Visit my site for more information and pictures: http://pv-productions.com/rpm-meter-racing-car/
1. Info
In the period from February 2015 till Juli 2015 a 6 member strong team called "Torque Racing" participate in the accu drill race of Conrad here and here. They build an amazing racing car which they will race againt other team from all around the world in Linz, Austria on the 26th of June. The main requirement is to use 2 accu drills from Conrad without modifying them. They have done a really good job on that. Visit also their site for more information.
2. RPM-meter
A month ago they got in touch with me to collaborate on the electronics for the cart. They wanted a RPM-meter which should give feedback to the racer so he knows when to switch to the next gear. They did already some tests on the accu drills and measured that around the 200 RPM the drills are at it's maximum power. You can imagine that this should definitely add some value for the racer and the cart. With the requirements in mind I did some testing, came up with the hardware and programmed the controller. The controller consists out of one ATtiny85 set on 8 Mhz, a IR LED in combination with a IR phototransistor as sensor and 3 feedback indicator lights which light up on different RPMs up to 200 RPM. Also a ON/OFF switch with power indicator is included for convenience. The whole project is powered by a 9V battery and uses a 7805 to make 5V out of it.
3. The race 06-26-2015
A lot of effort, energy and engineering was put into this race-cart and they did an amazing job on designing it! Unfortunately they didn't win but the team Torque Racing has learned a lot along the process making this cart reality. Nice work! Here you can see the final results.
The whole build was documented with pictures on the Facebook page of DS-Design. Watch the trailer below.
4. Sponsors