EP0996868A4 - Apparatus and method for adjusting wheel alignment camera height - Google Patents

Abstract

Apparatus (30) and method for adjusting the height of wheel alignment cameras (20, 22) includes elevating camera supports for supporting the wheel alignment cameras (20, 22) and adjusting the vertical position of the cameras (20, 22). The wheel alignment cameras (20, 22) provide signals that correspond to the field of view to a processor (34) which provides display signals to a display (36). A camera height control console provides for manual adjusment of camera height.

Description

APPARATUS AND METHOD FOR ADJUSTING WHEEL ALIGNMENT CAMERA HEIGHT

CROSS REFERENCE TO RELATED APPLICATION This application claims priority to U S provisional application Serial No

60/052, 181, filed July 10, 1997, entitled "Camera Lift for the 'Visualiner 3D' Wheel Aligner "

BACKGROUND OF THE INVENTION The present invention relates to a camera lift for use with an optical wheel alignment system and more particularly to a cameia lift system that provides a display of the field of view of wheel alignment cameras and provides means for an operator to adjust the height of wheel alignment cameras

In optical wheel alignment systems, one or more cameras are used to develop signals from targets that connect to the vehicle See U S Patent No 5,724,743, entitled Method and Apparatus for Determining the Alignment of Motor Vehicle Wheels In an optical wheel alignment system, the position of the alignment cameras must remain substantially constant throughout a wheel alignment test Therefore, the cameras and the horizontal beam upon or within which the cameras are mounted (hereinafter "camera bar") remain in a fixed position at a fixed height at most times Movement of the camera bar is avoided To further prevent movement of the camera bar during alignment tests, the camera bar is secured to a stationary object Routine camera bar height adjustments have heretofore been impractical Nevertheless, to perform a wheel alignment test, the images on the wheel targets must be fully within the view of the alignment cameras In prior art optical wheel alignment systems, the height of a vehicle lift is adjusted through a control panel for a hydraulic or other mechanical system until the images on the wheel targets appear to be fully within view of the wheel alignment cameras

In the prior art system descnbed above alignment adjustments are made to a vehicle at a lift height necessitated by the position of the camera bai This provides the mechanic the benefit of observing changes in alignment parameters on a display provided by the optical alignment system as adjustments are made to the vehicle The height required for the alignment system may not, howevei , correspond to the height that is most convenient or desirable for the mechanic or foi pei forming the necessary repairs This inconvenience may have costs, such as inefficient use of the mechanic's time oi less than adequate service

One system for adjusting the height of a wheel alignment camera bar is disclosed in U S Patent No 5,675,515 The camei a elevating mechanism disclosed therein maintains the position of optical targets with respect to the field of view of the cameras as the vehicle lift and vehicle aie elevated However the elevating system disclosed operates undei the contiol of a computei and does not allow the mechanic to control the position of the cameia bar with i espect to the tai et images and does not provide a display so that the mechanic can observe the position of the target images from the perspective of the cameras If the mechanic believes that the alignment parameters provided by the system are in error, no means are provided to verify that the cameras have a target image fully within the field of view In addition, the mechanic cannot readily determine whether a target image or taiget image path is fiee of optical obstacles

SUMMARY OF THE INVENTION Therefore it is an object of this invention to allow a mechanic to adjust the height of a lift in a wheel alignment system to a desned woiking level by providing a device that enables the mechanic to readily adjust and change the height of the camera bar

It is a further object of this invention to provide the mechanic with an indication of the relative height of the camera bar to the images on wheel targets and thus provide information to assist the mechanic when adjusting the height of the camera bar

It is yet another object of this invention to allow the mechanic to adjust the position of the images of wheel taigets with iespect to the field of view of alignment cameras

Another object of this invention is to provide a display of an image in the view of an alignment camera so that a mechanic can l eadily detei mine whether the line of sight from the camera to the image is sufficiently cleai

BRIEF DESCRIPTION OF THE DRAWINGS

Fig 1 is an illustration of a prior art wheel alignment system with a vehicle and vehicle lift

Fig 2 is an illustration of a wheel alignment system that includes the camera lift system of the present invention

Figs 3a-c are illustrations of various displays pi ovided by the camera lift system of the present invention

Fig 4 is an illustration of a vehicle lift and camera lift control console of the present invention

Fig 5 is an illustration of an elevating camera support system of the present invention in a first position

Fig 6 is an illustration of an elevating camera support system of the present invenion in a second position

Fig 7 is an illustration of an elevating camera support of the present invention

Fig 8 is similar to Fig 7, illustrating the components of the elevating camera support

