Computer-implemented system and method for synthesizing a fixture layout for a part to be manufactured

摘要

Automated fixture layout is approached in two distinct stages. First, the spatial locations of clamping points on the work piece are determined to ensure immobility of the fixtured part under any infinitesimal perturbation. Second, spatial locations are matched against a user-specified library of reconfigurable clamps to synthesize a valid fixture layout or configuration that includes clamps that are accessible and collision free. The spatial locations matching during the second stage can be the same spatial locations chosen in the first stage to ensure immobility, or a different set of spatial locations.

主权项

1. A computer-implemented system for synthesizing a fixture layout for a part to be manufactured, comprising:
at least one computer processor and associated memory; a potential configuration comprising a plurality of locations on the boundary of the part against which to contact a plurality of fixture elements configured to be affixed to a base plate; a determination module to determine a collision free region about each of the locations comprising basis vectors and collision free distances along each of the basis vectors; a part definition module to define a part envelope comprising a geometric representation of a region defined about the boundary of the part; a part identification module to identify a part clearance needed by each of the fixture elements to avoid interference with the part envelope when affixed to the base plate; a catalog comprising a multiplicity of fixture elements specific to a manufacturing facility and configurable to fixture the part; a filter module to filter each candidate fixture element listed in the catalog that exceeds the part clearance in at least one dimension of the candidate fixture element, and to remove from further consideration the filtered candidate fixture elements; a transformation computation module to compute using the at least one computer processor, for each of the candidate fixture elements listed in the catalog and not filtered, a transformation between the part and the base plate, and to align the part with the base plate by the transformation; and an elimination module to eliminate both the candidate fixture elements that are listed in the catalog and not filtered and attachment points of those candidate filter elements to the base plate, which are situated where that fixture element would overlap with another of the remaining fixture elements, the candidate fixture elements and their attachment points remaining after overlap elimination comprising a fixture layout, wherein a plane is defined at a contact point of the plurality of locations and basis vectors X and Y defined by configuration of the attachment points on the base plate, such that the basis vector X comprises an access vector of the candidate fixture element and s comprises spacing of the attachment points on the base plate to determine a transformation with a form closure point (x,y) comprising a position of a location projected onto the base plate, by the expression:If⁢⁢(y⁢mod⁢⁢s)>(s2),thenoffset=s-(y⁢mod⁢⁢s)elseoffset=-(y⁢mod⁢⁢s) where offset comprises a distance by which to shift the part along the Y basis vector and providing an optimized configured fixture layout model that ensures part stability.