Using racecapture pro mk3 in autox

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cobra440
Posts: 8
Joined: Sat Apr 15, 2017 11:01 pm
Location: California

Using racecapture pro mk3 in autox

Post by cobra440 »

I apologize in advance for my lack of knowledge regarding the system software but am hoping someone on the forum can help me achieve my objective. I am using Racecapture as a GPS source for Solostorm and also to monitor throttle opening, brake pressure, RPM, steering angle, Gsum, and accelerations. That data is transmitted to a Samsung tablet mounted in the car running Solostorm that we review after every run. It works quite well and I am happy with that set up. I also monitor the can bus of a Bosch Mk5 racing ABS for brake pressure for the tablet and to actuate a brake light relay. I wrote a short Lau script routine to turn on my brake lights anytime rear pressure is over 20 psi. The other can bus is used to drive a Shift X2 with the Lau Script for predictive timing modified for Autox. I have it set up to go full red at 1 second behind best predicted time and full blue at 1 second ahead of predicted time. That also works really well and surprisingly the driver loves it. He sees it in his peripheral vision and can see instantly when he makes a mistake by color change and number of LED's lit. Problem areas: We run events that give 10-20 runs a day on the same course. I program the RC by taking it around the course in conjunction with a Nvdia tablet and GPS antenna and go through the routine to name the course ect. I then install the RC in the car and before we run link the Nvidia to RC via WIFI to upload the track. I then have to keep RC on for the rest of the session because I think the track map is stored in volatile memory. The tablet stores track info in one place and RC set up in another file. Am I missing something or is there a way to store one track in non volatile memory within RC? Whenever main power is shut off now we have to reload the track data and we lose fastest lap data. I am looking at adding a small gel cel battery to maintain voltage to RC but thought I would ask here to see if I am missing an obvious programming change that would solve this issue. The RC predictive timing seems to update data with out the tablet once it is loaded so that is not an issue. I could mount that tablet in the car too but would rather not because one more item to charge ect.

Canyonfive
Posts: 69
Joined: Mon Jan 29, 2018 11:20 pm

Re: Using racecapture pro mk3 in autox

Post by Canyonfive »

If you are using solostorm thats all you need for autox. Just send the info to solostorm you want to log like the brake pressure, etc. If he is looking down at the shift x2 he isn't looking ahead enough.

cobra440
Posts: 8
Joined: Sat Apr 15, 2017 11:01 pm
Location: California

Re: Using racecapture pro mk3 in autox

Post by cobra440 »

I want to use predictive timing solostorm is not enough to get all the information needed. My question was related to keeping course memory alive.
"Tell him to look ahead"? Do you think you could do better?

https://youtu.be/dUC7PLCRY3o

https://www.fuelcurve.com/scott-fraser- ... ear-title/

Canyonfive
Posts: 69
Joined: Mon Jan 29, 2018 11:20 pm

Re: Using racecapture pro mk3 in autox

Post by Canyonfive »

HAHAHAHAHAHA. That is funny, yes the exception to the rule. No, Scott doesn't need to do anything differently, nor peters... Maybe I come in third, but really I doubt he needs lights to know when he makes mistakes.

The issue I think you are running into is when you turn it off the RCP creates a new session. The track should still be there. Have you tried updating the bestTime=0 to bestTime=whatever is your fastest from the session throughout the day?

cobra440
Posts: 8
Joined: Sat Apr 15, 2017 11:01 pm
Location: California

Re: Using racecapture pro mk3 in autox

Post by cobra440 »

I will give that a try, thanks for the input. I have a course I use near my house and when I cycled RC off and on it did not recognize my start line. I did not have the tablet in the car though, I will try again. Putting in a desired time was our next step, with the system. I was prepared to remove the lights if Scott did not think they were helpful. He was pissed when they did not work and said it really helped because when he tried slightly different braking points he got immediate feedback. I thought you might get a kick out of the skill level of these guys when you found out they were top level autoxers. Scott does some pretty amazing things with my car and believe me it is very difficult to drive. He never uses more than 56% throttle on these runs and it is still lighting the tires on corner exit. The yellow light below the shiftx display is traction control activated. We pull timing but it still has tons of wheel spin.

Canyonfive
Posts: 69
Joined: Mon Jan 29, 2018 11:20 pm

Re: Using racecapture pro mk3 in autox

Post by Canyonfive »

Well. Yeah. I have a few national championships myself, but those guys are considered above top level.

With the motorsports abs system you have, you have individual wheels speeds. Why not implement some sort of traction control? Those courses look very much pin turn, drag, pin turn.

Same with launch control for the start? With 10-20 runs it would be possible to dial it in to get consistent starts and 60' times.

Also maybe use a different throttle configuration to give say 60% throttle for 100% of the travel?

cobra440
Posts: 8
Joined: Sat Apr 15, 2017 11:01 pm
Location: California

Re: Using racecapture pro mk3 in autox

Post by cobra440 »

The car has FAST EFI 2.0 with traction control that monitors driveshaft rpm delta per .1 second. We program how much slip is acceptable and then pull timing (up to 25 degrees) to try to control it. The engine makes 450lb/ft at 3000 rpm, 562 lb/ft at 7500, and 460 lb/ft at 9000 rpm, HP is 820 at 8200. Rear end ratio is 4.88 so the available torque can easily overcome any 200 tw tire at any speed in a 2400 lb car. It is like trying to control a bonfire with a squirt gun. I wish I could activate rear calipers based on slip % but that is beyond my capabilities with the Bosch Mk5. Throttle is mechanical not drive by wire but I designed a throttle cam that opens about 25% for 3" of travel and has 7" of total travel. That slow throttle and the traction control light helps Scott to manage wheel slip. We found that RC sum of G loads really helpful because if you are not at least 1.0 at all times you are not driving hard enough ( not really but that is what I tell Scott). The attached video was shot before I added the Bosch ABS system. The red light in the poor mans head up display indicates wheel slip over 200 DS revs per .1 second. I asked Scott why he braked so early when making that third gear blast and he said the car was so unstable braking that he did not trust it. The Bosch system really keeps it straight under braking and allows more trail braking into a corner. I think you are right about our launch we could better utilize our existing TC system but we are usually so busy adjusting suspension we never get around to it.

https://www.youtube.com/watch?v=UgG0C_6XZS4&t=32s

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