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|Target Environment||Locomotion Method|
|Sensors / Input Devices||Actuators / Output Devices|
|Front bumpers||DC gearmotors|
|Control Method||Power Source|
|CPU Type||Operating System|
|Time to build||Cost to build|
|URL for more information|
|Original Concept and primary goals
The task sounds simple enough: Motor drive a electric floor sweeper around the room and take the routine labor out of sweeping and vacuuming wood floors, and carpet. But as we found out by getting our hands dirty on this project, it is a much more complex task than cited above. Additional factors we had not fully considered included the perfect shape of the robot, changing the brush height, and what would be the minimum of a sensory array to accomplish its task. And finally but not least, the power requirements for effectively driving on thick carpet was unexpected.
While the details of VacBots construction has been documented in the earlier uploads on this project, our original concept remained the same: Take a proven industry standard push vacuum and make it self driven, and autonomous. The small size and amazing efficiency of the Red Devil brand push electric sweeper is well known among households today. We went through several iterations on driving the base around, which had a center of gravity not optimal for a well balanced robot. After giving up on belt drives, we settled on a nylon gear drive system with Jameco motors left over from our PAAMI project. The brackets and mounting were of Lexan and aluminum, with some brass for small parts. We mounted the microcontroller and motor driver H bridge in one box, with a split power supply. A 9v battery mounted with velcro on the outside of the box, and the rechargeable 7.2v battery which came internal to the sweeper was used for motor power.
It was found that while the motors did very well with the large wheels on hard floors, carpet was an issue because of the constant rotation maneuvers that would wear down the battery flat in less than 5 minutes. On a hard floor, that time was over an hour. The majority of testing for the final sweeping techniques was done on our hardwood floors.