Drag Race & Tractor Pull

To finish up the unit on gears, we had two team challenges. A drag race (test of speed) and a tractor pull (test of power). The first team challenge for the gears unit was the drag race. In this challenge, we had to make the robot that would go 3 meters in the least amount of time. To design the robot for the challenge, I first went with a 1:25 gear ratio with the standard task bot but found that the robot didn't have enough power to get started. I decided to not use a gear train and stick to a 1:5 ratio which would give me quick acceleration for the very short race. I also decided to add another motor which gave more power. I geared it the same as the others to prevent any problems from unbalance of power. The program I used was a very simple one. It had a sound sensor block in the beginning and then a forward for 3 seconds block with the coast button selected. To run the race, everyone had their program start on sound so we ran all the programs and played the beginning of a metallica song. This ensured that all the robots would start at the same time. My robot ended up getting across the line the fastest but it was very very close between me and Kenny. The next day we had the tractor pull. In this challenge, we had to build a robot that would pull or push the most weight 50 cm. in under a minute. To design the robot, I needed more torque and less speed. In this challenge, I made a gear train which gave my robot a gear ratio of 25. To get more friction between the robot and the ground, I put some weight on the front and back of the robot and I added extra wheels. My program was even more simple than the drag race. I consisted of a move block with the time box set for 60 seconds. For the first trial in the tractor pull, I decided to push 2 kg. My robot did this without even the slightest hint of it putting much effort in. After this, I decided I better do some testing to find out how much my robot was capable of pushing. It was able to push 7 kg with just a little bit of trouble so I decided that was the best weight to push for my final trial. My robot did it in 45 seconds. 7 Kg was also the highest in the class. All in all, these challenges helped us apply what we have learned about gears to something practical.