Individual Blog Week 2 (6/5 - 6/9)

During this week, I made a lot more progress towards redesigning the mechanical portion of the steering on the half-scale bogie. The 0.5" diameter 4140 steel rod and other parts arrived this week, and my team was able to utilize the miter saw to cut portions of the steel off. Although not all of us have access to ENGR 123, we plan to finish fabrication as soon as the door codes are sent to us.

As we wait for door codes, I have been looking into implementing regenerative braking for the half-scale bogie. This would yield at least a ten percent efficiency in regeneration (back to the battery) due to the nature of the brushed DC motor. I am considering replacing the H-bridge in favor of a full bridge rectifier and MOSFET combination that utilizes N-AND logic gates to act as switches. I do not believe that we would require a PWM generator because the duty cycle is either at 0% or at 100% (most likely because it is a two phase DC motor). This configuration allows for a more compact setup for mounting.

The last thing that I have been researching is a new mechanical braking system. The past braking system simply used a caliper to clamp onto the wheel. However, this did not work and would promote wear onto the wheels. I am considering either hydraulic or ABS braking, depending on how fast we can finish fabrication.

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