Fig 9 is a block diagram of one embodiment of the present invention

Fig 10 is a block diagram of an alternate embodiment of the present invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An optical wheel alignment system 10 of the prior art is illustrated in Fig 1 A vehicle 1 rests upon a vehicle lift 14 Right side wheel targets 16 and 17 are attached to the right front and rear wheels, respectively, of vehicle 12 Corresponding left side wheel targets, not shown, are also attached to the wheels on the left side of vehicle 12 Camera bar assembly 18 includes a right camera 22 for viewing the wheel targets 16 and 17 on the wheels on the right side of vehicle 10 and a left camera 20 for viewing the wheel targets on the left side, not shown, of vehicle 10 Cameras 20 and 22 optically view images of or on the wheel targets and provide optical signals in response thereto An electronic processor such as a computer 24 receives the optical signals from cameras 20 and 22, processes the signals, calculates alignment parameters and provides alignment data display signals for display on display 26 The displays are preferably orientated so that the mechanic can view the alignment parameters as adjustments are made to the vehicle U S

Patent No 5,724,743 discloses a wheel aligner system of the type just described and is incorporated herein by reference

Referring to Figs 2 and 9, a wheel alignment system 28 including an apparatus for adjusting the height of an alignment camei a of the present invention is disclosed An elevating camera support system 30 includes a camera bar 18 which is shown as extending horizontally in this embodiment but which could be oriented in any direction, provided the camera or cameras are able to view both sides of the vehicle The vertical position of camera bar 18 is adjustable with respect to the elevating camera support system 30 A vehicle lift 14 supports a vehicle 12 having wheel targets, not shown, attached thereto Wheel targets are shown in Fig 1 1 of USPN 5,724,743 Control system 32 provides means to manually adjust the height of vehicle lift 14 and camera bar 18 A processor system 34 receives signals from camera bar 1 8 and provides display signals for display on display 36 Display 36 may be a CRT dιspla\ an LCD a video display, or any other visual displav Piocessoi svstem 14 ma\ be independent of υi , alternatively, associated with the pi ocessor disclosed in U S Patent No 5.675,5 15

Referring to Fig 5, an elevating camei a support system 30 that includes elevating camera supports 48 and 50 is show n Camei a bai 18 includes right and left alignment cameras 22 and 20, respectivel\ Elevating camera support 50 is shown in Figs 7 and 8 Vertical movement of camei a bai 18 is actuated bv an electπcal motoi or other device 56 attached to a chain or other mechanism such as a sci ew oi spring, not shown In the preferred embodiment, the chain is attached to a mounting assembly 58 comprised of a slider 64 and mount 66 Slider 64 is vertically moveable within vertical apertures 60 and 62 formed in vertical support 54 Camera bai 18 is secured to mount 66 Electrical motor 56 is attached to the top of vertical suppoi t ^ and is activated manually by conti ol system

In an alternate embodiment only one elevating camera support supports camera bar 18 In one version of this design, the center of camera bar 18 is attached to mount 66

As shown in Fig 4, control system 32 includes vehicle lift control console 44 and camera height control console 46 In the pi esent embodiment, camera height control console 46 is attached to the side of v ehicle lift contiol console 44 Camera height control console 46 is comprised of a camera height control switch 68, a camera height high button 70 and a camera height low button 72 In the pi efeπ ed embodiment, activation of camera height high button 70 moves camera bar 18 to a height of about 8 feet above ground level Activation of camera height low button 72 moves the camera bar 18 to a height of about 2 feet above ground level Camera height control switch 68 can be manually activated to move the camera bar to any height from the absolute high position of Fig 5 to the absolute low position of Fig. 6 or to any position in between. In a first alternate embodiment, vehicle lift control console 44 is located near the bay doors of the maintenance area and camera height control console 46 is located on the cabinet of computer 34 In a second alternate embodiment, camera height control console 46 is wireless, powered by battery, and communicates via Radio Frequency (RF) or Infrared (IR) signals

Referring to Figs 2 and 3. operation of the wheel alignment system 28 will be described Vehicle 12 is driven onto vehicle lift assembly 14 Wheel targets, not shown, are attached to each wheel of the vehicle Next, the mechanic manually activates vehicle lift control 44 to move vehicle 12 to a desired height The mechanic then decides whether to monitor the field of view of camera 20, camera 22, or both and inputs his selection to computer 34 The mechanic then activates camera height control switch 68 and camera bar 18 moves in the vertical direction while the mechanic monitors the display on display 36 In the present embodiment, display 36 provides a view of the field of view of both right camera 20 and left camera 22 As the camera height approaches the height of the wheel targets, the images on the wheel targets will begin to appear on display 36 By observing the position of the images on the display, the mechanic can determine whether a target is within the field of view of the camera The mechanic continues to adjust the camera height so that the target images are completely within the field of view of the camera and do not overlap If the mechanic believes that further raising or lowering of the vehicle may be required, the target image may be positioned low (or high) in the field of view of the camera

At times, the mechanic may receive alignment data that he may believe to be in error Further, the mechanic may not know the reason for the error The mechanic may check the integrity of the wheel targets and camera by viewing display 36 The display allows the mechanic to identify blockages m the camera optical path and detect dirt accumulation on the surfaces of the targets A display that does not show a complete and clear image of the targets may indicate that the camera height is incorrect, as shown in Figs 3(b) and 3(c), or that there is a problem with the camera assembly or a wheel target A displav showing taiget images within the field of view of the cameras is illustrated in Fig 3(a)

