canometer - measuring can

12-30 — elektor december 1980 canometer measuring can S. Heilmann The fact that a can has volutational properties was the inspiration behind this particular design in which the roll plays a very important role. The circum- ference of the can is used to measure distances with a fair degree of accuracy. The distance covered, or rather, rolled is indicated on a four digit display, the maximum readout being 99.99 metres. Distances can be measured in three basic ways : by using a ruler, a tape measure, or by electronic means. The first two are often time consuming and prone to inaccuracy and the third is relatively expensive. A fourth possi- bility is now provided by none other than this canometer, its prime merit being simplicity. It is, in fact, just an electronic meter incorporated into an empty can and which indicates the measured distance on a digital display. The principle behind the circuit could hardly be more basic. When a cylinder is rolled along a flat surface, the distanc...