Team E determined that a servo motor would be beneficial and worth looking into for experimentation. The Servo was then determined to be used for a method of braking. Then Brake testing with the servo became the first of two experiments for team E. The servo would be used by adding an arm below the track the would hold different “brake pads” then this data would be compared to coasting and reversing the main motors for effiency and accuracy. Below the team will discribe the experiments used and their results.
Experiments
Coasting:
While testing the coasting, the team would get the AEV to a set speed and then set the power to zero. The team then recorded the time and distance it took the AEV to come to a complete stop.
After the experiment the team determined that coasting was not an effect way to stop the AEV. This was due to inconsistancies with stopping distance and time which could overall negatively affect the final results of the AEV.
Power Braking:
Power braking is when the AEV’s motors are reversed until a complete stop is reached. So to test this we had the AEV reach the same speed as before and then reverse to motors and record time, distance and power usage.
After the experiment, the team determined that while power braking is more effective and reliable than coasting, it did use much more power. Overall the team decided that power braking was better than coasting because although it used much more power the accuracy was needed to complete the tasks.
Servo Braking:
The team decided to use the servo provided to try and make a braking system for the AEV. The team determined that using an arm on the servo with an eraser as a brake pad would be the best use.
At first, the team used a small pencil eraser for the brake pad. It was found to be most effective between the tests. This was because ther eraser both accurate and power effective. It was accurate because the eraser made it possible for the AEV to come to a stop very quickly while also being effercient because the servo did not use much power.
Although to initial testing was appealing the team wanted to go further. So, the team decided to test another brake pad. This time a large eraser cut in half was used.
After these tests the team decided that the larger eraser was better to use. This was because it could come to a quicker complete stop while using the same power as the small eraser.
Conclusion
As a result of the above experiments, Team E found that a servo with a large brake pad would be the most effective way to both use the servo function and for braking the AEV. This was because servo braking was much more accurate than coasting while using a little more power, yet the accuracy was worth it. The servo was also determined to be better than power braking because it used much less power than reversing the motors, also it was more accurate because power braking still included coasting. This is because coasting went 5 meters and servo function went 2 meters