Duke University Motorsports is a student group that designs and builds open wheel, single seat race cars to compete in the Formula SAE competition sponsored by the Society of Automotive Engineers. The team consists of Duke students from both Pratt and Trinity, in all classes. The purpose of the team is to provide students with a way to gain practical design and manufacturing experience in a fun and challenging setting.

Sunday, January 8, 2012

Electronics Stuff

Some exciting new things with electrics this year: first, we're getting a new ECU (Performance Electronics PE3).  Second, we're doing active aero, and so the controller for that has to be designed.  John (our main electrics guy) and I have been speccing the electrics over break, and we've come up with a number of project we'll be pursuing.
EGT amplifier board, designed in Altium

Because this ECU is much more capable and has the capability for datalogging real-time over wifi, we'll be putting most of the car's sensors through the ECU and pushing them to the DAQ via the CAN bus.  This allows us to have both the DAQ's capabilities and still view the data real-time for diagnostics.

Second, we'll have a fan controller also controlled by the ECU.  The ECU can output a PWM signal, which we'll use to drive the fan via a custom motor controller.  In addition, we'll be putting together a custom thermocouple amplifier for the EGT sensors in order to interface with the ECU.

EGT amplifier case (delrin)

The reason for so many custom electronics is 1) waterproofing, 2) it's actually cheaper for us to do this ourselves, 3) better packaging (commercially, $100 bucks for a 4 channel EGT amplifier and it's quite large - ours is about 1.25"x.75"x.5"), and 4) because we can with minimal time and money investment.

The aero controller is powered by an arduino (mainly because of ease of development/familiarity), and will drive a motor controller with built in feedback (Pololu jrk12v12).  We've put together a schematic for the system already, and all the parts have been ordered so that we can start prototyping.  Hopefully soon we'll have enough tested such that we can get a PCB ordered in the next couple of weeks.

No comments:

Post a Comment