1. Controlling a Robot with a Neural Network n CS/PY 231 Lab Presentation # 9 n March 30, 2005 n Mount Union College

2. The Problem n To illustrate pattern recognition by a Neural Network, we’ll train a network to recognize when a robot is on a predefined path, and to move it back on the path if it strays to one side n Input signals will come from light sensors n Output signals will control the wheels of the robot

3. LEGO MindStorms Robots n Constructed from LEGO pieces n Yellow “Brick” contains a processor n Programs are loaded into the Brick via an infrared transmitter connected to a conventional computer –write a traditional program –upload to the robot –robot runs the program when RUN button is pushed

4. Programming Language n NQC –Not Quite C –Similar to standard programming languages (collection of instructions) n How to interface with a TLearn network? –Write a program that reads Tlearn-formatted files –I’ve done this for you…. (you’re welcome)

5. Possible Inputs for this problem n Input Signals come from Light Sensors –1 = light, 0 = dark n Case 1: 0 0 –Both sensors on the road n Case 2: 0 1 –Right sensor is off the road n Case 3: 1 0 –Left sensor is off the road n Case 4: 1 1 –Both sensors off the road distributed 4 0.5 0.6 0.4 n Choose “Network/Testing Options”, then –choose a specific weight file from the original project

6. Corresponding outputs for this problem n Two output signals –One for each wheel (1 = move, 0 = stop) n Case 1: –Keep driving straight (both wheels move at same speed) n Case 2: –What should we do (we’re off the road to the right)?

7. Corresponding outputs for this problem n Case 3: –What should we do (we’re off the road to the left)? n Case 4: –What should we do (where’s the road)?

8. Network Configuration n 2 input nodes, 2 output nodes n Rest is up to you to define! n Break into 2 person teams, choose a team name, define the.CF file for your network, then go to lab to train your network n Next time, Robot Testing!!!

9. Controlling a Robot with a Neural Network n CS/PY 231 Lab Presentation # 9 n March 30, 2005 n Mount Union College