by Doyle Maleche
One of my many projects is a robot I call “The GardenBot”. I’m building this for my wife, Carol to work around the yard so she will not have to carry heavy tools, dirt, fertilizer, etc.
The concept behind the GardenBot is fairly straight forward; my wife carries her small light-weight garden tools in the bright orange Home Depot bucket. The GardenBot’s computer vision system tracks the bucket and drives the motors to follow it – pulling the garden wagon loaded with heavy gardening materials and tools. The GardenBot will autonomously maintain a 4 foot distance from the bucket and wait until the bucket moves, then start following again. The GardenBot gets bored when the bucket is not moving and will start to nag my wife with; “Move the darn bucket!”, “are we there yet!”, “Daisy, Daisy, give me your answer do…”,”I can’t do that Dave…”, sing “If I only had a brain…”, ”I want some candy!”, “I have to go potty!”, etc. (sound familiar parents?)
The prototype was built using a donated robot lawn mower from my good friend, Bill Webb. This is the model RL-500 from Friendly Robotics (Figure 1). I removed the OEM control board and cutting motors and developed the tracking algorithm to test the software and capabilities. It currently has a Dimension Engineering 2×10 controller (older version), and Asus NetBook running the computer vision software from RoboRealm. This version is about 60 pounds and is safer when testing the software and doesn’t hurt as much when it runs into me. This also incorporates a “pilot” or First-Person-Viewer (PFV) camera mounted above the batteries and long-range 3000 ft. video transmitter. I have future plans to control this bot up to 4000 feet and mount a big 6 axis ScorBot III robot arm (Figure 2.) and will christen it the “Cerberus “. Cerberus will autonomously roam the property and track, report, and alert when an unwanted visitor is detected on my property. Oh yeah, It will also go to the mail box and retrieve mail.
The final GardenBot version will be constructed using the tread-based Trac-Drive from a disassembled Craftsman Snow Blower (Figure 3.) and powerful electric wheelchair motors, Dimension Engineering Sabertooth 2×60 (dual channel 60 amp) dual motor
controller, Pololu 6 channel servo controller, Asus 1Ghz NetBook running the control software, and pan/tilt servos to control the tracking USB camera. The finished GardenBot is expected to weigh about 200 pounds with two on-board 12volt batteries in series supplying a total of 24volt DC for the power train and system power. My YouTube channel (Scruffman2001) will show the robot and other projects in action. See you at the Maker Faire!