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Time to give it a body

A project log for ESP32 Mini-Bot

A small proof-of-concept ESP32 Bot

matthew-james-bellafaireMatthew James Bellafaire 02/21/2019 at 20:200 Comments

Let me just say, FreeCAD is a great tool. Coming from google sketchup for my personal projects this has been a breath of fresh air and just simplified the entire process. If you're looking for a good open-source (and more importantly free) CAD program then give FreeCAD a shot.

The body design for this project was fairly simple. the design had to fit the populated perf-board, hold a lithium ion battery, and support the wheel and motors. Here's what I came up with: 

without the cover:

Note: I never modeled the lithium ion battery into the design, it fits in the area below the board stand in. 

The model for this project went through a few redesigns. Originally, before the motors even arrived, the drive wheels were placed directly onto the motors. As a result that design never went anywhere quick and would frequently be a general pain to play with. Using the FreeCad plugin FCGears the rear wheels and motor mount were redesigned to have some reduction. This improved the performance of the bot considerably but not as much as intended. 

adding the geared wheels also required the wheels themselves to be moved down and back slightly. This resulted in the ridges seen on the bottom of the model. These ridges are far from ideal for a 3D printer and required the entire model to be printed with support material, adding another hour to the print time.

The wheels came out well, each wheel had as much material removed as possible in CAD to save on print time. On each of the wheels there is a groove intended for a rubber band to improve traction on the plastic surface which works well. 

Overall this design is alright, in hindsight i should have spent some time looking for better motors for all the trouble these ones have caused me. 

The STL files and FreeCAD project file are available for download on the main page of this project!

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