Twin Telepathy! 2018 Vegas to Reno Time Trials Split Screen

Christian Sourapas

Well-Known Member
Better late than never!

Ride along with my brother and myself at this year's Vegas to Reno Time Trials via split screen. People always ask me who's faster between us two, and this video further vindicates my answer: we're both pretty damn close! After throwing this video together when I should be writing college essays, it's crazy to finally see how similar we drive. Enjoy!


Side note- What is interesting is that the results determined that Brett was 2.7 seconds faster, which makes me question the accuracy of the timing. Does this look like a 2.7 second difference to you guys? I know I shouldn't be crying over spilled milk, but I'm curious if this has happened to anybody else in the past and costed them valuable spots. It did put me 4 spots behind Brett o_O.
 

BrianR

Member
Didn’t Robby post a side by side video showing what appeared to be a similar discrepancy with Andy at a BITD race a few years ago?
Thanks for sharing the videos. It’s awfully fun for us keyboard racers.

Please forgive my tangent-
Are we getting close to having raceday incar footage with telemetry (pedal %, g-force, speed, rpm, gear etc)
Even if it was delayed by 30 minutes I would pay $25 a race.
 

ndvalium

Rescue Director
First off - Watching split screen like that is kinda Bad Ass - I would love to see more of this type videos. It certainly shows driving differences and vehicle set up differences - I looked like Brett is either on or off the gas and you do a lot more feathering of it. But with roughly the same result at the end of a few miles....

On the timing that is very interesting and I am going to forward it to the office to look at. The BITD system is not automated in a key point. That is it uses a human to click the green light when the computer tells them to at your scheduled start time. Human elements in critical timing can have a varied outcomes for sure.

It would be nice if that part of the equation was removed.

Nice work Christian -
 

y2kbaja

Well-Known Member
You mean we're down to hundredths of a second timing using a stop watch?
 

ndvalium

Rescue Director
Wanted to offer a correction as I was mistaken- the go light it automated from the computer. Not human involvement.

Bitd is forwarding it to the timing team for suggestions on what could have happened.


Sent from my iPhone using race-deZert
 

Christian Sourapas

Well-Known Member
Wanted to offer a correction as I was mistaken- the go light it automated from the computer. Not human involvement.

Bitd is forwarding it to the timing team for suggestions on what could have happened.


Sent from my iPhone using race-deZert
Thank you David! I don't want people getting the impression that I'm bashing BITD. We love their series and exclusively race with them for a reason. The purpose of this post is to see what, if anything, can be done to make the timing as accurate as possible. Time trials have now come down to tenths and hundreths of seconds!
 

MAC56

Well-Known Member
Was there any stopping of qualifying runs between your two runs? IE another racer broke or crashed. The way the timing was run in the past start and finish were sychronized for the first car or truck and then reset if a stoppage occurred. Because the sync is by radio human lag on button pushing could happen however it would result in the same deviation for all runs for all entrys until a stoppage then the reset could change the deviation.
 

drofmij

Well-Known Member
Wanted to offer a correction as I was mistaken- the go light it automated from the computer. Not human involvement.

Bitd is forwarding it to the timing team for suggestions on what could have happened.


Sent from my iPhone using race-deZert
So as soon as the light goes green the time starts and turns off at the timing loop at the end of qualifying?
 

jcorsico

Well-Known Member
Based on the video, Brett did not beat you by 2.7 seconds. But that's based on the video. In my personal experience, the videos can be quite bad at maintaining an accurate time. That's why, if you have a data system that links to the video (like in Motec I2), it needs to periodically sync the data to the video. In theory, a single sync should work - but in practice, it does not. With a single sync, the video and the data start to diverge (and pretty quickly). Thus, one of the devices (camera or Motec) is timing wrong (and I would trust Motec more than GoPro).
 

Wendell #527

Well-Known Member
Based on the video, Brett did not beat you by 2.7 seconds. But that's based on the video. In my personal experience, the videos can be quite bad at maintaining an accurate time. That's why, if you have a data system that links to the video (like in Motec I2), it needs to periodically sync the data to the video. In theory, a single sync should work - but in practice, it does not. With a single sync, the video and the data start to diverge (and pretty quickly). Thus, one of the devices (camera or Motec) is timing wrong (and I would trust Motec more than GoPro).
I agree. I’ve had multiple cameras on my car and when I start to make a video I sync them perfectly when the flag drops. When I go to grab a chunk of footage from later in the race, they’re out of sync. The front camera and the back camera show the event a few seconds different from each other. That might be what happened but it will be interesting to see what the experts come up with.
 

ndvalium

Rescue Director
Thank you David! I don't want people getting the impression that I'm bashing BITD. We love their series and exclusively race with them for a reason. The purpose of this post is to see what, if anything, can be done to make the timing as accurate as possible. Time trials have now come down to tenths and hundreths of seconds!
Absolutely - Valid question based on the video presented.

