Apparatus and method for wind-corrected measurement of steering pull on a vehicle
AssigneeIllinois Tool Works Inc.
InventorsJames C. Beebe, Barry D. Cargould
Life of this patent
Estimating the term…
Abstract
Steering pull to which a vehicle is subjected due to tire non-uniformity is measured accurately even in the presence of wind. An anemometer mounted in proximity of and in positionally fixed relation to the vehicle measures the speed and direction of wind apparent to the vehicle. Those measurements are used by a computer to determine a wind correction quantity which is subtracted from the steering pull measured at the steering wheel.
Claims4
An apparatus for measuring, in the presence of wind, the steering pull to which a vehicle is subjected due to non-uniformity of its tires, said apparatus comprising:
- apparent wind measuring means mounted proximate the vehicle and in positionally fixed relation thereto for measuring the speed and direction of wind with respect to the vehicle when the vehicle moves in a direction of travel;
- force measuring means coupled to a steering member of the vehicle for measuring the force which must be exerted on said member in order to prevent substantial change in said direction of said travel;
- and
- computing means operably coupled to said apparent wind measuring means and said force measuring means for generating a steering pull measurement correlated with said force minus a wind correction quantity, said wind correction quantity being determined using a constant value and measurements of said speed and direction of wind made by said apparent wind measuring means.
A method for measuring, in the presence of wind, the steering pull to which a vehicle is subjected due to non-uniformity of its tires, said method comprising the steps of:
- (a) driving the vehicle on its tires over a surface in a direction of travel;
- (b) measuring at a location proximate the vehicle and in positionally fixed relation thereto the direction and speed of the wind apparent to the vehicle;
- (c) measuring the force required to be exerted on a steering member of the vehicle in order to maintain its travel in said direction of travel;
- and
- (d) generating a steering pull measurement correlated with said force minus a wind correction quantity, said wind correction quantity being determined using a constant value and measurements of said direction and speed of said wind apparent to the vehicle.
Dependencies are inferred from the claim text.