Fig 1.
Electric power steering system.
Table 1.
Technical symbols.
Fig 2.
Vehicle dynamics model.
Table 2.
Vehicle specifications.
Fig 3.
Ideal assisted map.
Fig 4.
Proposed control scheme.
Fig 5.
Genetic algorithm workflow.
Fig 6.
(a) e1 input; (b) e2 input.
Table 3.
Fuzzy rules.
Fig 7.
(a) Fuzzy surface for kp; (b) Fuzzy surface for kd.
Fig 8.
(a) Driver torque; (b) External disturbances.
Fig 9.
Change of EPS outputs (v1 = 25 km/h).
(a) Steering column angle; (b) Steering column speed; (c) Steering motor angle; (d) Steering motor speed.
Fig 10.
Change of assisted performance (v1 = 25 km/h).
(a) Assisted current, (b) Relationship between assisted torque and driver torque.
Fig 11.
Observed disturbances (v1 = 25 km/h).
Fig 12.
Change of EPS outputs (v2 = 70 km/h).
(a) Steering column angle; (b) Steering column speed; (c) Steering motor angle; (d) Steering motor speed.
Fig 13.
Change of assisted performance (v2 = 70 km/h).
(a) Assisted current; (b) Relationship between assisted torque and driver torque.
Fig 14.
Observed disturbances (v2 = 70 km/h).