| Patent application number | Description | Published |
| 20080208406 | Nonlinear vehicle yaw/roll/sideslip command interpreter - A command interpreter for a vehicle stability enhancement system that uses a three degree-of-freedom vehicle model employing non-linear suspension and tire characteristics to calculate stability commands. The command interpreter includes a calculator that calculates a front tire lateral force, a calculator that calculates a rear tire lateral force and a command calculator that calculates a yaw-rate command signal, a lateral velocity command signal and a roll angle command signal. The front tire lateral force calculator and the rear tire lateral force calculator calculate the front and rear side-slip angles. The side-slip angles are then converted to a lateral force, where the conversion is selected based on the tire vertical load. The rear tire lateral force is modified for high side-slip angles so that the rear tire lateral force does not become saturated. | 08-28-2008 |
| 20090235724 | IDENTIFICATION OF VEHICLE CG HEIGHT AND MASS FOR ROLL CONTROL - A system and method for determining vehicle CG height and mass in real-time. The method includes selecting a set of vehicle parameters to be considered that includes the vehicle mass and the center of gravity height of the vehicle. Frequency responses are generated using the dynamic model and a plurality of different values for the selected vehicle parameters. During vehicle operation, frequency responses are calculated from a measured vehicle lateral acceleration to a roll angle and/or a roll rate of the vehicle. The generated frequency responses and the calculated frequency responses are compared to determine which of the generated frequency responses more closely matches the calculated frequency responses. The generated frequency responses that most closely match the calculated frequency responses are used to determine the center of gravity height and the vehicle mass from the values for the vehicle parameters. | 09-24-2009 |
| 20090260907 | Autonomous parking strategy based on available parking space - A method is provided for controlling a parallel parking of a vehicle. A distance between the first object and the second object is remotely sensed. The distance is compared to a first predetermined distance and a second predetermined distance. An autonomous first steering strategy maneuver is performed for parking the vehicle between the first object and second object if the distance is greater than the first predetermined distance. The first steering strategy maneuver consists of a first predetermined number of steering cycles for parking the vehicle. An autonomous second steering strategy maneuver is performed for parking the vehicle between the first and second object if the distance is between the first predetermined distance and the second predetermined distance. The second steering strategy maneuver consists of a second predetermined number of steering cycles for parking the vehicle where the second is greater than the first predetermined number of steering cycles. | 10-22-2009 |
| 20090319123 | METHOD AND SYSTEM FOR DETECTING A VIBRATION LEVEL OF A WHEEL WITHIN A RESONATING FREQUENCY RANGE OF A VEHICLE SUSPENSION - A method that detects whether the vibration level of the wheel is within the resonating frequency range by utilizing discrete velocity measurements. The method includes continuously measuring velocity levels of a wheel relative to a sprung mass vehicle component. These measurements are continuously recorded over a period of time. A periodic algorithm is provided, and the periodic algorithm and the velocity measurements are utilized to determine an output value. The output value is utilized to determine whether the vibration level of the wheel is within the resonating frequency range. | 12-24-2009 |
| 20100042293 | Suspension System with Optimized Damper Response for Wide Range of Events - An analytical methodology for the specification of progressive optimal compression damping of a damper of a suspension system to negotiate a multiplicity of severe events, yet provides very acceptable ride quality and handling during routine events. The damping response of the damper is optimized based upon a progressive optimal constrained events damping function derived from a low envelope curve incorporated with a predetermined damper force acting on the wheel center below a predetermined wheel center velocity, u | 02-18-2010 |
| 20100072685 | METHODS AND APPARATUS FOR A SUSPENSION SYSTEM WITH PROGRESSIVE RESISTANCE - A suspension component achieves progressive resistance via a secondary bleed valve, which functions as a support for the primary compression valve at higher displacements, in conjunction with a secondary nonlinear spring element configured to alter the force on the piston at high displacements. | 03-25-2010 |
| 20100082202 | NONLINEAR FREQUENCY DEPENDENT FILTERING FOR VEHICLE RIDE/STABILITY CONTROL - A system and method for facilitating ride and stability control of a vehicle. The system includes a plurality of suspension displacement sensors, with each of the plurality of suspension displacement sensors positioned proximate to a suspension element of the vehicle. The system further includes a nonlinear filter for filtering out a wheel hop frequency from the suspension velocity corresponding to at least one of the plurality of suspension displacement sensors to obtain a resultant suspension velocity. The resultant suspension velocity is used by a control unit to determine the pitch velocity, roll velocity and the heave velocity of the vehicle. | 04-01-2010 |
