Snowmobile Launch Control

Hello,

We are a student team that modifies snowmobile.

We are currently trying to make a launch/traction control that compare track speed vs gps speed on a snowmobile to have the best launch as possible.

We are using a M150 ECU and a AIM cluster with gps module.

Could you help me on sending the info to the MoTeC and how to setup it so it works?

We need both speed sensors as the vehicle have a CVT transmission, We cannot compare gps speed to RPM.

Don't hesitate if you have any questions.

Thanks in advance,

Mathieu Grenier

Tech Director QUIETS

I would contact David Redszus, Precision AutoResearch, who is a MoTeC (and Aim) dealer involved with racing snowmobiles. Here is his contact info:

Precision AutoResearch

Dr. David Redszus

901 Hillside Drv

Bensenville, IL 60106

Voice: 630-766-4402

Email: PARbrowser@aol.com

Web: www.precisionautoresearch.com

Thank you, will definitely try to contact him.

Hi Matthieu,

GPS Speed is quite laggy compared to actual speeds and is not recommended for use with launch or traction control as it is too inconsistent. As you can see in this image, the GPS speed trace is lagging 0.42 seconds behind the wheel speed traces.

GPS Time lag by Stephen Dean, on Flickr

The M1 can receive GPS over CAN from a MoTeC Dash, but I haven't set one up using data from an Aim System.

Thanks for the reply, what would you recommend to use for a snowmobile launch control? The problem is that my engine rpm is stable around 6900 rpm for all the 500ft acceleration.

My other idea was to make a e-throttle type of launch, but I think that a comparison between the gps and track speed is still the best for this application even tho it has a small lag.

what do you think?

-Mathieu

Salut Mathieu,

Maybe you could use an inertia navigational system (INS) like the Obsidian Motorsports Group one.

https://racespeconline.com/products/obsidian-motorsport-group-ins

http://obsidianeng.com/downloads/

I was about to suggest inertial input, too, as many modern systems have internal "G" inputs.

However, it may not be able to function as a classic "traction control" - my other thought was there are some systems that can use a "ground radar" (operates on the same principle as a pc 'mouse') that is needed when the front wheels are lifted and can give no speed signal - but the snow may be too reflective for it to work accurately.

It may just come down to your driver/rider practicing and getting a feel for what the snowmobile is actually doing - how to place their body to balance grip and lift, throttle transition from off the line to full, etc - in theory max' acc'n is going to be when the skis are just at the point of leaving the ground* and the rider is going to be a significant factor in the mass balance and how the weight is transferred under acc'n - that skill will also be useful for fine tuning any 'traction control' systems you're evaluating.

*In practice, a sensor on the front suspension may be an effective interim measure, the engine giving as much power as practical without excessive lift, and the rider still being critical in positioning them in the right place - not too far farward which will cause excess track slippage or the 'traction control' to kick in, and not too far back that will cause the anti-loop control to cut in.

Of course, different snow conditions will be expected to have different slippage percentages for best grip, but if it was easy everyone would be doing it.

Thanks a lot to both of you!

I think that this season the best will be to make my driver practice as much as possible and I will work on some more technologies in the off season!