Disturbance Correction

Final Design Review

Team 5

February 25, 2003

By: Tyler FermanMatt DiLeoJack Damerji

Laser Deflection System Project Overview

User supplies changing input. Goal is to compensate for measured input

disturbance. Controller angles mirror to performs disturbance

correction. Objectives

Develop accurate controller in order to keep a laser communication link.

Develop controller to correct for all disturbance.

Approach Input

Measure the laser pen pan/tilt angles. Measure the mirror pan/tilt angles.

Controller Determination of desired mirror pan/tilt angles. Develop controller to achieve performance

specifications. Output

Specified target (dot on wall)

Specifications: Positioning

Specifications Cont.Input range of motion: 43o

Mirror: 5’’ dia @ 55g (+ 45g mount) Output Range of motion: 26o Controller Speed: >6rad/s

Overshoot Error: < 1%Target: +-0.4” Encoder Gearing: 1:4 (4X accuracy)

Math Model (Angle Calc.) Pan/Tilt & Mirror Design

Mass & Inertia Calc.

Motor & Gear Selection

Simulation & Controller Design

System Analysis

Input Pan/Tilt Considerations

Order parts

Building Input Pan/Tilt

Input Pan/Tilt &DSP

Input Testing

Build Control Pan/Tilt

DSP Control of Pan/Tilt

Testing and Fine Tuning

Develop Full Interaction

Testing, Tolerance Analysis & Fine Tuning

2/19

2/26

4/1

4/9

Math Model (Angle calc.)

Approach: Direct:

Solve by equating desired reflected unit vector with received reflected unit vector

Solve using parametric equations Indirect:

Solve using Coordinate Transformations Solve using fminsearch & foreword equation

Find foreword Equation (Maple)

Solve For Mirror Angles (Maple)

Create Math Model (MATLAB)

Find foreword Equation (Maple)

Educated Angles Guess (MATLAB)

Iterate Until Guess Converges

Math Model (Angle Calc.) Pan/Tilt & Mirror Design

Mass & Inertia Calc.

Motor & Gear Selection

Simulation & Controller Design

System Analysis

Input Pan/Tilt Considerations

Order parts

Building Input Pan/Tilt

Input Pan/Tilt &DSP

Input Testing

Build Control Pan/Tilt

DSP Control of Pan/Tilt

Testing and Fine Tuning

Develop Full Interaction

Testing, Tolerance Analysis & Fine Tuning

2/19

2/26

4/1

4/9

Motor & Gears Selection

• Center Of Gravity and Inertia were obtained from Solid Work Models

• Simulate a number of motors Examples:

Tested number of GM8000 series Needed more: Torque & Speed Motor Chosen:Pittman GM9234S016Gear Ratio: 4:1

Math Model (Angle Calc.) Pan/Tilt & Mirror Design

Mass & Inertia Calc.

Motor & Gear Selection

Simulation & Controller Design

System Analysis

Input Pan/Tilt Considerations

Order parts

Building Input Pan/Tilt

Input Pan/Tilt &DSP

Input Testing

Build Control Pan/Tilt

DSP Control of Pan/Tilt

Testing and Fine Tuning

Develop Full Interaction

Testing, Tolerance Analysis & Fine Tuning

2/19

2/26

4/1

4/9

Input Considerations

Input trajectory accuracy is critical S1 Optical Shaft Encoder

1024 CPR 3600/1024 = .350 per tick S2 Optical Shaft Encoder

2048 CPR 3600/2048 = .1760 per tick Geared S1 Encoder

1024*4 CPR 3600/4096 = .090 per tick

Error Induced

Output error due to input measurement accuracy 0.10 input

error ~0.0745’’ output error

>> [r,u,p]=find_reflected([0,-2.5,6], [0,.178543307087,-1], [0,0,1]);>> [x,y,z]=vec_plane_int(p,u,[0,0,-1],[0,0,36])x = 0y = 4.9988z = 36>> [r2,u2,p2]=find_reflected([0,-2.5,6], [0,.180344836659,-1], [0,0,1]);>> [x2,y2,z2]=vec_plane_int(p2,u2,[0,0,-1],[0,0,36])x2 = 0y2 = 5.0745z2 = 36

Ordering Parts

Project Budget List of Parts List of Materials Machine shop service

List of Parts

Quantity Price ($)

Total ($)

item source

1 4.25 4.25 5” diameter glass mirror Walmart

1 4.50 4.50 Laser pen Radio Shack

1 97.59 97.59 Pan motor, Pittman GM9234S016 Clickautomation

1 97.59 97.59 Tilt motor, Pittman GM9234S016 Clickautomation

1 25.74 25.74 Pan gear set sdp-si.com/eStore/

1 25.74 25.74 Tilt gear set sdp-si.com/eStore/

1 2.92 2.92 Pan belt sdp-si.com/eStore/

1 2.92 2.92 Tilt belt sdp-si.com/eStore/

1 38.55 38.55 Input Pan/tilt encoder gear set sdp-si.com/eStore/

1 4 4 …mounting hardware sdp-si.com/eStore/

1 38.55 38.55 Output pan/tilt encode gear set sdp-si.com/eStore/

1 4 4 …mounting hardware sdp-si.com/eStore/

1 20.00 20.00 Misc electrical components Trojan electronics

1 2.00 2.00 Mirror mounting hardware Home depo

4 0.89 3.56 6-32 x 2.5” hex head bolts, steel Home depo

371.91 total

List of Materials

Quantity Price Material dimensions item Source

1 0.75 Al 1/8” x 1/2” x 3” Mirror mount Home Depo

1 0.75 Al 3/8” x 6” bar stock Tilt shaft Home Depo

2 1.50 Al 3/8” x 1 1/4” x 2” Tilt spacers RPI machine shop

1 2.50 Al 3/8” x 1 1/4“ x 6” Tilt base RPI machine shop

5.50 total

Machine Shop Service

Quantity rate # hours Total ($)

item source

1 $35 / hr .25 8.75 Mirror mount RPI machine shop

1 $35 / hr .5 17.50 Tilt shaft RPI machine shop

2 $35 / hr .75 26.25 Tilt spacers RPI machine shop

1 $35 / hr 1.0 35 Tilt base RPI machine shop

87.50 total

Total Cost

item Cost ($)

List of parts 371.91

List of materials 5.50

Machine shop service 87.50

total $ 464.91

Project Budget Summary

DSPI/O

Trajectory Calculator

Mirror PositionCalculator

Angle Saturation

Controller

Torque Motor Control

State Estimator

Θin1

Desired States

(Θ1, Θ2, Θ1dot, Θ2dot)

Estimated States (Θ1, Θ2, Θ1dot, Θ2dot)

Voltage for Motors

Torque

State EstimatorΘin2

Θ1

Θ2

Math Model (Angle Calc.) Pan/Tilt & Mirror Design

Mass & Inertia Calc.

Motor & Gear Selection

Simulation & Controller Design

System Analysis

Input Pan/Tilt Considerations

Order parts

Building Input Pan/Tilt

Input Pan/Tilt &DSP

Input Testing

Build Control Pan/Tilt

DSP Control of Pan/Tilt

Testing and Fine Tuning

Develop Full Interaction

Testing, Tolerance Analysis & Fine Tuning

2/19

2/26

4/1

4/9