Resistor-Based Shape Sensor for a Spatial Flexible Manifold

In robotics, knowing a mechanism's configuration is essential. Commonly, potentiometers or encoders are used in order to obtain the mechanism's configuration. Nevertheless, such sensors are useless for applications where a surface's spatial-shape is to be attained. For that end, we introduce a novel sensor mesh. We use an electrical-resistors grid as the shape sensor. The resistance in each grid segment changes with accordance to its length. So, by attaching the sensor mesh to an elastic grid, bending results with resistance change in the associated segments. For practical reasons, only the peripheral nodes are wired. We introduce an algorithm to extract the resistance of each of the segments. We then formulate the forward kinematics of elastic grid mechanisms which later on, we apply, in order to obtain an estimate for the surface shape. We exemplify our algorithm on a 40 resistors grid.