Patent ID: 7184869

Claim:
A four-wheel-independent-steering-vehicle steering control method comprising: (a) using one of variables of steering constraint condition equations for forming a prescribed steering mode as a steering command value S and changing the steering command value S from a value S 1 to a value S 2 ; (b) computing incremental transition steering angles of four wheels [α 1 , α 2 , α 3 , α 4 ] S1+ΔS corresponding to a steering command value (S 1 +ΔS), which is the steering command value S 1 to which an incremental steering command value ΔS has been added, in accordance with the steering constraint condition equations; (c) changing steering angles of the four wheels α 1 , α 2 , α 3 , α 4 toward the incremental transition steering angles[α 1 , α 2 , α 3 , α 4 ] S1+ΔS ; (d) detecting a steering angle conformance, wherein the steering angles α 1 , α 2 , α 3 , α 4 have reached the incremental transition steering angles [α 1 , α 2 , α 3 , α 4 ] S1+ΔS ; (e) computing next incremental transition steering angles [α 1 , α 2 , α 3 , α 4 ] S1+2ΔS corresponding to a steering command value (S 1 +2ΔS), in accordance with the steering constraint condition equations; (f) changing the steering angles α 1 , α 2 , α 3 , α 4 toward the next incremental transition steering angles [α 1 , α 2 , α 3 , α 4 ] S1+2ΔS ; (g) detecting a steering angle conformance, wherein the steering angles α 1 , α 2 , α 3 , α 4 have reached the next incremental transition steering angles [α 1 , α 2 , α 3 , α 4 ] S1+2ΔS ; and (h) repeating above Steps (e)–(g) until the steering angles α 1 , α 2 , α 3 , α 4 reach steering angles[α 1 , α 2 , α 3 , α 4 ] S2 corresponding to the steering command value S 2 .