Hacked Gadgets Forum

July 18, 2009

Rensselaer Polytechnic Formula Hybrid

at 11:20 am. Filed under Complex Hacks, Computer Hacks, Electronic Hacks, Insane Equipment


Rensselaer Polytechnic has entered the Formula Hybrid Competition.Their Rensselaer Formula Hybrid entry is sure to be a strong contender. Best of all to us, they are documenting the build process in a blog for all of us to enjoy. The electronic control seems to be very impressive, I can’t wait to read and see some more details as it progresses. The huge team effort reminds me of the Shell Eco Marathon that we mentioned a few months ago.

"Our car will be controlled by three discrete microcontrollers, one exclusively used to control the battery charging and regulation circutry. This chip will sense the battery reserve voltage, voltage output of the alternator(s), read engine RPM, control the engine throttle, temperature of the battery, and control the safety relay. (There will also be a hardwired (active when high) wire connected to this relay which can be used to shut the car down if the microcontroller circuit fails. We will use a circuit resembling an AND gate MOSFET to keep the relay on (and hence the car battery connected) as long as inputs from the hardwire button in the dashboard and the microcontroller are high.)
A second microcontroller will be dedicated to measuring and regulating the drivetrain. The speed of one of the front wheels needs to be sensed, along with speed of the drivetrain (rear wheels), and temperature of the motor and Curtiss speed controller. This chip will also interface with the 5K-ohm variable resistor in the accelerator pedal, and connect to the speed controller with a digital variable resistor. This device will compare the speed of both drive wheels with the actual static speed of the car, and carry out the critical task of determining slipping during heavy acceleration. The output to the speed controller will be backed off momentarily until traction is gained and speed of each wheel is matched. A smaller task of this device will also serve to sense the brake pedal, and light up the brake light through a logic-level high voltage transistor."