Individual Blog Week 7 (7/10 - 7/14)

This week was focused on 3-D printing a small rig for the tilting mechanism. Last week, I finished creating a control system to facilitate the pitch control of the bogie. However, before doing kinematic analysis on the design that I had for the bogie, my teammates and I decided to create a small rig to check whether this design would even be plausible.

I began testing the propulsion program on the actual bogie and started to run into some problems related to interference with the hall effect sensor. I attempted two different methods of switching. The first method causes the steering to occur at a specific time with the hall effect sensor detecting a magnet. The second facilitates the steering motion whenever there is a magnet detected. In the first method, the hall effect sensor kept detecting a magnet at a random time within the first few seconds of running. Afterwards, the program would continue as expected, but it messes with the count that we have within the interrupt function. The second method has a problem with interference relating to the relays. Every other time the relays click, the hall effect sensor detects a magnet. The relays emit a strong electromagnetic field whenever the channels open and close. I am considering having a low pass filter soldered onto the hall effect sensor PCB to attempt to counteract this problem.

Figure 1: Tilting mechanism in action
 

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Figure 2: Low pass filters on the limit switch PCB, which may need to be placed onto the hall effect sensor.

Figure 3: Isometric view of the entire system assembly in Solidworks. 


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