Variable Frequency Differential Capacitance Sensor Digital Detection Circuit

A Variable Capacitance Touch Sensor

Tactile feedback is useful in performing many robot manipulator tasks. This paper describes the simple touch sensor used on the robot manipulator at the Coordinated Science Laboratory. This sensor has a range of 1 to 80 ounces with a resolution of about 0.2 ounces at the low end of the scale. It is inexpensive, easy to construct, and relatively free of hysteresis, drift and fatigue. Also, the o...

High-speed interface circuit for differential capacitance transducers

A high-speed capacitance difference-to-sum ratio measurement circuit is presented for differential capacitance transducers. It consists of a switched-capacitor input stage, two sample-and-hold (S/H) circuits followed by voltage-to-current (V/I) converters, and a current-ratio-controlled relaxation oscillator. This circuit offers a square-wave output whose oscillation period is directly proporti...

Design of Interface Circuit for Differential Capacitance Measurement

Optimization Shape of Variable Capacitance Micromotor Using Differential Evolution Algorithm

A new method for optimum shape design of variable capacitance micromotor VCM using Differential Evolution DE , a stochastic search algorithm, is presented. In this optimization exercise, the objective function aims to maximize torque value and minimize the torque ripple, where the geometric parameters are considered to be the variables. The optimization process is carried out using a combinatio...

A sensitive differential capacitance to voltage converter for sensor applications

There is a need for capacitance to voltage converters (CVC’s) for differential capacitive sensors like pressure sensors and accelerometers which can measure both statically and dynamically. A suitable CVC is described in this paper. The CVC proposed is based on a symmetrical structure containing two half ac bridges, is intrinsically immune to parasitic capacitances and resistances, is capable o...