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Yaw channel assignment M150 & GPA

MoTeC M1 Software Tutorial

Discussion and questions related to the course MoTeC M1 Software Tutorial


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Hi,

I am using an M150 with GPA package and have purchased an izze racing IMU.

It's CAN based, and I can assign the acceleration channels to the Vehicle Accelerations in tune, but I can't find anywhere to assign the yaw channels.

Is there a way to feed these values into the ecu for logging? I could use a random unassigned channel I suppose, but that's not ideal.

This is the type of support that the build license is designed for. I have added support in my firmware packages for the IZZE IMU. Contact me if you would like to upgrade to a development/build license, and I could supply a package with this support.

The other option Shane would be to add a dash to your installation and log the IMU channels into that. Of course if you actually want to do anything useful with yaw rate data then a development licence and appropriate firmware is the real answer.

Thanks guys, I saw your response on the motec forum as well after I had posted the question here David - custom package or development license probably wont happen :(

I just replied on the motec forum - but think I have a clear idea on the answer now... the short answer is no haha. Should have probably looked at this before getting the sensor. I finally realise why most setups use the dash for logging, rather than the ecu.

My reply on the motec forum.

...

Unfortunately, there's no custom packaging on the horizon for the car. But I think I am figuring out why most set ups log with the dash, rather than the ecu.... Not much of a problem when I have a dev license.

...

It is possible to bring these in using the Vehicle Acceleration channels, and using the CAN inputs in the Sensor Resource allocation. This however means that all of the other CAN Sensor resources have to be addressed sequential to the 0x4EC message ID that IZZE uses for the base CAN address on these sensors.

^ Yeah, not going to lie - that went right over the top of my head.

Yaw is on 0x4EC and Accel on 0x4ED for the IMU, so I can use the Acceleration channels for yaw (0x4EC), but would this mean I wouldn't be able to use them for the acceleration data?

quick look at tune and dash software to remember how CAN "works"....

The ecu receive can only be set 1 of the 3 CAN buses, with the base ID either set to 0x4EC or whatever. Mine is current set to 0x0500....

I think I can use the C125 as a "translator" to get the IZZE data onto one base ID.... but this still leaves with only 3 acceleration channels on the ECU software, and no where to put the other 3 bits of data.

motec forum

So my question was mainly caused because I was using an older version of the GPA package (v2), the v3 version has the yaw, pitch and roll channels I was looking for.

Stephen give a detailed how to that'll i'll try this weekend on the motec forum thread.

motec forum

So I finally got around to setting up this sensor and it caused a few issues I thought would be worth sharing. I was going to post this in the motec forum as well, but it's been dropping out for some reason.

Firstly a massive shout out to Izze Racing, for being very helpful and patient whilst I stubbled my way through this.

These were the recommendations from the motec forum post, linked in the above post.

Set the ECU Receive CAN ID Base to 0x4EC and ECU Receive Message Type to Sequential

Set the following Sensor Resources in Vehicle XX.

Pitch CAN 0 Offset 0

Roll CAN 0 Offset 2

Yaw CAN 0 Offset 4

Acceleration Lateral CAN 1 Offset 0

Acceleration Longitudinal CAN 1 Offset 2

Acceleration Vertical CAN 1 Offset 4

All Sensor calibrations should be CAN 2DP.1.0.

Voltage Reference is Absolute.

Unfortunately, the above settings didn’t work. My mate and I bought a sensor each and both have the GPA package on an M150, fortunately I also have a C125 dash that I could attempt see if I could get the sensor working on – All connected via the same CAN Bus.

Initially I had the CAN ID wrong for the dash settings, but once I corrected that the sensor was working on the dash. On the ecu I was getting the following error – Invalid CAN Bus

So after some searching around, I found that the CAN receive help listed This value must be a multiple of 16

This led me to excel to try and figure out what was going on with the hexadecimal. Excel has a number of useful functions for converting to and from hex, dec, and binary. I used the HEX2DEC function to create the below table, showing HEX, Decimal and Decimal/16 – we can easily see that unfortunately the default channel for the IMU 4EC, and the default for my sensor (because two sensors were purchased at the same time) 4EE are not divisible by 16.

In the end, I have the IMU working on the ECU, via the dash… So the sensor data is received via the dash on 4EE and 4EF, then sent back to the ECU via 7F0. I need the sensor back to the ECU for logging. The new v2 IMU from Izze Racing allows the user to set the broadcast CAN ID.

I still have two questions though...

1.

If I am understanding CAN correctly, and the way the M1 receives it, if I was to set the base ID to 4E0 – which is divisible by 16. The M150 would still not be able to receive a message on 4EC, because the software allows you to go to a maximum of 4E7 for data – by setting CAN 7 offset x. Am I understanding this correctly?

2.

The Pitch, Roll and Yaw channels do not have a calibration selection, so you can’t select CAN 2DP.1.0 as suggested. You have to set up a table, but it should it be 1 volt = 1 bit, or 1mV = 1bit? I’ll probably set this up tonight and see what I get.