A robot includes a body and a bumper. The body is movable relative to a surface and includes a first portion of a sensor. The bumper is mounted on the body and movable relative to the body and includes a backing and a second portion of the sensor. The backing is movable relative to the body in response to a force applied to the bumper. The second portion of the sensor is attached to the backing and movable with the backing relative to the first portion of the sensor in response to a force applied to the bumper. The sensor is configured to output an electrical signal in response to a movement of the backing. The electrical signal is proportional to an amount of displacement of the second portion relative to the first portion.

A capacitive sensing device is provided with a plurality of pads disposed on a base around a center of the base; a ground plane positioned above the plurality of pads; a rotor, positioned between the ground plane and the plurality of pads, configured to at least partially rotate about the center resulting in a portion of the rotor being positioned over different portions of the plurality of pads at different angles of rotation; and sensing circuitry connected to the plurality of pads in order to determine a position of the rotor; and wherein at least two pads of the plurality of pads are disposed in a shared arc defined from the center.

A capacitive rotary angle measuring system for detecting a rotary movement of a shaft includes a sensor unit, a carrier signal generator, an evaluation unit, and a carrier signal adaptation unit. The sensor unit includes a transmitting electrode arrangement and a receiving electrode arrangement which are capacitively coupled together, and a coupling device which co-rotates with the shaft and which varies an electric capacity between the receiving and the transmitting electrode arrangement based on a rotational position of the coupling device. The carrier signal generator is electrically connected to the transmitting electrode arrangement and generates an electrical carrier signal. The evaluation unit is electrically connected to the receiving electrode arrangement and senses an electric measurement signal generated at the receiving electrode arrangement and determines a current rotary angle measurement value. The carrier signal adaptation unit adapts a carrier signal frequency value based on a provided interference frequency value.