Coin Picking Robot

The Challenge

To design, build, and program a robot that independently detects and retrieves coins around a predefined perimeter created by a wire carrying an AC current. It should be battery operated and pulls coins with a self-made electromagnet. The robot should be able to retrieve a total of twenty coins amongst nickels, dimes, quarters, loonies, and toonies. The project is to be done in a group five.

Building the Robot

The robot was built by splitting up tasks among the group members. After completing these tasks, we integrated all the parts together and tested the functionality of the robot.

The tasks were as follows: Coin-Picking Assembly, Perimeter Detector, Servo Motors and Electromagnet, and the H-Bridge with Optocouplers and MOSFETS.

Gathering Data

There were three primary sets of data that needed to be collected accurately for the robot to work as intended:

To determine the frequencies associated to coin values and referencing them to the current frequency input, in order to call an interrupt service routine for the robot to perform the necessary actions to acquire those coins.
To detect a differential frequency in the inductors when contacting the AC perimeter, so an interrupt service routine would execute and have the robot reroute itself away from the perimeter.
To count the amount of coins acquired up to the specification of 20, after which the robot would have an interrupt service routine and entirely stop the robot from any further action.

What I learned

This project gave me a deeper understanding of working with microcontrollers and helped me learn how to work with more complex circuits such as H-Bridges and Electromagnets. It helped me improve my uses of the engineering design process: generating the idea, implementing solutions, evaluating them, and iterating until the solutions are optimized.