A Rotary Variable Differential Transformer (RVDT) is an angular position sensor that produces an output voltage proportional to the angular displacement of a laminated rotor stack. This rotor is mounted on a stainless steel shaft that when rotated, moves the rotor to direct greater flux into one secondary of the stator windings thereby increasing the voltage and reduces the flux in the opposing secondary.
The output wave form is a sine function. A full 360° rotation of the shaft will result in either one or two sine wave cycles depending upon the RVDT design. These different designs are referred to as either single cycle or dual cycle RVDTs. The usable linear range for the single cycle is ±80° around electrical zero. The linear range for the two cycle is ±40° around the zero, with the two cycle exhibiting higher accuracy. These angular sensors typically provide MTBFs higher than any other type of angular sensor.
Features
- High reliability (MTBF of 1,000,000 hrs. typical)
- High accuracy (± 0.25% full scale)
- Stable output as high as 80g vibration
- Pressurized & hermetically sealed designs available
- Precision alignment or coupling features
- Angular & rotary measurements
- Single cycle (± 80°) or dual cycle (± 40°)
- Non-contact brushless rotor design
- Infinite angular displacement
- Size 8 or size 11 servo or flange mount
- Lightweight, robust designs, small package
- Constructed for stability and interchangeability over its life
- Qualified to RTCA/DO-160 and MIL-STD-810 specs
Applications
- Flight control actuators
- Hydraulic & Fuel Valves
- Nose wheel steering systems
- Cockpit controls
- Engine bleed air systems
- Fuel controls
- Fly-by-wire systems
- Brake-by-wire systems
- Environmental control systems
- Thrust reverser
- Engine control actuators
- Engine fuel control
