Week 17 (Feb. 6, 2019): Continuing Spartan Superway, Final Round

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Today was our first official Superway session following the move out of the old warehouse, our return from Winter Break, and the start of the 2nd semester of senior project. We had our first SPARTAN-Superway meeting as a whole class; Dr. Furman and Ron debriefed us on the updates since last semester, amenities of the new facility, and the ultimate goal of the project upon the conclusion of this semester.

Following our meeting, the class broke off into our three main teams (Full-Scale, Half-Scale, and Small-Scale). Our Small-Scale Team reconvened and set up a general shape and overall layout of the small-scale track, consisting of the cement posts and the rails. We also sifted through most of the boxes throughout the facility to collect and organize all of our equipment.

For the Small-Scale Controls Team, we recapped (and slightly readjusted) our plan for the first few weeks of the semester leading up to Presentation #1 on February 27.
  1. Ensure induction charger works (Completed)
  2. Make barebone circuit, including everything except the current amplifier. We would then show our prototype circuit to Dr. Furman and ask for some assistance with the SMT current amplifier.
  3. Implement revised Python code for GUI.
  4. Ensure successful Serial communication between the Arduino XBee and Raspberry Pi XBee.
    • Real-time location of each pod car
    • Distance between passenger pick-up location and closest pod car
    • Distance between passenger pick-up location and passenger drop-off location 

Over the Winter Break, we received: (1) the 12V, 600mA induction charger, (2) the LiPo mini-charger, and (3) a 3.7V LiPo battery. We ensured that they all do work by making a prototype of our circuit final: 5V power supply -> induction transmitter -> induction receiver -> LiPo mini-charger + 3.7V LiPo -> 12V [brushed] DC motor.

To recapitulate and clarify, the induction charger will be used to charge the LiPo battery.

We did not receive the 5V, 2A charger (our backup) until recently, so we still have to test it out. We would like this induction charger to work, so that we can charge the LiPo battery at a respectable 2A.

Running the 12V DC motor with the 3.7V LiPo battery made it rotate very quickly. So, we might end up simply using a 3.7V battery, as opposed to the larger 7.4V battery. However, we will have to use a smaller PWM value to tone down the speed, as we do not want the pod car to be running too fast.


Lastly, we slightly improved upon the GUI on the LCD touchscreen. We changed the options from “Select your drop-off location” and “Select your pod car” to “Select your pick-up location” and “Select your drop-off location.”

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