Hello,
Welcome to the Delft University of Technology Racing Team memberspage.
We are a Formula Student Recing team. We compete in the UK and Germany events and we are also present at the Baltic Open event. We are known to build the lightest car in the competition. We were weighed @ 125,5 kg in the UK in 2006.
We are investigating in the VEMS system to use it in the future instead of the MoTeC system.
We are working on a Traction and Launch control system with four wheel speed sensors on the VEMS or with an external system communicating with the VEMS.
Chassis:
Full carbon monoocoque
Engine:
Yamaha wr450 one cylinder.
5 valve cyl head
Power output currently 55 hp with 20 mm restrictor
Current manamgement system: MoTeC M4
36-1 trigger wheel with v/r sensor
1 injector aimed @ the intake valves
Coil on plug ignition coil
5 bar fuel pressure
have a look @ www.dutracing.nl
Best result so far: 2rd overall in the Formula Student UK event. (www.formulastudent.co.uk)
Trigger problem
We have a problem with the trigger wheel. It is a 36-1 trigger wheel that worked fine with MoTeC. The RPM reading is too high (700 instead of 550). We cannot check the timing at the moment.
I do not have the configuration file, because the dyno-pc does not have an internet connection.
I have the following settings in megatune:
Rising edge,
Multitooth,
Filtering disabled,
Advanced filtering disabled,
Special N-1 ENABLED,
Number of teeth on wheel: 35
Trigger tooth: 1
Next trigger tooth: 0 0 is BAD ! Use FF if you don't need a "next trigger" event
Crank min period: 768 us
The timings percentages are as in the help, 75-150 and 150-250 (but these only matter with Advanced filtering enabled)
The constant for RPM calc is 12000
I didn't test the Next trigger tooth settings jet, I currently have the 4 cylinder settings with only one injector and coil connected. This works, except for the problem below (and some tuning, engine doen't run jet.).
I will test it tonight.
Ignition and Fuel Pump cross-talk
When I enable power to the vems, it makes the ignition driver high (no pull-down) for the same time as the fuel-pump powerup. If I change the fuel-pump powerup time, the ignition driver time changes the same way.
This is a problem since we have a coil-on-plug that accepts only a few ms dwell time, or it will die.
It has a high input impedance, but it needs a true 12v/0v signal, so I use a driver and pull-up resistor. It charges on a high signal and ignites on a negative edge.
I tried different ignition outputs, it is currently connected to an injector driver.
I tried different fuel-pump outputs, but it doesn't help. Even when I disable the fuel-pump output, the problem still exists.
Since I tried so much inputs and outputs, and the problem only exists on outputs that are configured as ignition output, I am quite sure it is a software problem.
I also tried different firmwares, 1.1.18 and 1.0.73
I will upload my config soon.