Week 6 (Oct. 3, 2018): Coordination with the Small-Scale Bogie and Track Team

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Today, we discussed overlapping aspects of the small-scale system with the bogie team and the tracks team.

The track team has settled on a design for the new track: a rectangular shape track with a Y-junction junction in the center to accommodate two charging stations, one at each branch. We are hoping to implement induction charging at these stations, which requires a 3.7 V Li-ion battery. Something else to consider is if we can use a transistor to amplify the current draw from the induction charger to speed up charging of the Li-ion battery and if we can use a boost converter (step-up transformer) for the brushless motor we will use.

With the bogie team, we discussed motor sizing, as this selecting the appropriate motor would affect the force that the wheels would experience, and thus the design of the bogie. The force of the motor would be found by: (1) determining the power supply current output to the motor, I; (2) converting the speed constant, KV, which is provided in the motor specifications, into torque constant, KT; (3) multiplying the current and the torque constant, KT, to yield Torque, T; (4) Solve for Force by dividing Torque by radius and the sine of the angle between radius and Force.


This force of the wheels would then be put into an FBD, along with the weight of the pod car and friction force. Finally, the coefficient of friction would be found.

Comments

  1. Eric HagstromOctober 8, 2018 at 3:54 PM

    Excellent post by the Small Scale Controls Team! Please begin adding links to your code (include detailed comments on how the code works) and other hardware (sensors / actuators, etc) that you are using for your controls system. In addition, please create detailed wiring diagrams when the time comes to breadboarding or creating PCBs.

    ReplyDelete
  2. Eric HagstromOctober 15, 2018 at 9:58 AM

    The Small Scale Controls Team has missed their last blog post. Hopefully your team will keep up with this blog. Points will be reduced.

    ReplyDelete
  3. Eric HagstromOctober 15, 2018 at 10:07 AM

    Per the schedule (posted by me on the main SpartanSuperway.blogspot.com), your team should be well underway of designing your controls system. This week, I would like to see your progress on how far your team is.

    What is the progress on your code? Wiring schematics? Induction Charging calculations?

    ReplyDelete

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