| 20100131141 | BANK ANGLE ESTIMATION VIA VEHICLE LATERAL VELOCITY WITH FORCE TABLES - A method for road bank detection that has particular application in vehicle stability control systems and vehicle roll-over avoidance systems. The method for detection of a road bank includes obtaining a yaw rate value and a front and/or rear axle force value for a vehicle travelling on the road. It further includes comparing the obtained vehicle yaw rate value with a corresponding predetermined vehicle yaw rate value to obtain a vehicle yaw rate error value and comparing the obtained vehicle front and/or rear axle force value with a corresponding predetermined vehicle front and/or rear axle force value to obtain a vehicle front and/or rear axle force error value, and detecting the road bank based on the obtained vehicle yaw rate error value and the vehicle front and/or rear axle force error value. | 05-27-2010 |
| 20100131144 | KINEMATIC ESTIMATOR FOR VEHICLE LATERAL VELOCITY USING FORCE TABLES - A system and method for estimating vehicle lateral velocity. The method uses a kinematic estimator constructed as a closed-loop Leunberger observer. The kinematic estimator is based on a kinematic relationship between lateral acceleration measurement and rate of change of lateral velocity. The method provides measurement updates based on virtual lateral velocity measurements from front and rear axle lateral force versus axle side-slip angle tables using the lateral acceleration, yaw-rate, longitudinal speed, and steering angle measurements. The method calculates front and rear axle lateral forces from the lateral acceleration and yaw-rate measurements. The method estimates front and rear axle side-slip angles from the calculated front and rear axle lateral forces using the tables. The method calculates multiple virtual lateral velocities from the front and rear side-slip angles and selects one of the virtual lateral velocities that minimizes an error between a measured force and an estimated force as the lateral velocity. | 05-27-2010 |
| 20100131145 | VEHICLE LATERAL VELOCITY AND SURFACE FRICTION ESTIMATION USING FORCE TABLES - A system and method for estimating vehicle lateral velocity and surface coefficient of friction using front and rear axle lateral force versus side-slip angle tables and sensor measurements. The sensor measurements include lateral acceleration, yaw-rate, longitudinal speed and steering angle of the vehicle. The method includes calculating front and rear axle lateral forces and front and rear side-slip angles on the axles of the vehicle. The method also includes identifying two equations from the calculated lateral forces and the vehicle measurements. The method provides tables that identify a relationship between the calculated front and rear axle lateral forces and the front and rear side-slip angles, and determines the vehicle lateral velocity and surface coefficient of friction from the tables. | 05-27-2010 |
| 20100131146 | ESTIMATION OF SURFACE LATERAL COEFFICIENT OF FRICTION - A system and method for estimating surface coefficient of friction in a vehicle system. The method includes providing a kinematics relationship between vehicle yaw-rate, vehicle speed, vehicle steering angle and vehicle front and rear axle side-slip angles that is accurate for all surface coefficient of frictions on which the vehicle may be traveling. The method defines a nonlinear function for the front and rear axle side-slip angles relating to front and rear lateral forces and coefficient of friction, and uses the nonlinear function in the kinematics relationship. The method also provides a linear relationship of the front and rear axle side-slip angles and the front and rear lateral forces using the kinematics relationship. The method determines that the vehicle dynamics have become nonlinear using the linear relationship and then estimates the surface coefficient of friction when the vehicle dynamics are nonlinear. | 05-27-2010 |
| 20100131154 | ESTIMATION OF WHEEL NORMAL FORCE AND VEHICLE VERTICAL ACCELERATION - A method for estimating the normal force at a wheel of a vehicle and the vertical acceleration of the vehicle that has particular application for ride and stability control of the vehicle. The method includes obtaining a suspension displacement value from at least one of a plurality of suspension displacement sensors mounted on the vehicle and estimating a spring force acting on a spring of a suspension element of the vehicle, a damper force acting on a damper of the suspension element of the vehicle, and a force acting at a center of a wheel. The method further includes determining a normal force at the wheel of the vehicle and a vertical acceleration of the vehicle based on the spring force, the damper force and the force at the center of the wheel of the vehicle. | 05-27-2010 |
| 20100131229 | DYNAMIC OBSERVER FOR THE ESTIMATION OF VEHICLE LATERAL VELOCITY - A system and method for estimating vehicle lateral velocity that defines a relationship between front and rear axle lateral forces and front and rear axle side-slip angles. The method includes providing measurements of vehicle yaw-rate, lateral acceleration, longitudinal speed, and steering angle. The method also includes using these measurements to provide a measurement of the front and rear axle forces. The method calculates a front axle lateral velocity and a rear axle lateral velocity, and calculates a front axle side-slip angle based on the rear axle lateral velocity and a rear axle side-slip angle based on the front axle lateral velocity. The method then estimates front and rear axle forces, and selects a virtual lateral velocity that minimizes an error between the estimated and measured lateral axle forces. The method then provides an estimated vehicle lateral velocity using the selected virtual lateral velocity. | 05-27-2010 |
| 20100204866 | Path Planning for Autonomous Parking - A method is provided for determining a vehicle path for autonomously parallel parking a vehicle in a space between a first object and a second object. A distance is remotely sensed between the first object and the second object. A determination is made whether the distance is sufficient to parallel park the vehicle between. A first position to initiate a parallel parking maneuver is determined. A second position within the available parking space corresponding to an end position of the vehicle path is determined. A first arc shaped trajectory of travel is determined between the first position and an intermediate position, and a second arc shaped trajectory of travel is determined between the second position and the intermediate position. The first arc shaped trajectory is complementary to the second arc shaped trajectory for forming a clothoid which provides a smoothed rearward steering maneuver between the first position to the second position. | 08-12-2010 |
