ME 224-Final Project Jim Lovsin Erica Morales Dan Sheehan Josh Widzer

Overview Introduction Introduction Robot Activities Robot Activities Gyroscope Activities Gyroscope Activities Path Programming Path Programming Results Results Future Work Future Work Conclusion Conclusion

Objectives To design and implement an experiment to realize the control of a commercially available robot To design and implement an experiment to realize the control of a commercially available robot To enhance our knowledge of LabView, data acquisition, feedback control, and MEMS sensing To enhance our knowledge of LabView, data acquisition, feedback control, and MEMS sensing

The Goal To create a robot which utilizes gyroscopic feedback control to navigate the predetermined path shown below. To create a robot which utilizes gyroscopic feedback control to navigate the predetermined path shown below ° 36.9° 53.1°

The Equipment A computer with LabVIEW and a data acquisition card A computer with LabVIEW and a data acquisition card A gyroscope sensor (ADXRS150EB) from Analog Devices A gyroscope sensor (ADXRS150EB) from Analog Devices A Boe-Bot Robot Kit ( #28132) A Boe-Bot Robot Kit ( #28132)

Robot Activities Servo Centering Servo Centering Assembly Assembly Basic Paths Basic Paths

Servo Centering Since the servos are not preadjusted in the factory, it is necessary to adjust the servos so that they are stopped when a 1.5 ms pulse is used Since the servos are not preadjusted in the factory, it is necessary to adjust the servos so that they are stopped when a 1.5 ms pulse is used

Assembly The Boe-Bot came unassembled so some assembly was required The Boe-Bot came unassembled so some assembly was required Followed the instructions provided Followed the instructions provided

Basic Paths Forward Forward –Both wheels rotating in the same direction at the same speed Right turn Right turn –Both wheels rotating at the same speed but the left wheel goes forward and the right wheel goes backward Left turn Left turn –Both wheels rotating at the same speed but the right wheel goes forward and the left wheel goes backward

Gyroscope Familiarity Operating Principles Operating Principles –Coriolis Acceleration Fc = 2mv x Ω Fc = 2mv x Ω Capacitive Sensing Capacitive Sensing Self-Test Self-Test Calibration Calibration –First Attempt –Second Attempt Ref: K. Elliot, P. Gupta, K. Reed, and R. Rodriguez “Micromachined Vibrating Gyroscopes: Design and Fabrication” (2002) Northwestern University Mechanical Engineering 381: Introduction to Microelectromechanical Systems Final Project Vibrating MEMS Gyroscope

Self-Test Followed Self-Test Procedure from Chip Data Sheet Followed Self-Test Procedure from Chip Data Sheet Power supply, Multimeter, and Oscilloscope Power supply, Multimeter, and Oscilloscope –RATEOUT Initially 2.5 V –Applied 4.6 V to pin 10. RATEOUT 3.2 V –Applied 4.6 V to pin 11. RATEOUT 1.81 V Satisfactory Self-Test Schematic of ADXRS150EB Ref: Analog Devices, ±1500/s Single Chip Yaw Rate Gyro with Signal Conditioning, ADXRS150EB Data Sheet B.pdf B.pdf

Calibration First Attempt First Attempt –Correlate Angle to Voltage Signal Second Attempt Second Attempt –Correlate Angular Rate to Voltage Signal LabVIEW to acquire and collect the data LabVIEW to acquire and collect the data Excel to analyze the data Excel to analyze the data Block Diagram of LabVIEW Calibration Program

Calibration First Attempt Correlate Angle to Voltage Θi = B0 + B1 Σ Vi Δt Θi = B0 + B1 Σ Vi Δt Where: B0 and B1 are parameters from OLS Experiment: Turned Boe-Bot by hand to a known angle for a given time Angles 90 and 180 (deg) Problems Accurate Positioning and Timing Numerical Integration R 2 = 0.04

