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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
3D Axle Alignment
If you look at the position of the wheels with the naked eye, you can sometimes see, even without a wheel alignment gauge, whether the camber is positive or negative. Take a look at the formula-one racing cars on TV and compare the front axle to the rear axle. If their wheel track is the same front and rear, put yourself in a prone position and look along the outside of the respective front wheel, you may be able to ascertain possible differences of less than one degree toe-in or toe-out. Using this method, the exact medial position of the steering can be determined.
Around 1996 the first machines were introduced at trade fairs overseas, at that time of course, there was large scale scepticism. The whole system worked with DOS. The devices today are Windows based computers, very easy to operate with large symbols and are a lot faster. They can concentrate on axle alignment, and if required, they can also be relatively easily linked to a network.
The axel measuring station 'sees with both eyes' which are mounted on the left and right on top in the camera support. The reflectors which are mounted on the wheels must be in a field of view which can be 'seen' by the cameras. Several LEDs are positioned around the camera. If you stand in front of the LEDs, you can notice that they are blinking. Every time it blinks, the diagonal plates on the wheels are photographed by the cameras. The reflector in each wheel has a certain number of points which are repeatedly filmed. Those in the rear are, by the way, larger (figure 2). This relates to the distance between the cameras and the receivers. The 33 points on the reflector are arranged in an exact pattern. It is important that the circles are absolutely round. The distance between the respective circles is also exactly defined. This means that if the wheel or even all four wheels turn while pushing backward and forward, the distance changes between the cameras and the points, and also between the points themselves. An example can be found in a film. Hopefully everybody remembers, 'Gollum' from 'The lord of the rings' who also had points stuck on his body. To make the movements as realistic as possible, an actor, dressed in a black, clinging suit, and of course the points, was filmed while crawling around.. The camera in the 3D measuring station registers every change of distance of each defined point on the reflector several times in the second and calculates with this information. Previously, using the optical method of alignment, one had to adjust a perfect rectangle, the computer does it now by itself, even in the 3D-mode and with almost any vehicle configuration. It composes a diagram of the wheel-geometry of the vehicle and is then immediately ready for measuring.
Once all the measuring plates have been mounted without special adjustment onto the vehicle, the device must ascertain the rotational axis of the wheels. Repeatedly pushing the vehicle back and forth approx. 30 - 40 cm (positioning) helps. This is only an angle of approx. 35 ° on the wheel. By doing this, the front reflectors are recognised by the camera through an additional point.In the course of a controlled measurement, the steering-swivel axis of the steered front wheels are determined, first 10° to each side because of caster and steering axis inclination, then 20° because of the thrust angle. In addition, the maximum steering lock can also be measured. The computer checks not only the left/right lock-stop for each side separately, but also does a plausibility comparison of both sides. 07/08
2001-2015 Copyright programs, texts, animations, pictures: H. Huppertz - E-Mail Translator: Don Leslie - Email: lesdon@t-online.de |
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