| 20100214164 | Longitudinal and Lateral Velocity Estimation Using Single Antenna GPS and Magnetic Compass - A system and method is provided for determining a lateral velocity and a longitudinal velocity of a vehicle equipped. The vehicle includes only one antenna for a GPS receiver and a magnetic compass. A magnitude of a velocity vector of the vehicle is determined. A course angle with respect to a fixed reference using the single antenna GPS receiver is determined. A yaw angle of the vehicle is measured with respect to the fixed reference using a magnetic compass. A side slip angle is calculated as a function of the course angle and the yaw angle. The lateral velocity and longitudinal velocity is determined as a function of the magnitude of the velocity vector and the side slip angle. | 08-26-2010 |
| 20100271236 | FEASIBLE REGION DETERMINATION FOR AUTONOMOUS PARKING - A method is provided for initiating a parking maneuver for parallel parking a vehicle between a first object and a second object. A target parking space is measured. A determination is made whether the measured target parking space is sufficient to allow an autonomous parallel parking maneuver. A region of feasible starting locations is determined to successfully perform the parallel parking maneuver between the first object and the second object if the available parking space is sufficient. A position of a midpoint of a rear axle is determined in relation to the designated region. A determination is made whether the midpoint of the rear axle is within the designated region. A driver of the vehicle is signaled in response to an instantaneous location of the midpoint of the rear axle vehicle being a feasible starting location to initiate the parallel parking maneuver. | 10-28-2010 |
| 20100274450 | METHOD AND APPARATUS FOR PREDICTING VEHICLE ROLLOVER DURING A TRIP-OVER EVENT - A vehicle includes wheels, force sensors adapted for a vertical force and lateral force of each wheel, an onboard device, and a controller. The controller calculates vehicle values using the vertical force and lateral force, compares the values to a corresponding threshold, and automatically deploys the device when each element value does not exceed a corresponding threshold. A method for determining when to deploy an airbag includes measuring a vertical and lateral force at each wheel, and measuring a yaw rate and roll angle. A lateral velocity is calculated using the lateral force, and a lift of each wheel is calculated using the vertical force. The roll angle, roll rate, and stopping time are processed to generate a point on a 3D rollover plane. A rollover energy rate is calculated, and the airbag deploys when the point, rollover energy rate, and lift do not exceed a threshold. | 10-28-2010 |
| 20110087405 | Autonomous Parking Strategy of the Vehicle with Rear Steer - A method includes parallel parking a vehicle between a first object and a second object in response to an available parking distance therebetween. The vehicle includes front steerable wheels and rear steerable wheels. A distance between the first object and the second object is remotely sensed determining whether to apply a one or two cycle parking strategy. An autonomous one cycle parking strategy includes pivoting the front and rear steerable wheels in respective directions for steering the vehicle in a first reverse arcuate path of travel and then cooperatively pivoting the steerable wheels in a counter direction for steering the vehicle in a second reverse arcuate path of travel to a final park position. The autonomous two cycle parking strategy includes performing the one cycle parking maneuver and then changing a transmission gear to a drive gear and pivoting the front and rear steerable wheels in the first direction for moving the vehicle forward to a final park position. | 04-14-2011 |
| 20110093166 | Temperature Compensation Method for an Air Suspension After Engine Shut-Off - A method for temperature compensating an air spring of an air spring suspension of a motor vehicle after engine shut-off. A desired trim height is obtained. At engine shut-off, the ambient temperature is measured and the temperature of air in the air spring determined. After a wait time (for loading/unloading), a start trim height is measured. A predicted trim height is determined for when the air in the air spring is at the ambient temperature. Finally, the volume of the air in the air spring is selectively adjusted so that when the air in the air spring arrives at the ambient temperature, the trim height will be about the desired trim height. | 04-21-2011 |
| 20110125455 | SYSTEM FOR ESTIMATING THE LATERAL VELOCITY OF A VEHICLE - A system and method for estimating vehicle lateral velocity that defines a relationship between front and rear axle lateral forces and front and rear axle side-slip angles. The method includes providing measurements of vehicle yaw-rate, lateral acceleration, longitudinal speed, and steering angle. The method also includes using these measurements to provide a measurement of the front and rear axle forces. The method calculates a front axle lateral velocity and a rear axle lateral velocity, and calculates a front axle side-slip angle based on the rear axle lateral velocity and a rear axle side-slip angle based on the front axle lateral velocity. The method then estimates front and rear axle forces, and selects a virtual lateral velocity that minimizes an error between the estimated and measured lateral axle forces. The method then provides an estimated vehicle lateral velocity using the selected virtual lateral velocity. | 05-26-2011 |