Patent ID: 7036241

Claim:
An electronic measuring device for measuring length or distance along a surface, the device comprising: at least one wheel assembly for engaging and rolling on the surface; the wheel assembly comprising an encoder; the encoder comprising a plurality of circumferentially spaced-apart markers, the encoder passing between an emitter and a receiver when the wheel rotates; the emitter and receiver being linked to a controller, the controller computing the length or distance traveled by the wheel by counting the number of markers that pass between the emitter and receiver, wherein the emitter and receiver are both mounted to a first printed circuit board, the first printed circuit board being linked to a second printed circuit board that is connected to and supports the controller, wherein the second printed circuit board is linked to a plurality of control bottons, wherein at least one of the buttons operates to activate a computation by the controller to divide the length or distance previously computed by the controller into a plurality of segments, and wherein as the device is rolled back across the previously measured length or distance, the controller provides an indication when the device is traversing between one segment and a succeeding segment.