Robotics

THE POWERFULPAPAYASDOOLITTLE INSTITUTES MINI-URBAN CHALLENGE 2014

Stephen XuSticky Note

Team

Robot Design and Programing

Jacob Glueck

Rushad Antia

Stephen Xu

Team

Route Generator Programming

Alex Dano

Mathematician

Paul Neves

Software and Programming Language

Software: Eclipse

Free, open source IDE

Language: Java

Modern object oriented language

Firmware: leJOS

leJOS a JVM for the NXT

Stephen XuSticky NoteRushad

Pathfinder

Generates the shortest path which goes through multiple destinations

A traveling salesman problem

Stephen XuSticky NotePaul

PathfinderAlgorithm: brute force

Start a single robot in the staring parking space

Make it follow the road

Every time a simulated robot reaches an intersection, split it into two robots

The program is threaded to make full use of a multi-core computer


PathfinderEnter the necessary waypoints delimited by spaces: L01A L02A L03A L04A L05A L06A

Total Distance: 392.0

Route: [L00A, I00, I01, L01A, L01B, L01C, L01D, I02, I03, I04, I30, I29, I28, I31, I38, I41, L05A, L05B, L05C, I42, I43, L06A, L06B, L06C, I48, I46, I42, I39, I33, I29, I28, I27, I14, I15, I16, I19, L02A, L02B, L02C, I21, L04A, L04B, L04C, I22, I25, I26, L03A, L03B, L03C, I23, I30, I29, I28, I27, I14, I15, L00A]

Stephen XuSticky NoteAlex

Pathfinder: Challenges

How to actually write the program.

We couldnt run it well on the school computers on one thread.

Stephen XuSticky NoteAlex

Robot Design

Designed in Lego Digital Designer (LDD)

Originally modeled after a shopping cart

Has motile sensors which can see the lines bordering the road and can move to see the lines which divide the parking spots

Stephen XuSticky NoteStephen

LDD DESIGNREAR VIEW


LDD DESIGNFRONT VIEW


Robot Design

Features:

Custom button pusher

Rear wheel drive

4 color sensors


BUTTON PUSHER


Robot Programming: Data and Route Files

We wanted to make it easy to input the route and other data

Solution: store data in a file on the robot

When we run the ION program, if we hold down a button while it is starting up, the program will enter calibration mode

The program will prompt the user to place the sensors over certain colors and will write the data to a file

Stephen XuSticky NoteJacob

DATA INPUT


Robot Programming: Data and Route Files

When the program starts, it reads the route data from a text file

Example file:

DI T90PL3

This moves the robot forwards until an intersection, makes a 90 degree right turn, parks the robot in the third spot on the left and then pulls out of the spot.


Robot Programming: Line Following

Uses four color sensors to determine the exact position of the line


SENSORS: CENTERED


SENSORS: NOT CENTERED


Robot Programming: Line Following

!

PID line following

Proportional to the error

Integral accumulated error

Derivative trend of error


}x

}L

Robot Programming: Turning

Move center of robot to center of next road

Travel distance is modified according to the angle

Total distance is: x + Lcsc()

Turn in place


Robot Programming: Parking

Line follow in the parking lot until the robot gets close to the space

Raise the sensors to look for the parking lines

Back in


Program: Color Identification

RGB values used as Cartesian coordinates

Proximity based on color identification


RGB COLOR CUBE


Robot: ChallengesMany null pointer exceptions

Created method stubs which returned null and never implemented them

Data read-in problem

Using negative array indices which causes data aborts

Calibrating the PID controller and getting proper color values


Documents

Robotics