Individual Blog Week 3 (6/12 - 6/16)



During this week, I had to begin creating a test rig and getting parts machined to improve the bogie. Parts such as shafts, jackets, spacers, and gears were sent out to both the central machine shop and the ENGR 123 in the engineering building. The jackets and spacers had a quick turnaround time and I was able to retrieve them quickly. However, there will be a long wait on the shafts and the gears, due to the amount of orders that the central machine shop machinist has.

As for the mechatronics portion of the robot, I was able to begin building a test rig to emulate the half-scale bogie. First, I began by utilizing the hall effect sensor, and two DC motors. This will emulate the propulsion of the half-scale bogie. When the hall effect sensor encounters a magnet, both of the DC motors stop moving. Afterwards, I used a different Arduino to emulate the steering of the half-scale bogie. When the limit switch is pressed, the stepper motor starts rotating. Combining the two proves to be a bigger challenge, because the limit switch sends a magnetic signal to the hall effect sensor. Next week, I will figure out a way to filter out the limit switch signal. Another problem that presented itself was the lack of a reliable power supply, which will also be solved next week.



Figure 1. Two DC Motors and a Hall Effect Sensor
Figure 2. Stepper Motor, RGB LED, and Limit Switch


Figure 3. Test Rig With Components From Figures 1 and 2





































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