BISHOP TORQUE AND ANGLE SENSOR (BTAS)
BTAS is an advanced opto-electronic sensor for use in electric and electro-hydraulic steering systems. It reliably measures torque and absolute steering angle at a high accuracy and resolution.

BTAS uses CMOS technology in a customised opto-ASIC (Application Specific Integrated Circuit) that provides unrivalled resolution and accuracy. Absolute angle is measured to 16 bit resolution, equivalent to better than 0.01 degrees.

It is essentially a digital measurement device and does not suffer the drift experienced with most analog torque sensors and is also relatively insensitive to electromagnetic interference. It is being developed for underhood application.

Unique design and assembly features mean that no calibration is required, either during manufacture or in service.

  
VARIABLE RATIO (VR)
All of the vehicle dynamic benefits of VR in manual and power steering apply to electric steering applications. However, VR also offers additional design benefits for Column and Pinion driven electric steering applications.

Two of the main obstacles of electric steering are electric current requirements and motor size (torque rating). Bishop's VR allows designers to optimize the mechanical advantage of the rack and pinion for on center driving and parking. Steering geometries require higher forces to turn the wheels during parking maneuvers with straight ahead (on center) driving. With VR, designers can increase the mechanical advantage off center (parking), which in turn reduces the electric current and motor torque requirements of the system.

Bishop's warm forging of VR allows the fastest and largest ratio change available. Ratio changes of 50% within 90 degrees of steering wheel turn are possible.

A vehicle, which handles more responsively and requires less physical movements to control, is much safer and more pleasant to drive. VR steering enables the chassis engineer to achieve the optimum suspension characteristics for both safety and comfort.