Steering Sensors: Working Principles of EPS Systems

Prior to the widespread use of power steering in motor vehicles, driving involved significantly more physical effort on the driver’s behalf. This was due to the entirely mechanical steering system which comprised of a steering wheel, a column connected to an intermediary steering shaft, and the steering rack which turned the wheels. Turning the car was entirely based on human effort. Things changed in the 1950s when Chrysler introduced the concept of power steering to the automotive world, under the brand name ‘hydraguide’. Although revolutionary, steering sensors and electric power steering (EPS) were still decades away.

Drawbacks of Hydraulic Power Steering

Hydraulics formed the underlying principles of early power steering, introducing a power ram between the column and the steering rack. This ram pushed left or right depending on the position of a control valve connected to the steering shaft. The pressure was supplied by a pump that was run by an additional engine belt. While an integral development for the automotive sector, hydraulic power systems are not the most economical method of augmenting human steering effort.

How Do EPS Systems Work?

EPS systems provide a range of benefits over both non-assisted, purely hydraulic, and hybrid steering systems. Rather than an engine-powered motor, EPS systems utilize an electric motor with a series of steering sensors for dynamic assisted steering without a parasitic loss of engine performance. Steering sensors within the EPS system sense both the position and levels of torque applied to the column when a driver turns the wheel and software converts those signals into a commensurate output through the motor. This is a more dynamic and energy-efficient method of assisted steering.

Steering Sensors Used in EPS Systems

Three primary different steering sensor types make this outstanding level of performance possible: Steering position sensors, steering torque sensors, and steering sensors that offer a combination of the two.

The two key driver inputs that these steering sensors monitor are the steering wheel angle and the amount of effort applied to the turn. After assessing these input signals, motor electronics algorithmically generate a responsive output, providing intuitively responsive assisted steering. A wide range of these integrated steering sensors is available for an increasingly diverse global automotive industry.

Steering Sensors from TT Electronics

TT Electronics is a world leader in the manufacture and supply of steering sensors for a changing marketplace. We provide continual improvements to long-established systems, helping engineers develop more dynamic and efficient motor vehicles than ever before. Our broad range of steering sensors covers both magnetic and contacting technologies, with positioning angles from 360 – 900° of rotation. Each is compact, with limited wiring to maintain the small form factor that has proven so integral to the success of modern EPS systems.

Common Mode Chokes from TT Electronics Are Ideal for Automotive EPS Noise Suppression Applications

If you would like to learn more about our range of steering sensors or have questions about using our products in automobiles as varied as electric and hybrid electric vehicles (EV/HEV), diesel and petrol cars, or heavy industry and military vehicles simply contact a member of the team today.

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