12-03-2012, 03:17 PM
The Robot control using the wireless communication and the serial communication
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Executive Summary
The NASA Robotics Alliance Cadets Program is being designed to be implemented at a
very low start-up cost, and to make this goal obtainable, the program is being developed
using low to no cost components from already developed, well-tested and robust
engineering testbeds.
In this project we are trying to establish both wireless communication between the mobile
Robot and the remote Base Station, and serial communication between the remote Base
Station and the GUI Application. The Base Station requires the serial communication
with the GUI Application and also needs to be hardwired with the radio packet controller,
FRPC2 for wireless control. Our aim is to be able to command and control the Robot
wirelessly by the GUI Application.
Introduction
The NASA Robotics Alliance Cadets Program is a far-reaching, innovative project aimed
at creating a new highly integrated and interactive college undergraduate level curriculum
centered around Robotics and focusing on the content of at least the first two years of
Mechanical Engineering, Electrical Engineering and Computer Science. This project is
being co-led by Mark Leon, NASA AMES Director of Education and David Schneider of
Cornell University and is supported by David Lavery, NASA Program Executive of
Planetary and Solar Exploration. The program is being designed to be implemented at a
very low start-up cost, and to make this goal obtainable, the program is being developed
using low to no cost components from already developed, well-tested and robust
engineering testbeds. The Microcontroller board to be used is the Oregon State University
TekBots platforms, whose base kit is approximately $100.
Project Requirements
Objectives:
• Benchmark the wireless modules.
• Learn the working and functioning of the Tekbot Microcontroller board.
• Interface the Tekbot microcontroller board with a radio packet controller module.
• Interface the Tekbot microcontroller board with a serial port.
• Build a transmitter consisting of the Tekbot microcontroller board interfaced with a
FRPC2 radio packet controller.
• Program the microcontroller so as to wirelessly control the Cadets Robot.
• Program a multithreaded GUI Application so as to serially communicate with the
Base Station.
• Establish the structure of packets for the wireless and serial transmission.
• Solder a tiny26 Microcontroller board
• Develop efficient code along with adequate internal and external documentation.
• Measure the performance and error rate of the packet transmission.
3. Radio Packet Controller Module
The Radiometrix RPC transceiver has been chosen by the RoboCup team as the
communication page link for several previous years. Though it has proven to be an adequate
system, during the competition, many teams used the same RPC unit and were sharing
the same frequencies in their Robots causing interference and drop-outs, especially when
teams were testing their own Robots. Based on the RoboCup team’s trouble, it was
decided to develop a metric to find better alternatives. This entire metric and its results
are mentioned in Section 3.1.
3.1 Design Requirements
The previous system using the RPC is susceptible to interferences caused by the sharing
of same frequencies. Hence we need to find a new system that is not only preventing such
occurrences but also reliable during the uncertain conditions. The system should also
have error-checking capabilities.
