Constant force suspension, near constant force suspension, and associated control algorithms
AssigneeBoard of Regents, The University of Texas System
InventorsJoseph H. Beno, Damon A. Weeks, William F. Weldon, Don A. Bresie, Andreas M. Guenin
Life of this patent
Estimating the term…
Abstract
The method and apparatus of the present invention provide constant force suspension and near constant force Suspension and associated control algorithms, all of which may be utilized in vehicle suspension systems. By using the apparatus of the present invention, a vehicle may be isolated from the motion of a wheel as it follows rough terrain, thereby improving ride quality.
Claims28
A constant force or near constant force suspension system, comprising:
- a vehicle body;
- a vehicle wheel;
- an actuator connected between said vehicle wheel and said vehicle body to isolate said vehicle body from surface irregularities by maintaining a substantially constant force on said vehicle body in response to control signals;
- means for determining and tracking a fictitious reference point, said fictitious reference point representing a desired vertical position of said vehicle body, said fictitious reference point stored within a control system, said means coupled to said control system;
- first sensing means for measuring actual vertical position of said vehicle body;
- and
- said control system for developing said control signals, said control signals dependent upon a relative comparison of said fictitious reference point to said actual vertical position, said control system coupled to said actuator.
A method for determining vertical position of a vehicle in motion having a near constant force suspension system, comprising:
- obtaining vertical position data from at least one accelerometer;
- obtaining drift data of said at least one accelerometer by spectrum analysis;
- and
- determining said vertical position from said vertical position data and said drift data.
A method for determining an updated vertical position of a vehicle in motion having a near constant force suspension system, comprising:
- predicting anticipated vertical position data from measured road arm angular displacement, angular velocity, angular acceleration and measured characteristics of an actuator;
- obtaining measured vertical position data from at least one accelerometer;
- obtaining drift data of said at least one accelerometer;
- determining a calculated vertical position from said measured vertical position data and said drift data;
- and
- comparing said anticipated vertical position data to said calculated vertical position data to identify errors in said anticipated vertical position data, thereby developing said updated vertical position of said vehicle.
A method for providing near constant force suspension of a vehicle having a vehicle body and a vehicle wheel and at least one actuator connected between said vehicle body and said vehicle wheel, comprising:
- tracking a fictitious reference point representative of a desired vertical position of said vehicle body;
- determining displacement of said vehicle body relative to said fictitious reference point;
- and
- calculating a modulated torque or force of said at least one actuator using said displacement of said vehicle body, said modulated torque or force sufficient to move said vehicle body to be coincident to said fictitious reference point.
Dependencies are inferred from the claim text.