Iterative Alignment

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Iterative Alignment

Post by cbus_support » Thu Oct 10, 2013 11:36 am

The Datum Alignment tool performs part alignment by a limited number of iterative measurements of specified datum points. This tool ensures the repeatability and accuracy of alignment of various parts with the machine, which usually can be achieved only by using high precision hard fixtures.

Before performing the Datum Alignment, the operator has to provide a close initial part reference frame. The operator can use any available part alignment tool (e.g. CAD alignment or 3-2-1 alignment) to perform this initial part alignment.

Datum Alignment supports two methods: Iterative Bestfit method and Iterative 3-2-1 method. The table below compares the measurement methods and applications of the two methods (the Iterative Bestfit method is recommended for more accurate results).

Iterative Bestfit
Takes 4 points for each one of at least 6 specified datum points to perform iteration.

This method can be used for any types of datum surfaces, sculptural or prismatic, as long as there are at least 6 datum points and they are assigned in such a way that they are physically capable of locating the part in space. No constraints are imposed on the order of the points.

Iterative 3-2-1
Takes a single point for each one of the 6 specified datum points to perform iteration.

This method can only be used for three "almost" mutually orthogonal planes (primary, secondary, and tertiary datum planes), similar to the 3-2-1 Alignment method. The order of these points should be exactly 3-2-1.

NOTE: Using non-orthogonal planes or free-form surfaces may cause slow iteration convergence.

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Joined: Fri Apr 12, 2019 1:24 pm

Re: Iterative Alignment

Post by Torak570 » Thu Jun 06, 2019 2:03 pm

Does anyone have a sample program with this type of alignment so I can just poke around in? I am just looking for something generic. I learn better by seeing and playing with than by watching.

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