Anti-spin control system

A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels comprising:

• means for generating a signal representative of the speed of said inside wheel;
• means for generating a reference signal;
• compensating means for adjusting the value of said reference signal in accordance with the steering angle of said inside steerable wheel so that, absent a spin condition at said inside steerable wheel, the output of said compensating means at the 0.degree. steering angle position defines a first signal value and for turns in said one direction from a straight course, the value of the output signal from said compensating means is less than said first signal value when the turning radius of said inside steerable wheel is less than the average turning radius of said vehicle, is equal to said first signal value when the turning radius of said inside steerable wheel is equal to the average turning radius of said vehicle, and is greater than said first signal value when the turning radius of said inside steerable wheel is greater than the average turning radius of said vehicle;
• and
• means for comparing said wheel speed signal and said adjusted reference signal for providing a spin signal.

A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels comprising:

• means for generating a signal representative of the speed of said inside wheel;
• means for generating a reference signal;
• means for comparing said wheel speed signal and said reference signal for providing a spin signal;
• and
• compensating means for adjusting the value of said spin signal in accordance with the steering angle of said inside steerable wheel so that, absent a spin condition at said inside steerable wheel, the output of said compensating means at the 0.degree. steering angle position defines a first signal value and for turns in said one direction from a straight course, the value of the output signal from said compensating means is greater than said first signal value when the turning radius of said inside steerable wheel is less than the average turning radius of said vehicle, is equal to said first signal value when the turning radius of said inside steerable wheel is equal to the average turning radius of said vehicle, and is less than said first signal value when the turning radius of said inside steerable wheel is greater than the average turning radius of said vehicle.

A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels, said vehicle being characterized by a sufficiently small turning radius capability such that for turns in said one direction at progressively greater steering angles of said driven steerable wheels resulting in progressively smaller turning radii, said inside steerable wheel in a first condition has a turning radius less than the average turning radius of said vehicle and hence the speed of said inside steerable wheel is less than the average vehicle speed when no spinning occurs at said inside steerable wheel, thereafter in a second condition has a turning radius equal to the average turning radius of said vehicle and hence the speed of said inside steerable wheel is the same as the average vehicle speed when no spinning occurs at said inside steerable wheel, and still thereafter in a third condition has a turning radius greater than the average turning radius of said vehicle and hence the speed of said inside steerable wheel is greater than the average vehicle speed when no spinning occurs at said inside steerable wheel, said spin control system comprising:

• spin detecting means for said inside steerable wheel including wheel speed sensing means for producing a wheel speed signal representative of the rotational speed of said inside steerable wheel, reference speed generating means for producing a reference speed signal related to the average speed of said vehicle, and comparator means for comparing said wheel speed signal to said reference speed signal and producing a spin signal representative of the difference therebetween;
• and
• compensating means responsive to the steering angle of said inside steerable wheel and operatively associated with said spin detecting means for affecting the value of said spin signal for turns in said one direction in accordance with the steering angle of said inside steerable wheel so that, the effective value of said spin signal is increased during said first condition, unaffected during said second condition, and decreased during said third condition.

For a vehicle having first and second wheels which are driven at least under predetermined conditions and steerable in at least one direction through varying steering angles and which are disposed on laterally opposite sides of said vehicle so that one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels, a spin control system responsive to a signal related to the speed of said one wheel comprising:

• steering angle compensating means having a transfer characteristic for adjusting the value of said signal in accordance with the steering angle of said wheels including an input terminal for receiving said signal and an output terminal for providing said adjusted value signal and means for varying the transfer characteristic of said steering angle compensating means between said input terminal and said output terminal during steering of said wheels in said one direction from a straight course in accordance with variations in said steering angle, such that for a progressively increasing steering angle in said one direction said transfer characteristic has an initial predetermined nonzero value for a zero degree steering angle, thereafter a value progressively approaching zero from said predetermined non-zero value, still thereafter a value progressively approaching said predetermined non-zero value as the steering angle of said wheels correspondingly approaches the condition wherein the turning radius of said one wheel equals the average turning radius of said vehicle, and still further thereafter a value progressively exceeding said non-zero value as the steering angle of said wheels correspondingly surpasses the condition wherein the turning radius of said one wheel equals the average turning radius of said vehicle.