Lap prediction?

Request and discussion on new / to change features
User avatar
gaskleppie
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 31
Joined: Sat Mar 12, 2011 7:10 am

Lap prediction?

Post by gaskleppie »

Ok, lap prediction. This feature is used in other non phone laptimers to predict your laptime.

More and more race classes use "code 60" instead of the safetycar. During this code you are not allowed to drive faster than 60km/h. This results in a certain minimum laptime. With lap prediction we can check what the laptime will be.
You can also use it in classes with a minimum laptime. In the Netherlands we have a Time attack race were the classes are based on a minimum laptime. When you go faster, you are put in a higher class. With lap prediction you can be certain to stay in the right class and still race for the win.

A good prediction will use data from older laps to calculate the laptime during the lap. It must know were you go faster (straights) and were you go slower (corners) to give a steady lap prediction. Its not a easy algorithm but it can be very usefull in some classes!
User avatar
Harry
Site Admin
Site Admin
Posts: 10516
Joined: Sun Sep 12, 2010 10:32 am
Location: Siegum, Germany
Contact:

Re: Lap prediction?

Post by Harry »

LapTimer gives you the gap to a reference lap while driving. E.g. in Timer View. Press Gap to see the time difference for your current position in real time.

Harry
Image Image Image Image
gplracerx
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 836
Joined: Thu May 03, 2012 5:26 am
Location: Kingsport, TN USA

Re: Lap prediction?

Post by gplracerx »

Code 60, otherwise known as a virtual safety car. At VIR in the US, it's Code 35 for 35 MPH or about 56 kph.
User avatar
gaskleppie
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 31
Joined: Sat Mar 12, 2011 7:10 am

Re: Lap prediction?

Post by gaskleppie »

LapTimer gives you the gap to a reference lap while driving. E.g. in Timer View. Press Gap to see the time difference for your current position in real time.
Ok, but then you need to know the reference time and calculate it by yourself while driving...
User avatar
Harry
Site Admin
Site Admin
Posts: 10516
Joined: Sun Sep 12, 2010 10:32 am
Location: Siegum, Germany
Contact:

Lap prediction?

Post by Harry »

Sounds like a workaround calculating a predicted lap time to stay below a certain average speed. This means one needs to know a track configuration specific lap time and a special forecasting for the lap time (it will not be based on a reference lap but on a somehow slowed down reference lap?).

If I understand right, one would like a lap average speed display instead? Instead of configuring this artificial lap time and configuring it, this simple display would be enough? Anything I am missing here?

Harry
Image Image Image Image
User avatar
Harry
Site Admin
Site Admin
Posts: 10516
Joined: Sun Sep 12, 2010 10:32 am
Location: Siegum, Germany
Contact:

Re: Lap prediction?

Post by Harry »

When a code60 is announced and you are in the middle of a lap, how is this handled?
Image Image Image Image
User avatar
gaskleppie
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 31
Joined: Sat Mar 12, 2011 7:10 am

Re: Lap prediction?

Post by gaskleppie »

Code 60 is announced by waved flags on all posts. In the race I competed they took a complete lap to check if you did not went faster, but in theory they also could use the sectors to check if you did not went faster. In our case we could race till the startline and after that keep it steady at 60km/h. But there was a risk that it was visible by eye of the marchalls.
But hey, we were racing a 2cv! ;-)

http://www.stackltd.com/predict.html
http://www.racelogic.co.uk/_downloads/M ... -2010).pdf
gplracerx
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 836
Joined: Thu May 03, 2012 5:26 am
Location: Kingsport, TN USA

Re: Lap prediction?

Post by gplracerx »

Harry wrote:When a code60 is announced and you are in the middle of a lap, how is this handled?
Drivers are supposed to maintain the separation to the car ahead. Course marshals are expected to call in anyone who appears to be gaining significant ground on the car ahead.
User avatar
gaskleppie
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 31
Joined: Sat Mar 12, 2011 7:10 am

Re: Lap prediction?

Post by gaskleppie »

I think lap prediction should be calculated like this:
Put all gps markers from the reference lap in a database with there unique timestamp counted from 0 at the starting line.
With that data you can calculate the laptime by taking that reference timestamps plus or minus the difference in current timestamps while your driving the lap.

For example:
Ref total laptime is 2:00,00

Ref timestamp at gps marker X is 0:45,5
Current timestamp at the same gps point X is 0:44,5
Lap prediction time for that current lap is at gps marker X 1:59,00

Ref timestamp at gps marker Y is 1:20,0
Current timestamp at the same gps point Y is 1:18,0
Lap prediction time for that current lap is at gps marker Y 1:58,00

Ref timestamp at gps marker Z is 1:40,0
Current timestamp at the same gps point Z is 1:42 (made an error on track)
Lap prediction time for that current lap is at gps marker Z 2:02,00

Should be doable ;-)
User avatar
Harry
Site Admin
Site Admin
Posts: 10516
Joined: Sun Sep 12, 2010 10:32 am
Location: Siegum, Germany
Contact:

Re: Lap prediction?

Post by Harry »

Yes, all algorithms around predicting times et al are well understood and implemented ;-)

I always try to understand the requirement and the best possible support for the driver first. Finding the IT solution is the final step. From what I understood from the above discussion is that average speed is limited once code XY is announced. It will mostly be measured on lap level only but one needs to keep in mind it can be done on any section too. So the best support is showing average speed starting at the point in time the code has been announced? Whether the limit is 60 or a different speed is something the driver will know and staying below that average speed displayed will be a good approach? Average speed starting at a point in time is easy to calculate because it is made up from distance driven since this point in time and the time elapsed since then. GPS Buddy has this build in already by the way, just select Trip View and press Reset. Buddy will show average speed starting at this time.

Some better integration in LapTimer and we are done? Any other suggestion?

- Harry
Image Image Image Image
Post Reply