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Week 29 (May 1, 2019): CAD of Induction Charger Hub & Podcar Door, then 3D Printing

This week, while David worked on the Raspberry Pi and the Arduino code, Patrick completed the CAD (computer-aided-design) models. We had to create 3D solid modeling of two parts: the induction charging hub to hold the induction transmitter coil and the pod car door to hold the induction receiver coil. Over the weeks, the CAD models underwent several revisions.

The induction hub saw two revisions, with the third design being the final version. Because the 3D printer available to us in the shop, the Prusa Mark3 i2, had a bed length of 10 inches, we had to restrict the length of the charging hub to a safe 9.5 inches.

Version 1 simply entailed us placing the hub on the side of the bracket and then screwing it into place on the bracket’s side via the two holes at the top:


For version 2, in addition to placing the hub on the side of the bracket and then screwing it into place on the bracket’s side via the two holes at the top, the bracket would wrap around the two brackets. Furthermore, while the first version was designed to reach a specific height, version 2 was designed to allow for height adjustment. This was made possible by cutting out slots on the side flanges of the hub:



Version 3, the final version, features another addition by allowing for adjustment of the distance between the hub and the podcar. This was done by separating the hub into 2 pieces: the T-shaped foundation piece that will be screwed into place to the side of the bracket (the part colored dark purple in the image below), and the spatula-shaped hanging piece that will slide along the foundation piece for the depth adjustment (the part colored light purple in the image below):



As a reminder, there will be one induction charging station in each of the two offline stations, i.e. offline rails:

The second part to be modeled was a new pod car door to account for the addition of the induction receiver coil, which was accomplished by adding a hole on the existing pod car door:

Our 2D detail drawings of the induction charging hub and the pod car door are shown below:


On a final note, we were able to get everything 3D printed – the two charging hubs and the three pod car doors for each of the three pod cars – at the Maker Space. We would not have been able to finish our project if it wasn’t for their help, so we would like to express extreme gratitude to Maker Space.   

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