiMH AA (Rechargable) 6 $5.00 $30.00

Total Cost $350.23

Cost Analysis

Test Plan

Error Correction: Choose Several points/orientations to

test from. Have correct to known point, measure

error at end.

Recipe Execution: More of a calibration than a test

Straight: Drive a distance, turn, drive a larger distance. Measure distances to find the calibration constant for the strait command

Turning:Drive Straight, turn a large number of times, then drive straight again. The resulting angle can be used to find the rotation calibration constant.

Repeat: Use the straight and turn commands to test.

Potential Problems

Movement Stepper Motor

Questions ?