Intelligent Traction Control Smart Robot Cole Perrault Fall 2015 ET 493 Wesley Deneke Cris Koutsougeras

Problem Automobiles have adapted distributing power to two or four wheels via differential. Differentials solve this problem by means of a traction control system in order to distribute the power elsewhere to regain traction. Implementing an electronic traction control system onto a robotic platform can serve as a intelligent traction system to control each individual wheel.

Mecanum Wheel Pros Cons Maneuverability 70% Push Force Full Traction Reliability Friction Power Terrain Inclines Weight Sliding

Mecanum Wheels

Holobot

Hardware

DC Motor Gear Ratio: 74.83:1 6V Free-Run 130rpm 6V Free-Run Current 450mA 6V Stall Current 6000mA 6V Stall Torque 130 oz*in 48 CPR gives 3592 Counts per Revolution

Proportional-Integral-Derivative Implementing a closed loop PID system, that can be turned on or off. Will monitor each wheel’s angular velocity and current/torque to determine wheel slippage. Will automatically adjust slipping wheel to normal behavior based on slipping coefficients.

Proportional-Integral-Differential Proportional – Product of gain and measured error. Reduces large part of overall error Integral – Summing error over time to drive the system to smaller error. Reduces final error in a system Derivative – Counteracts the Kp and Ki terms when output changes quickly.

PID System

Methodology 1. Run robot under normal conditions 2. Simulate one wheel slipping under normal conditions 3. Adjust conditions to regain control Experiment 1 - Control; Recording current and angular velocity Experiment 2 - Slipping Condition; Recording current and angular velocity Experiment 3 - Apply more current to slipping wheel to determine percent of slippage.

Soft Controller Using Wireless Xbee Shield to issue movement commands Commands will be described by JSON and XML description language such as OWL or OWL-S CMPS 411 group will give commands over network “Soft Controller” Demonstrate flexibility of the controller command system

Motivation Implement PID system for personal development – learn something Have a platform to be used by future students – teach others Implement small research and development for the stability in systems – perform research Contribution to the school for future interests – school merit Create a platform for soft controller – group development

Current Accomplishments Future Goals Peripherals Research DC Motor Research Voltage Regulation Transfer Function Equations Building the Holobot Coding the Holobot Coding the PID Implementation of PID Testing of PID Integration of Soft Controller

Deliverables PowerPoint Presentation……………………..…………...…Sept. 11 Encoders…………………………………………...…………...Sept. 14 Experiment 1 & 2……………….……………….......…………Sept. 28 Coding/Implementation of PID…………….……………….…..Oct. 1 Experiment 3……………………………….……...…..……..….Oct. 14 PID Analysis……………………………………………..……….Oct. 23 Implementation of Soft Controller…………………...............Nov. 1 Final Analysis……………………………….…………….…… Nov. 20

Holobot Cole Perrault Fall 2015 ET 493 Wesley Deneke Cris Koutsougeras