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The project aims to reshape the mobile base OTTO and re-program a low-level control program to reduce excessive oscillating motion of the rear free wheel. At the current state OTTO is a three-wheeled vehicle with two front driving wheels. Our long term goal is to make OTTO a four-driving wheeled vehicle. Furthermore, the current frame of the robot is too small to permit the two motor to fit in series in a horizontal line and so we want to enlarge and standardize the frame. OTTO also doesn’t have a safety arrest system for electrical malfunctions and so we want to add it.
Below there is a step-by-step list for the implementation defined above
- Disassemble OTTO measuring the parts and put them into a CAD system, for easing future work.
- Modify the existing low-level control system so to obtain a reduction in the oscillation of the rear free wheel (first trial is in activating and tuning the part of the control program based on cross-checking the errors in the measured speeds between the driving wheels.
- Creation of a shutdown system in case of electrical malfunction of type "too much current into the motors".
- Enlarge the skeleton to allow the engines to fit without overlapping.
- Build a new frame (same width as the front one, but shorter) for the rear wheels.
- Find or design a pivot to allow the front and the rear frame, and so the front and rear wheels, to roll independently w.r.t. an horizontal longitudinal axis, so the wheels remain in contact with the ground.
- Mount the motors, ball-bearings, chains and pinions, wheels, tires, etc. on the new rear frame.
- Remove the third wheel and the shaft that supports it, and mount the pivot and the rear frame.