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Measuring XYZ Coordinates of Suspension Model

Measuring XYZ Coordinates of Suspension Model

Measuring XYZ Coordinates of Suspension Model

I am looking to improve a simulation model for one of my test vehicle. I want to put the car on a lift and use a Faro Arm to measure the X,Y,Z components of the static components of the vehicle. My concern is the Faro arm is small and I will have to move it around to gather all the points. This poses the question of what to use as a Point of Origin and how to relate that back to my CarMaker model. I am also concerned about where I should record the point for each component to make sure I am consistent. Any advice on a robust way to do these things would be greatly appreciated.

RE: Measuring XYZ Coordinates of Suspension Model

For convenience the origin is often taken as a point below ground level, in front of the car, and in the middle. This usually puts the centre of the front left wheel at about 1500, -700,500. Obviously we don't measure the origin's location, we use an offset from a reference point on the body.

Small faro arms are very hard to use accurately on car size things. Officially back in the day we were supposed to move the base by spanning, remeasuring the last 3 points we took. Hopefully they've now instrumented the base so it knows where it is.

I'd have thought this was covered in the training.


Greg Locock

New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Measuring XYZ Coordinates of Suspension Model

Our Faro system had software to produce the 'center point' of complex shapes and attachments as needed. You really need high resolution. Make sure you pull the vehicle down to some static position that you are comfortable with, because bushings sag, beams flex, bearings camber, and even spindles need to be located exactly to get the right slopes of movement. THEN the problem is how to build the new configuration because you may find that mm accuracy is needed in an adjustable location.

RE: Measuring XYZ Coordinates of Suspension Model


To establish a point of origin for your Faro Arm measurements, you should choose a fixed reference point on the test vehicle that you can easily measure and locate in your CarMaker model. This could be a specific location on the chassis or a point on a component that is fixed in space.

Once you have established your point of origin, you can then use the Faro Arm to measure the X, Y, and Z coordinates of each component relative to that point. It's important to be consistent with where you record the points for each component, so consider creating a standardized checklist or document that outlines the specific points to measure for each component and the order in which you measure them.

When it comes to relating the Faro Arm measurements back to your CarMaker model, you'll need to transform the coordinates from the Faro Arm's coordinate system to your CarMaker model's coordinate system. This can be done using a transformation matrix, which will enable you to map the measured points onto your CarMaker model.

It's important to note that any errors in your Faro Arm measurements can introduce inaccuracies in your simulation model. To minimize these errors, ensure that you're using the Faro Arm correctly and following best practices for measurement accuracy. It's also a good idea to validate your simulation model against real-world test data to ensure that it's accurately capturing the vehicle's behavior.

I hope this helps! Let me know if you have any further questions.

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