In another embodiment of the present invention, one set of controls is used to operate the vehicle lift and the cameia lift, as shown in Fig 10 In this embodiment, a display is not needed because the height of the cameia bar assembly with respect to the vehicle targets remains fixed Ho evei a displav may be provided to initially verify that the vehicle targets are within the field of view of the cameras

In yet another embodiment, a limited numbei of preferred heights for the vehicle lift are initially designated and marked The field of view display is used to designate corresponding camera lift heights, \\ Inch ai e also mat ked Thereafter, the vehicle lift and camei a lift aie raised directlv to the pi efen ed heights using the vehicle lift control and cameia lift contiol In this embodiment aftei the vehicle and camera lift heights have been marked, the mechanic does not have to i ely upon the display to ensure that the target images are within the field of view of the cameras Rather, the vehicle and camera lifts are raised to discrete, predetermined positions

In still another embodiment the camei a bai is mechanically attached to the vehicle

In a further embodiment the cameia lift has a plurality of opto-electric emitters/sensors, 74, 76, and 78, attached thereto, as shown in Fig 1 1 Vehicle lift 14 has a mirror 80 attach thereto Each opto-electi IC emitter emits a light beam in the horizontal direction Mnror 80 reflects at most one optυ-electnc light beam back to the camera lift to a coi responding opto-electnc sensoi I he opto-electπc sensor that receives the light beam sends a signal to camera lift conti ol dev ice 82 Camera lift control device 82 may be a microcomputer or may operate undei hai dwai e conti ol As illustrated in Fig 12, if opto-electric sensor 76 receives a light beam, control device 82 does not adjust the height of the camera bar. If opto-electric sensor 74 receives a light beam, control device 82 provides a signal to the camera lift assembly 30 to raise the height of the camera bar. If opto-electric sensor 78 receives a light beam, control device 82 provides a signal to the camera lift assembly 30 to lower the height of the camera bar.

An alternative to the previous embodiment includes a pair of linear transducers 84 and 86, as shown in Fig. 1 . Linear transducer 86 provides to control device 82 a signal corresponding to the vertical position of vehicle lift 14 and linear transducer 84 provides to control device 82 a signal corresponding to the vertical position of the camera bar 18. An predetermined offset distance between the vehicle lift and the camera bar is input into control device 82. As the vertical position of vehicle lift 14 is adjusted, linear transducer provides a corresponding signal to control device 82. Control device 82 activates camera lift assembly 30 to lower or raise camera bar 1 8 accordingly. Linear transducer 84 provides a signal corresponding to the adjusted position of the camera bar 18 to the control device 82. Control device 82 deactivates camera lift assembly 30 when the vertical distance between the vehicle lift and camera bar reaches the predetermined offset distance.

Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims

WHAT IS CLAIMED IS

Claim 1 An apparatus for adjusting the height of a wheel alignment camera for viewing wheel alignment targets attached to a vehicle and providing field-of-view signals thereof, comprising at least one elevating camera support for supporting said camera, a drive system associated with said elevating camera support for adjusting the height of said camera, a microprocessor for receiving said field-of-v iew signals and pioviding display signals therefrom a displav toi receiving said displav signals and pi o iding a display of said field-of-view of said wheel alignment camei a a control console in communication with said dnv e system foi selectively and manually activating said drive system

Claim 2 An apparatus foi adjusting the height of a wheel alignment camera for viewing wheel alignment taigets attached to a vehicle comprising elevating camera supports loi supporting said tameia a drive s_\stem associated with said elevating camei a supports for adjusting the height of said camera, a control console in communication with said dnve system foi selectively and manually activating said drive system

Claim 1 An appai atus toi displav mg tield-of-v iew signals provided b_\ a wheel alignment cameia foi v iewing w heel alignment taigets attached to a vehicle comprising a microprocessor for receiving said field-of-view signals and providing display signals therefrom, a display for receiving said display signals and pioviding a display of said field-of-view of said wheel alignment camera

Claim 4 A method toi v ei ticallv aligning the line of sight of a wheel alignment camera having a field of view and supported by at least one camera elevating support, with an image on a wheel target attached to a vehicle supported by a vehicle lift, comprising the steps of: providing a display of said field of view; adjusting the height of said wheel alignment camera on said camera elevating support until said image is completely within said display.

Claim 5. A method for adjusting the height of a wheel alignment camera, supported by a camera boom, relative to an automobile, with wheel targets thereon, on a vehicle lift comprising the steps of: viewing a position of said wheel targets to said wheel alignment camera and developing a display signal indicative of said position, providing said display signal to a display for displaying said indication of said position on a display; observing said display and activating control means for adjusting the height of said wheel alignment camera based upon said display