June 2 through 6

This is new suspension for the locomotive. It can support over 400 kg. I weigh 105 kg. In last years competition, the team suffered point deductions due to the lack of dampening in their frame. This year they went with solid rubber spacers to act as a suspension. It seems to work great! 

This week I also spent time on the controller, learning more about microbasic. It's a steep learning curve and since no one here knows how to program in this language, it's all up to me to learn it. I was able to make the motor run with the script using a throttle plugged into the controller. The next step in programming the controller was to write a script for regenerative braking. This is when the locomotive is going downhill or braking. In order to collect the most energy, the motors need to be supplied with enough power to eliminate the torque restraint. To help with this task I used an online example provided by RoboteQ where they had regenerative braking on an electric scooter. To test the code, we needed to build a rig to house the motors and connect a chain to both motors. One will act as the driving motor and the other will be used to provide resistance or make it speed up as if it were going downhill. In order for the code to work, the tachometer needed to be attached to the motor. So, as simple as it sounds, we placed the tachometer in it's brace on some pieced of wood and attached a plastic piece to the motor axle with some tape. It was just fine for low speed testing. 

The hydrogen fuel cell needs to be run every couple of weeks for maintenance purposes. We attached the dolly wheels and the fuel cell to wheel it outside for testing. To test it, simply provide hydrogen, connect to existing power, for this model it's 48 volts DC, and the fuel cell turns on and starts using hydrogen to provide electricity at 48 volts DC. This model is an 1100 which means it's rated for 1.1 kilowatts. It runs at 80% efficiency and it's 5 years old so at the end of the day, it's putting out 700 watts of power. Plenty for our purposes. The power supply for the locomotive is four, 12 volt, 90 amp hour batteries (car batteries) wired in series to provide 48 volts. The fuel cell is directly connected to these batteries and keeps them full charged. When the locomotive is in it's typical opperation, not needing much power, it pulls it's power from the fuel cell. When it needs a lot of power for instance, going up a hill, it can draw power from the batteries. We will be putting the batteries on the locomotive next week to see how they fit.