referring to fig1 reference numeral 10 generally designates a motor vehicle power steering system suitable for implementation of this invention . the steering mechanism 12 is a rack - and - pinion type system and includes a toothed rack ( not shown ) and a pinion gear ( also not shown ) located under gear housing 14 . as the steering wheel 16 is turned , the upper steering shaft 18 , connected to the lower steering shaft 20 through universal joint 22 , turns the pinion gear . rotation of the pinion gear moves the toothed rack that moves tie rods 24 ( only one shown ) that in turn move the steering knuckles 26 ( only one shown ), that turn wheels 28 ( only one shown ). electric power steering assist is provided through the unit generally designated by reference numeral 30 and includes a controller 32 and the electric motor 34 . the controller 32 is powered by a vehicle power supply 36 through line 38 . the controller 32 receives a signal representative of the vehicle velocity on line 40 . steering pinion gear angle is measured through position sensor 42 ( which may be an optical encoding type sensor , variable resistance type sensor or any other suitable type of position sensor ) and fed to the controller 32 through line 44 . as the steering wheel 16 is turned , a torque sensor 43 senses the torque applied to the steering wheel 16 by the vehicle operator . the torque sensor 43 may include a torsion bar ( not shown ) and a variable resistive - type sensor ( also not shown ) that outputs a variable resistance signal to controller 32 through line 46 in relation to the amount of twist on the torsion bar . although this is the preferable torque sensor , any other suitable torque - sensing device used with known signal processing techniques will suffice . in response to the inputs on lines 40 , 44 , and 46 , the controller 32 sends a current command through line 48 to the electric motor 34 . the motor 34 in turn supplies a torque assist to the steering system through a worm 50 and a worm gear 52 , in such a way as to providing the torque assist to the vehicle steering in addition to a driving force exerted by the vehicle operator . referring to fig2 reference numeral 60 generally designates a method for implementing the method for automatic compensation for electric power steering system within the controller 32 . a measure of torque , for instance in newton meters ( nm ) is defined . in addition , a measure of position , for instance in degrees ( deg ) of moving away from the center line either clockwise or counter - clockwise is defined . attention is drawn to the fact that the measure of torque and the measure of position is based on outputs of sensors . torque data flows toward block 64 along line 70 . in the block 64 , the measured torque value is recorded and stored in a memory ( not shown ). it can be appreciated that the memory can be temporary registers in the controller 32 or other form of memories outside the controller 32 such as a random access memory , erasable programmed read only memory , or other suitable forms of memory . the recorded and stored torque values in block 64 then flow along line 72 toward block 66 wherein the recorded and stored torque values are weighted or adjusted according to a friction compensation table or schedule . it is evident that the friction compensation table or schedule is established through the utilization of sensors based , for instance , upon vehicle operating history , certain predetermined formulae , etc . it can be appreciated that a series of compensation settings are determined for a range of possible system hysteresis values . an optimum compensation setting can be determined using various known methods or formulae . after the above adjustment at block 66 , the processed data flows along line 74 to block 68 wherein the incoming adjusted torque values are processed according to a predetermined formula . for example , a difference of the adjusted torque values and the measure of position that is processed in block 62 and transmitted along line 76 is computed and transmitted as output along line 78 . it can be appreciated that data flowing through lines 70 , 72 , 74 , and 76 can be processed according to known methods such that undesirable noise , flowing along data streams or lines 70 , 72 , 74 , and 76 , can be reduced . for example , defining a moving average as a basis for eliminating undesirable data may be used , etc . referring to fig3 reference numeral 80 generally designates a detailed method for implementing the method for automatic compensation for electric power steering of fig2 . a flow chart is depicted . in block 82 , a set of input value including input torque and position values is generated and flows through line 84 . it is noted that the set of input values may be supplied by a set of sensors that sense and measure the set of requisite values . the input values from block 82 are branched into lines 86 and 88 containing essentially the same information . the input values are checked at diamond block 90 for position information . if the position value is greater than a predetermined limit , the information flows through line 92 , and exits the instant flow - chart . if the steering wheel position is not within a programmable limit , the process stops , thus ensuring that the data used to determine a hysteresis estimate is within an appropriate region of a hysteresis loop curve . if the position value is less than a predetermined limit , the information flows through line 94 , the information flows toward diamond block 96 for determination of a current steering wheel turning direction . the filtered data is separated into two groups depending upon current turning direction of the steering wheel . if the current steering wheel turning direction is clockwise , the information flows along line 98 toward block 100 wherein an accumulated clockwise zero crossing data is determined . the information then flows through line 102 toward block 104 for a calculation of hysteresis . complementarily , if the current steering wheel turning direction is counter - clockwise , the information flows along line 106 toward block 108 wherein an accumulated counter - clockwise zero crossing data is determined . a known technique in filtering data may be used at this juncture . for example , a filtering technique using exponentially weighted moving average may be used . the information then flows through line 110 toward block 104 for a calculation of hysteresis . a hysteresis value is determined as a difference between a clockwise zero torque cross point and a counter - clockwise zero torque cross point . the calculated hysteresis information then flows along line 112 into block 114 wherein , together with the input values from block 82 that has branched into line 88 , an output is calculated . the output may be used to adjust or create a compensation by increasing a return - to - center command or increasing an amount of assist to offset the hysteresis . the output then flows out along an output line 116 . referring to fig4 reference numeral 120 generally designates an ideal hysteresis loop . the horizontal co - ordinate denotes steering wheel position measured in degrees as shown . the vertical co - ordinate denotes steering wheel torque measured in newton meters as shown . if no hysteresis exists , lines 122 and 124 collapse into a straight line ( not shown ). because of the existence of wear and other factors , hysteresis occurs . assuming that the wear and other factors are symmetrical , the instant loop curve may be drawn . when a clockwise turning occurs , the line 124 moves toward an upper right - hand direction wherein a zero cross point 126 is determined . symmetrically , when a counter - clockwise turning occurs , the line 122 moves toward a lower left - hand direction wherein a zero cross point 128 is determined . a hysteresis is defined as the difference of the zero cross point 128 and the zero cross point 126 . it will be understood that a person skilled in the art may make modifications to the preferred embodiment shown herein within the scope and intent of the claims . while the present invention has been described as carried out in a specific embodiment thereof , it is not intended to be limited thereby but intended to cover the invention broadly within the scope and spirit of the claims .