Calibration Second Attempt Correlate Angular Rate to Voltage d/dt (Θi) = B0 + B1Vi Where: B0 and B1 are parameters from OLS Experiment: Turned Boe-Bot at a known angular rate for a given time Angular Rate 2.06, 3.05, 1.78 (rad/s) Problems Accurate Positioning and Timing Numerical Integration R 2 = 0.64

Path following programs Basic Stamp Program Basic Stamp Program –Directly creates the PWM signal needed for the servos LabView Program LabView Program –Reads & analyzes readings from gyroscope, controls basic stamp program

Basic Stamp Program ' Robotics with the Boe-Bot - PathProgram.bs2 ' Closed loop path control for the Boe-Bot. ' {$STAMP BS2} ' Stamp directive. ' {$PBASIC 2.5} ' PBASIC directive. DEBUG "Program Running!" ' [Variables] INPUT 0 INPUT 1 INPUT 2 INPUT 3 DOMain: IF ( IN0 = 1 ) THEN Sto IF ( IN0 = 1 ) THEN Sto IF ( IN1 = 1 ) THEN Forward IF ( IN1 = 1 ) THEN Forward IF ( IN2 = 1 ) THEN Right IF ( IN2 = 1 ) THEN Right IF ( IN3 = 1 ) THEN Left IF ( IN3 = 1 ) THEN LeftLOOPENDSto: PULSOUT 13, 750 PULSOUT 13, 750 PULSOUT 12, 750 PULSOUT 12, 750 PAUSE 18 PAUSE 18 GOTO Main GOTO MainForward: IF ( IN2 = 1 ) THEN Forright IF ( IN2 = 1 ) THEN Forright IF ( IN3 = 1 ) THEN Forleft IF ( IN3 = 1 ) THEN Forleft PULSOUT 13, 700 PULSOUT 13, 700 PULSOUT 12, 800 PULSOUT 12, 800 PAUSE 18 PAUSE 18 GOTO Main GOTO Main Main Forward Forleft Forright Left Right Sto Forright: PULSOUT 13, 600 PULSOUT 12, 800 PAUSE 18 GOTO Main Forleft: PULSOUT 13, 700 PULSOUT 12, 950 PAUSE 18 GOTO Main Right: PULSOUT 13, 775 PULSOUT 12, 775 PAUSE 18 GOTO Main Left: PULSOUT 13, 725 PULSOUT 12, 725 PAUSE 18 GOTO Main

LabView Program There are three types of steps: Stopped (0,9) Straight line (1,3,5,7) Turning (2,4,6,8) Nine total steps

LabView Program Front Panel Stop Step

LabView Program Turning Step Step 8: 180 degrees CCW

LabView Program Straight Path Step Forright Zero? No Yes Greater than Zero? No Yes Forward Forleft Read Accumulated Voltage

Path Demonstration

Reliability Testing Performed ten trials to see accuracy of Boe-Bot Performed ten trials to see accuracy of Boe-Bot Measured x and y distance from starting point and endpoint Measured x and y distance from starting point and endpoint Recorded angles robot made using LabVIEW Recorded angles robot made using LabVIEW

Results of Reliability Testing X Error (mm)Y Error (mm)Theta Error (deg) Average Standard Error Desired Angle (degrees) Average Value (degrees Standard Deviation Deviation from Starting Point: Angle Results:

Future Works Create large deviation correction functionality. Create large deviation correction functionality. Closed loop control of distance. Closed loop control of distance. –Use encoders on servo wheels. Use LabVIEW Realtime to improve performance over Windows. Use LabVIEW Realtime to improve performance over Windows. Use wireless g or bluetooth protocol to remove cable from system. Use wireless g or bluetooth protocol to remove cable from system. –Parallax has kits for sale.

Conclusion Successfully completed the task of programming the Boe-Bot to execute a path Successfully completed the task of programming the Boe-Bot to execute a path Enhanced our knowledge of LabVIEW, Basic Stamp, data acquisition, feedback control, and MEMS sensing Enhanced our knowledge of LabVIEW, Basic Stamp, data acquisition, feedback control, and MEMS sensing

Questions?