I recently thought to look into coasting analysis and find a way to present this information in a way that was more impactful and visually provided a way to quickly focus on areas that needed improvement- after all, that is the power of these data acquisition packages, once you get past scratching the surface of these software packages.
Recently I was helping Lee (also the owner of Advance Motorsports) with a couple of his Porsche 997 Cup clients. As these drivers are at a fairly high level, most of the low hanging fruit for making improvements have been plucked. These guys are pretty good.
When you think about coasting for .4 seconds, that seems a fairly short time. However, if you then add speed into consideration, you might find that .4 seconds is a quite a long distance travelled.
His clients upgraded to Motec I2Pro which gave us access to powerful mathematical functions, so here is what I did:
Build a Coasting Channel that is true when the brakes are not applied and the throttle is less than 2%:
('Brake Status' <1 AND 'Throttle' [%]<2) == 1
Then, build a Coasting Begin Channel using the stat_start function. This will calculate the expression (using the built in Motec Corr Distance channel) when the Coasting channel is true:
stat_start('Corr Dist' [ft],'Coasting' [s] == 1,'Coasting' [s] == 0)
Then do the inverse to get a Coasting Over Channel:
stat_start('Corr Dist' [ft],'Coasting' [s] == 0,'Coasting' [s] == 1)
Finally, build the Coasting Distance Channel:
'Coasting Over' [ft]-'Coasting Begin' [ft]
There you have it. You can see in this screenshot that the driver at Lime Rock's uphill turn coasted for 173 feet and lost 7.9MPH. He could have braked latter and harder.