October 2nd

A DL1, strangely enoughWell I succumbed to some data logging gear, having decided after the Snetterton test that I need to get a bit more analytical about what the car's doing. I've been thinking for a while about getting one of Race Technology's DL1 loggers, especially as I could exchange the AP22 that I already had.

Well, I did, and here's a photo of the logger here. It provides:

  • a GPS receiver so you can see the route that you took around a track
  • longitudinal and lateral accelerometers so that you can see how much you're accelerating, braking and turning.
  • a collection of analogue and frequency inputs so that other things on the car can be wired up to it

The DL1 logs data straight to a compact flash card (as used in many digital cameras) which means it's very quick to get the data into a PC for analysis.

So, I spent today wiring it up to the car, as least in an initially fairly minimal way. In addition to the GPS and accelerometers I wired it up to log engine rpm, throttle position and wheel speed. (Although, the latter is really just for interest to compare it with the speed derived from the GPS receiver.) I positioned the logger on the floor of the passenger side of the car, as I guess that's not too far from the centre of gravity. I haven't quite worked out where the GPS antenna itself should go. At first thought I thought I'd have to put it on the top of the roll cage but it seems to work well enough (it was even working in my garage with the door shut, although not to too high a level of accuracy) that I might be able to put it on the floor, next to the logger itself.

A graphFinally, I tested the logger. I couldn't actually drive the car around, although I thought about taking it for a ride on the trailer, so I just played about with the rpm and throttle position sensors. This graph here shows the rpm and the throttle position with the engine just being blipped in the garage.

The top trace is for the throttle position, the bottom for engine rpm. You can just about see that the throttle position leads the rpm trace slightly. Bike engines do have some inertia, just not much.

So far, I'm very pleased with the DL1. It wasn't exactly cheap mind... I now need to see if I should buy some more tyres before the Snetterton races, and whether I should spend even more money on testing.

October 7th

Well, I don't seem to have shelled any more dosh for testing yet. I probably won't either as I could really do with saving some money. What's more, testing at Snetterton seems very expensive.

Ready to eat DL1One thing I have done is made a little house for the DL1. I got a bit worried about what would happen if it rained at Snetterton (it usually does) so arranged for the DL1 to be encased in this little cast off food box.

Yes, I know it's still going to leak even though I do plan to fit the lid but not as much as the sky. I suppose it could fill up though which could be unfortunate.

The problem with the DL1 is that as there accelerometers are actually in the box itself it ideally needs to be firmly attached to the car itself. However, after finishing this I did think that putting it on top of the right hand sidepod would make sense as it would probably still count as sufficiently firmly attached and it would be easier to reach the controls. Also, another modification for the winter is to put some remote controls for it on the dash. Probably a power switch, a start/stop logging button and a "logging now" light. The rear panel already has connections for these which is good.

A cleaned up FuryFinally, in preparation for the racing at the weekend, I washed and polished (!) the car. If nothing else, the polish gets all the rubber smears off the rather iridescent yellow bonnet.

Hopefully, the weather will be ok this weekend and I don't bend or break the car. If so, it will probably be a nice end to the season.

(Unless, of course, I decide to do Mallory after all....:-)

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