RPS Alignment - Example

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US_Helpdesk
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RPS Alignment - Example

Post by US_Helpdesk » Mon Apr 09, 2012 12:19 pm

An RPS Alignment is used to apply constraints to features in one or more axes. When applied properly six degrees of freedom are constrained / locked in a similar fashion to a 3-2-1 alignment with the added benefit of applying offsets to each feature / constraint.

- In a first axis, three or more RPS constraints must be locked to define an (offset) plane.
- In a second axis, two RPS constraints must be locked to define an (offset) line.
- In a third axis, one RPS constraint must be locked to define the locating point.

This alignment is typical in sheet-metal applications where the Coord System is not local to the part and the primary datum is not a simple plane. i.e. Datum Targets or Net Locators are used for primary Datum, 4-way locator for Secondary Datum and 2-way locator for the Tertiary Datum.

Below is an example of an RPS Alignment in CMM-Manager. In this case only three features are used. Each of these features was measured using Relative Measure so the feature is located position-ally as well as height / depth due to extra sample points being measured.
print.jpg
RPS.jpg
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Murguel
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Re: RPS Alignment - Example

Post by Murguel » Fri Sep 21, 2018 9:01 am

This Alignment is not ideal.

Datum A3 cannot be at same time Datum B because B is the Zero-Point of CAD-Reference-Frame. It should be ideally a Circle but not a Long-Slot. In this Example the correct alignment should be:

A1_B (locked X, Y, Z) 3
A2_C (locked Y, Z) 2
A3 (locked Z) 1

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CrashN8
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Re: RPS Alignment - Example

Post by CrashN8 » Mon Oct 22, 2018 12:14 pm

I think the example is actually correct... Only the feature naming does not match 2D drawing.

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