For our display we have chosen for e FW Murphy PV750 because it has 3 CAN input possibilities and some analoque inputs as well. This is usefull because we now have a unit that we can program to do the following:
- Receive CAN communications to and from our motor controller (CANopen)
- Receive CAN data from a battery management system (we want this to be J1939)
- Show data on our display and store to USB stick
Why would we want this? Because the Nissan Micra gets an identical setup which will allow everything we learned from our dynamometer setup to be directly applicable to our Nissan Micra. Our Nissan Micra was a automatic normal Nissan Micra but we are converting it to run as an electric vehicle as part of a Project called ZET (Zero Emission Transport) and part of our University Beacon projects in Low Carbon emissions.
In my last post, I mentioned about the problems we had with CANopen and by now things have become a bit clearer and we are sending and receiving PDO messages. yeah. Also, instead of trying to reprogram the PDO's, we were looking at this for a while because it seemed the right way to go, we now use the CAN VCL option in the Curtis controller to build our own Data Objects and have them send all the data we need. The reason we were focussed on using CANopen for this was simple: Don't mix protocols. But the big advantage of CANopen and J1939 is it is standard thus any screen rightly configured would ignore our data (from CAN VCL, which is only necessary for our specific application) but be compatible with the CANopen protocol and thus the RPM data is in the right place and can be displayed on screen without problems, etc. Sometimes realisation is all you need. Or maybe some more sleep.
Now, that is sorted, we will be calibrating the controller soon and then run the test to define the variables for use in my models.
In total our setup now comprises:
- Matlab / Simulink models to test EV control strategies through computer simulation
- A dynamometer setup which will allows us to verify the computed findings as well as test battery behaviour under drive cycle load and off course electric motors.
- A Nissan Micra which has been convertered to an electric vehicle and has been fitted with data logging equipment to validate the findings from computer and dynamometer as well allows for new research in driver training for electric vehicles and human factors research in display layout.
The only thing missing on the Micra for data logging is GPS data. Maybe someone could give me a couple of good pointers on how to achieve that best? Or even better, use the GPS sensor that is already on board for the Satnav. I am open for ideas.
I'll see i'll get some pictures of our setup for on the photo wall or something.