This is my first robot. He is equipped with one IRPD, in which IR is reflected off an object and the reflection is detected by a receiver. After Neophyte's fist test run, I noticed that the wheels sometimes got snagged on a chair leg and tipped over the 'bot. Soon after I added two touch/whisker sensors to protect the wheels.
One of my faults in this robot was to put the battery pack behind the servos, therefore making the robot a little "tipsy". This was partially fixed by adding counterweights (washer and other hardware) to the front end.
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