Track day in the sun

So today the team went to the sports grounds outside Trondheim Spektrum. The main goal of the day was to test the top speed of the car powered by battery. Testing the top speed indoors at Trondheim Spektrum is .. not advisable, so we decided to do it outside.

We had some software issues in the beginning, so it took a while before the car was up and running. Being efficient, Uwe and Tim utilized the idle time and went to the store and bought a barbecue grill and sausages. Meanwhile we were able to fix the software problems, and got the motor controller operational. As the grill was heating up, we took the car for an easy spin around the track. The first lap was done at around 10 km/h. Everyone listening intently for weird noises and looking to see if the wheels were coming off. The initial test went smooth, and after a final mechanical inspection we felt ready to crank up the speed.

Driving slalom between the children running at the track, we completed a few laps at around 50-60% of full speed or around 15-20 km/h. Everything was going fine, but as we had been driving for a while we decided to fully charge the main battery before going for full speed. Barbecue break killed idle time when the battery was charging.

When we were done barbecuing, the battery was fully loaded and all the kids had cleared the field. The sun had been out for a good few hours so the track had dried up from yesterday's slight rain. Up until now, the driver (Mats) had not been using seat belts, but the prospect of hitting the metal railing around the sports track at 30 km/t made him put on the 5-point harness. Also, when testing the car for the first time at full speed, we connected a laptop directly to the motor controller, not using the car's internal control system. This gave us much more control of the engine in case something went wrong. The trouble is that when stuff goes wrong, it goes seriously wrong: The worst thing that happens is that the engine locks up, locking up the wheel, making the car slide and flipping and/or hit the metal side rails. Motor lock can only really happen at full speed. No pressure there..

So, sitting in the car with a laptop, the driver controlled the speed in a computer program. Punching in the correct speed numbers in the correct fields in the data program was .. interesting at high speeds. The faster the car goes, the more the car shakes and the harder it was to control the laptop's touchpad. Using the laptop, steering the car, checking the speed and communicating with other team members called for some hardcore multitasking.

After some fumbling, the driver was able to push the car up to 80% of required full speed or 25-27 km/h. We tried to go faster, but then the motor controller gave up. It didn't fail as horribly as predicted - the engine didn't lock up. Still 80% of full speed is a great result for a first speed test!

At the end of the testing session Rachel Nordtmme, Northug's ex-girlfriend, suddenly appeared at the running track. Uwe had to work hard to keep our attention during debriefing.. After Uwe had sucessfully captured our attention for 30 seconds, we headed back to the office for a well-earned Friday beer.

All in all a good day at the office!

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06.mai.2011 kl.20:24

Hallo! nsker deg en superfin fredagskveld :-) Kos deg masse!

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