Capacitive position sensor

摘要

A transducer includes a plurality of electrodes and a dielectric shuttle. The dielectric shuttle passes between a subset of the electrodes, modifying the capacitance between them. By measuring the capacitance of subsets of the electrodes, the position of the dielectric shuttle may be determined.

主权项

1. A method for measuring position, the method comprising:
arranging a dielectric shuttle such that it is at least partially between a common electrode and a first sensing electrode, the dielectric shuttle having a first dielectric constant portion and a second dielectric constant portion with different relative permittivities, and being arranged with a first percentage of the first dielectric constant portion and a second percentage of the second dielectric constant portion located between the common electrode and the first sensing electrode; sensing a first capacitance of the common electrode in combination with the first sensing electrode, the first capacitance being based on the first percentage and the second percentage; moving the dielectric shuttle relative to the first sensing electrode such that it passes between the common electrode and a second sensing electrode, with a third percentage of the first dielectric constant portion and a fourth percentage of the second dielectric constant portion located between the common electrode and the second sensing electrode; sensing a second capacitance of the common electrode in combination with the second sensing electrode, the second capacitance being based on the third percentage and the fourth percentage; and measuring the position of the dielectric shuttle based on the sensed first and second capacitances.