GPS Sensors

[stevieturbo]

Even the 10Hz LR/Syvecs unit is more than a tad expensive.

the Plex Tuning dash I bought feeds back GPS/Accelerometer info to the Syvecs, not honestly sure what frequency it is though and it's still not a cheap option.

Tim's unit will be by far the best value when it is release given what it includes.

But between driven and undriven wheel speed sensors Kiel, that will cover what you need for minimal cost.

I use that for mine, 1 undriven and 2 driven sensors and that covers boost by gear and any other speed related options including traction control.

You could just go for 1 of each if you really wanted. The normal speedo takeoff on your gearbox would probably cover the driven wheel speed aspect as opposed to actual sensors at the wheels or shafts.

[Benkku]

Nowadays, one can build a suitable 50 Hz GPS receiver under 100 USD.
https://www.tindie.com/products/smoking ... out-board/
or 50 Hz GPS, with RTK for around 200 USD.
http://navspark.mybigcommerce.com/ns-hp ... -receiver/
http://navsparkcommunity.ning.com/blog

[stevieturbo]

Nowadays, one can build a suitable 50 Hz GPS receiver under 100 USD.
https://www.tindie.com/products/smoking ... out-board/
or 50 Hz GPS, with RTK for around 200 USD.
http://navspark.mybigcommerce.com/ns-hp ... -receiver/
http://navsparkcommunity.ning.com/blog

And will it transmit the data to the ecu via CAN ?

[RICE RACING]

The LR GPS unit just like my Race Logic VB3i, will have IMU integration allowing 'dead rekoning' which eliminates false GPS speed traces in interference laden environments, this combined with high quality connections prob goes towards justifying the prices, if I put up how much my VBOX professional equipment costs most here would have a heart attack

[Benkku]

And will it transmit the data to the ecu via CAN ?

It depends... Transmitting over CAN is not the problem (adds 20-50 USD) - to ECU memory it certainly might be, as;
- there is no 'standard' nor open communication protocol/documented methology to input this kind of 'external' rather generic data
- ECU memories might be limited

Overall, in terms of data usage etc. Engine/powertrain ECU memory - imho - is not the proper/correct place to store 'track' data.

[stevieturbo]

And will it transmit the data to the ecu via CAN ?

It depends... Transmitting over CAN is not the problem (adds 20-50 USD) - to ECU memory it certainly might be, as;
- there is no 'standard' nor open communication protocol/documented methology to input this kind of 'external' rather generic data
- ECU memories might be limited

Overall, in terms of data usage etc. Engine/powertrain ECU memory - imho - is not the proper/correct place to store 'track' data.

GPS/Accel data transmitted and recorded via my Plex dash and the Syvecs ecu really takes up negligible memory.

Likewise VBox datalogs of GPS data take up miniscule amounts of memory

Memory is in no way an issue even with a basic S6 with a paltry 1MB of memory.

[kielcivic]

thanks for your input stevie and i think you are right
i have a rear speed sensor running off the 4 wheel studs(hall sensor) and have my front like you said from the gearbox (hall sensor)

i tried to set up gear position but from the logs it always seams to be in the wrong gear.
how do i setup gear postion by wheel speed?
there must be some easy way to do this? as at the min i have no control over boost in gears and rev limit in gears.

how do i setup the rear speed sensor so that it reads true like the fronts?

thanks guys

[stevieturbo]

thanks for your input stevie and i think you are right
i have a rear speed sensor running off the 4 wheel studs(hall sensor) and have my front like you said from the gearbox (hall sensor)

i tried to set up gear position but from the logs it always seams to be in the wrong gear.
how do i setup gear postion by wheel speed?
there must be some easy way to do this? as at the min i have no control over boost in gears and rev limit in gears.

how do i setup the rear speed sensor so that it reads true like the fronts?

thanks guys

It's all in Sensors, Vehicle speed.

Choose the amount of teeth per revolution for each wheel, and then you set wheel diameter ( dry, intermediate, wet as per cal selections ) until correct speed is displayed.

You also need to set sensor types and trigger thresholds etc, but it's all in the Vehicle Speed section. Also select number of teeth per wheel, per speed reading. Min of 1, max of the number of teeth per revolution, or just leave at zero.

Then in vehicle speed select and driven wheel speed select, choose an option.

For me "undriven" ie vehicle speed is my front left wheel as I only have one front sensor.

And Driven wheel speed select I choose average of both rear wheel speed sensors.

If you dont know teeth per reading for front, sort the rears first and then just play with the numbers until it reads correctly. As items are in blue, you need to Device/Program before some changes will take effect. Actually rather annoying in this instance when trying to get speed readings correct.

For gear position ( which needs to reference driven wheel speed ), again Sensors, Gear Position.

Select maximum number of gears

Under Gear Position Sensor select Enable gear position from wheel speed.

Then fill in the suitable drive ratios on the table for Drive Ratios. You can either drive and display this value as a gauge or log it and fill in the table later

After that it should display gears, speeds will all work etc.

[Benkku]

GPS/Accel data transmitted and recorded via my Plex dash and the Syvecs ecu really takes up negligible memory.

Likewise VBox datalogs of GPS data take up miniscule amounts of memory

Memory is in no way an issue even with a basic S6 with a paltry 1MB of memory.

Neglible memory? Quick math.

GGA - Global Positioning System Fix Data, commonly output sentence by GPS receivers, takes around 60 bytes - so in one second at 50 Hz generates 3 kbytes of data. One megabyte memory fills in approximately 340 seconds or under 6 minutes. Add to that, other possibly transmitted/needed GPS sentences (GSA, GSV, RMC and maybe others)* and RTK data, then one megabyte sure appears limited.

* http://www.catb.org/gpsd/NMEA.html

[kielcivic]

thanks for all that info stevie thats help alot