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Week 13 (Nov. 21, 2018): Pre-Thanksgiving Meeting – Max Charging Distance & Max Motor Acceleration


Although there was no meeting for any of the ME 195A students today due to the Thanksgiving break starting holiday tomorrow, I wanted to plan for the final presentation, Presentation #3, and complete some calculations that we all could include in our presentation slides.

I bought both the 12V, 600 mA and 5V, 2A induction charging modules, just in case one does not ultimately work out. However, we will try the 12V, 600mA one first. The max charging distance of the 12V, 600mA induction charging module is 20 mm, or 0.787 in. This max allowable distance should be accounted for when we design the charging station and/or hub with the Small-Scale Track Team. Recall that The Small-Scale Track team is planning to construct a Y-bend located in the middle of the track, and then together, we will create and install at least two induction charging stations within the Y-bend, acting as a sort of “pit stop”.

Also, I calculated the max acceleration that the gimbal motor will experience resulting from the 7.4V of the battery. Ideally, we want the pod car to move at a constant speed throughout the rest of the trip. So, the only acceleration we have to consider is the start-up acceleration to speed up from rest to the max velocity. The max velocity, given 7.4V, is 1.051 m/s. We can then say that we want to accelerate for about 2 seconds. So, the acceleration would be:




So, this would be the max acceleration if we want to accelerate to the max speed in 2 seconds. The Bogie Team will have to account for this when designing the wheels.

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