Poly Robo Trimmer

Sponsored By: Cal Poly/First Solar
Student Team: Drew Felker (MATE), Cal Hayenga (IE), Juan Jimenez (MATE), Ross Miller (ME), Elliot Tham (EE), Bryce Zakoski (BMED)
Faculty Advisor(s): Dr Richard Savage (MATE)
Project Completed: June 4, 2009

Throughout the project there have been changes that our initial conceptual design has undergone. These changes come from needing to scale back our project due to cost issues. The major changes that were made in the design were to switch from a track system to a skid-steer wheel drive system, reduce the number of batteries, and incorporate a smaller brush cutter. Making the above mentioned changes reduced the cost of our prototype by approximately than 50% when compared to our initial conceptual design, now making the cost approximately $6300. After making the needed design changes we then built the robot to satisfy the modified design requirements. The purpose of this document is to present the details of our design plan, manufacturing process, and testing of the robot. To help manage the project we have broken down the overall design of our robot into the following assemblies: Frame, Wheels, Drive train, Brush cutter and Electronic controls.

The frame for our design is being considered as the robot platform. It is where the components for the robot will be attached or housed. Off-road wheels were chosen for the rough terrain we would like our robot to navigate. The drive train is composed of the necessary components (motors, drive chains, etc.) which will propel the robot. The brush cutting device we are using is from a DR Scout brush mower which we are incorporating into our design. The electronic controls portion of our design is where the control of the robots movements takes place which includes speed controllers, fuses, and the remote control system. As each assembly is presented, the individual parts which make up the assembly is identified and the functionality of the parts are described. 3-D solid modeling and detailed drawings are used to present many of the details.

As the prototype was built there were a series of tests that ensured the performance of the different components and assemblies. The tests aimed to test the performance of the motors, batteries, and drive train. Along with the performance tests, there will be an emphasis placed on safety. A remote controlled clutch that stops the blade from spinning and a master kill switch on the robot that shuts off all power to the motors were two systems designed to keep users safe.

In addition to the design details and tests, a timeline showing project progress over the past nine months is addressed. The timeline shows how the group effectively planned and used its time to create the working prototype.