RAC Robotics Soccer

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RAC Robotics Soccer
ROBÓTICA 2005 Coimbra
Omnidirectional Drive Modelling and Robot
Construction

• João Rodrigues
• Sérgio Brandão
• Jorge Lobo
• Rui Rocha
• Jorge Dias

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RAC Robotics Soccer - Main Goals

• Robótica Académica de Coimbra
• Stimulate engineering graduate students for
  robotics and systems integration
• Setup an experimental platform with two RoboCup
  SSL teams of mobile robots
• Participation in national events related with
  robotic soccer
• and in RoboCup competitions

Robots Characteristics - Great Accelerations -
Omnidirectional Model - Limited Autonomy - Little
sensorial capacity and computation power -
Limited Dimensions - ...
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RAC Robotics Soccer

• Real-Time Distributed Control Architecture

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RAC Robotics Soccer

• Robot Hardware
• Via Eden M570 600Mhz CPU
• 4I65 FPGA based PC104-PLUS Anything I/O card
• PC/104 Power Supply V104
• 7I30 Quad 100 Watt H-bridges
• Wireless LAN Mini USB Adapter
• Compact Flash IDE Drive
• DC Micromotors 12v
• ...

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RAC Robotics Soccer

• Part I - Theoretical analysis
• Study of the robots Kinematics
• - Direct Kinematics
• - Inverse Kinematics
• Control Model Study

Omnidirectional Robot Model
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RAC Robotics Soccer

• Part II - Trajectory Control Simulation
• Simulation System Implementation in
  MATLAB/Simulink - The main objective is to
  simulate the real behavior of the robot in order
  to understand its motion.

RAC Motion - Trajectory Control Simulation
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RAC Robotics Soccer

• Part II - Trajectory Control Simulation
• Simulation Results and Analysis

Corrected Trajectory
Real Trajectory
Ideal Trajectory
Set Point 10 10 1 0.05, 10 0 1 0, 20 0 1
-0.1, 20 10 1 0
All Trajectories
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RAC Robotics Soccer

• Part II - Simulation
• Simulation Results and Analysis

Set Point 7 1 1 0.5, 10 3 1 0, 12 6 1
-0.5, 11 9 1 0, 9 10 1 0.5
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RAC Robotics Soccer

• Part III - Calibration
• A calibration procedure was devised to estimate
  unknown skew angles of the wheels

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RAC Robotics Soccer

• Part III - Calibration
• Iterative Calibration Procedure

When the robot movement is parallel to a
wheel axis, i.e. the wheel is not under traction,
we assume that its effect on the trajectory is
minimal and can be neglected 1st Step Inject
trajectory parallel to a W1 wheel axis If robot
bend than correct a2 to correct the
trajectory 2nd Step Inject trajectory parallel
to a W3 wheel axis If robot bend than correct
a1 to correct the trajectory 3rd Step Inject
trajectory parallel to a W2 wheel axis If robot
bend than correct all the parameters a1, a2 and
a3, but a2 in contrary signal to correct the
trajectory.
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RAC Robotics Soccer

• Part IV - Animation
• Development of the Trajectory Control Animation

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RAC Robotics Soccer

• Part V Robots Construction and Development
• Hardware
• - Components Assembly
• Software
• - Linux Platform
• - Development of the Software Aplication.

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RAC Robotics Soccer

• Part V - Robots Construction and Development
• Hardware

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RAC Robotics Soccer

• Part V - Robots Construction and Development
• Software
• - Distribution Gentoo Linux
• -gt Allows to compile the root system
• -gt Customized configuration
• -gt Well documented
• - Development and instalation of a driver to the
  Wireless USB adapter
• - Development of the Loader for the FPGA code
• - Development of testing Aplications.

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RAC Robotics Soccer

• Conclusions
• Developed Work
• Simulator for trajectory control
• Development of prototype
• Development of motion control.
• Further Work
• Validation of simulation results.
• Improvement of the system for trajectory
  generation.
• ...

WEBPAGE http//alumni.deec.uc.pt/brandao/racmoti
on
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RAC Robotics Soccer

• Movie
• RACbot - Robótica Académica de Coimbra
• Prototype I
• 20/04/2005

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RAC Robotics Soccer END

• João Rodrigues
• Sérgio Brandão
• Jorge Lobo
• Rui Rocha
• Jorge Dias