Electric power assisted steering (EPAS)

Concerns electric power-assisted steering (EPAS) of cars. There are more small cars than in the past, and most are front wheel drive, placing a large proportion of the weight of the car on the front wheels. This makes it desirable to fit the smaller cars with power assistance to the steering. A PAS system in smaller cars would also help maneuverability and for reducing driver fatigue. However there is little room to fit large hydraulic pumps in the smaller cars, and their small engines do not have sufficient spare power to supply a hungry hydraulic system, so an electric system is ideal. At the heart of EPAS systems lie an electric motor which needs to be controlled electronically to assist in the steering action by just the right amount. This paper discusses how DSP controllers can benefit this application by offering a single-chip solution to a complex problem of control.