Start
• Mavric-II
Board
• Sensor
Board
• LCD
Panel Board •
Sensor & Thermocouples •
Two-Axis
Accelerometer
• Radio
•
Radio
Packet Stategy •
Data
Logging
• Adaptable
System •
Sources and PDF
ADAPTABLE
SYSTEM
We
couldn’t track-test the system before the project’s
deadline; however, we tested the system on the car
with the car’s electrical system, the messaging
function, and the RPM function working. We demonstrated
the system in the lab using 12 VDC to simulate the
car’s electrical system and using various test setups
to exercise the actual sensors. The system worked
perfectly in front of faculty and guests (see Photo
3)!
|
(Click
here to enlarge)
|
Photo
3—The pit crew unit consists of a serial-to-USB
cable and a radio board. The radio board contains
the RS-232 interfacing chip and power regulation.
We found a way to tap the power on the USB cable
so the base unit is self-sufficient. |
Our
wireless telemetry system has many uses. The MAVRIC-II
provides a great CPU daughter card for getting started
with the ATmega128 if you cannot afford a STK500
board, or if you just want a quick solution for
bread boarding. The radios provides a simple and
affordable way to get an FCC-licensed radio quickly
working for the desired range of one track length
(2,000’).
The
flexible software exceeded our expectations. You
can use National Instrument’s LabVIEW, but that
would require a licensed copy and some experience
integrating it. The latter option could be used
with a normal null modem cable to create an automated
lab measurement system.
The
board would be a cost-effective process control
board because of the variety of interfaces and the
power of the processor. You can mix and match the
sensors we described for future versions. However,
more efficient use of the TWI and SPI interfaces
could give you nearly limitless access to various
sensors. The best part is that the programmer can
use the processor’s built-in functions with readily
available chips from companies like Maxim and National
Semiconductor to interface with almost any sensor.
We
intentionally kept the packet protocol simple to
allow for future enhancements, such as additional
sensors and control over the car unit. The spare
serial port can be programmed to interpret and issue
MoTec commands and communicate with a digital engine
interface to create a full authority digital engine
control (FADEC) unit. We raised these issues with
the racing team, but they informed us that a car
without a driver, FADEC control units, and automated
control were forbidden by the rules.
We
were disappointed because we wanted to improve the
car, but an idea was floated about a heads-up display
for cars and aircraft. We can’t wait to see if some
of you can get such a system to work.