Had dinner with Liz (and much of the BITD staff) tonight and she and I discussed the video a little bit.

On the surface there was only 2 things we could see and both should not result in the big time gap. As you stated, seconds represent starting and finishing positions in every race with such a competitive field of racers.

The obvious can be the age of the transponder. They have a certain amount of battery life. Could they transmit slower if the battery is low - That may be possible. We know the signal strength weakens over time. So did one transponder read from further away than the other? If this is the case at 100 MPH, it still should be milliseconds difference. The other but this is milliseconds also, is placement on the vehicle as some people have them in different places on the truck. Front down tube will have a different time than the back tubes where some put them.

Liz has asked Dave and Art from the Scoring team to review and see if they can come up with anything else that makes sense of this. The video having different timing is something I didnt consider but Im not a video person..

So everyone understands the scoring system that BITD uses for Qualifying and the Race. (I learned more today about it)

The starter has a laptop that is synced with the timing system before the first vehicle leaves. It is then moved to the starter position and plugged into the starter stand. Once everyone has taken their "parade" lap, the scoring team enters a time of start for the first vehicle and the interval that will be used. The starter then calls out the count down from the computer to Donald as he waives the signs at you to start. The computer automatically triggers the green light. If the start has to be interrupted for something that happens on course, they simply enter a new start time. After qualifying they then go back and match the vehicle start times with the finish times omitting any that didn't show or got re-runs for incidents and that gives the qualifying time. Because of the automated portion, it in theory eliminates the need of the scoring system to have a transponder reader at the start of qualifying because the green light is the time, not the vehicle moving past it.

Technology isnt infallible. but it has improved from the days of a person watching a watch and waiving a flag. It can get better. It will get better -

I will let you know if I hear any response Christian - See you all in Laughlin!

Dave
 

jcorsico

Well-Known Member
The starter has a laptop that is synced with the timing system before the first vehicle leaves. It is then moved to the starter position and plugged into the starter stand. Once everyone has taken their "parade" lap, the scoring team enters a time of start for the first vehicle and the interval that will be used. The starter then calls out the count down from the computer to Donald as he waives the signs at you to start. The computer automatically triggers the green light. If the start has to be interrupted for something that happens on course, they simply enter a new start time. After qualifying they then go back and match the vehicle start times with the finish times omitting any that didn't show or got re-runs for incidents and that gives the qualifying time. Because of the automated portion, it in theory eliminates the need of the scoring system to have a transponder reader at the start of qualifying because the green light is the time, not the vehicle moving past it.
This sounds like a very accurate system. Who makes the hardware and software? If it's somebody like MyLaps, then I would think the system is almost bulletproof, and 99% of the discrepancy that we are seeing on the side-by-side videos is because of the GoPro.
 

jcorsico

Well-Known Member
The obvious can be the age of the transponder. They have a certain amount of battery life. Could they transmit slower if the battery is low - That may be possible. We know the signal strength weakens over time. So did one transponder read from further away than the other? If this is the case at 100 MPH, it still should be milliseconds difference. The other but this is milliseconds also, is placement on the vehicle as some people have them in different places on the truck. Front down tube will have a different time than the back tubes where some put them.
Also, assuming you are using a professional system like MyLaps, the battery power in the transponder should have no impact on the the recorded time. The system should either read the transponder or not, with no impact on the recorded time due to battery strength.

Mounting location within the vehicle does matter when you have a 'green light' timing system like BITD is using. If you put the transponder on the front bumper, it has to travel less distance around the track than if you put it on the back bumper. But with the speeds involved, this is a minor discrepency.

If you switched to using the transponder at the start and also at the finish, that would eliminate the error. But that changes the nature of the start, since it's no longer a 'green light' type of start, and instead when the truck actually crosses the start line (less fun!).
 

ndvalium

Rescue Director
Also, assuming you are using a professional system like MyLaps, the battery power in the transponder should have no impact on the the recorded time. The system should either read the transponder or not, with no impact on the recorded time due to battery strength.

Mounting location within the vehicle does matter when you have a 'green light' timing system like BITD is using. If you put the transponder on the front bumper, it has to travel less distance around the track than if you put it on the back bumper. But with the speeds involved, this is a minor discrepency.

If you switched to using the transponder at the start and also at the finish, that would eliminate the error. But that changes the nature of the start, since it's no longer a 'green light' type of start, and instead when the truck actually crosses the start line (less fun!).
I simply know that in the timing trailer, when we do Tech and each vehicle goes through the timing loop, some read from 5 feet away. some have to be directly in front of the system. It is again a millisecond when dealing with high speeds but still a variable.
 

ndvalium

Rescue Director
Can of worms has officially been opened.
naw - no worms - without encoded time line there cant be any firm direction and proof. I dont blame you all to question it but I know in quick conversation, no one can find a reason that would have that big of a descrepency.

As a side note, TUBA!!!! I want to see a 9 screen split shot of qualifying runs. The side by side is great - now I NEED more!!!
 
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