A method of generating an assembly sequence that generates information about assembly steps and an assembly sequence for sequentially assembling a plurality of parts of an assemblable product by using a computer, the method comprising, as processing steps performed by the computer:
- an information acquiring step of extracting, from a three dimensional computer-aided design (3D CAD) model, information about a part attribute, part arrangement, and an adjacency relationship with other parts for each of the plurality of parts;
- a part type classifying step of classifying types of parts from information about the 3D CAD model;
- a characteristic shape detecting step of detecting designated characteristic shapes from the 3D CAD model;
- a part detecting step of detecting a part present in a radial direction of each of the detected characteristic shapes and detecting a part present in an axial direction of the detected part in the 3D CAD model;
- a step of generating a directed graph, in which a node denotes a part and a directed edge denotes a connection precedence relationship between parts and which has a connection precedence relationship, on the basis of results of the detection of the parts;
- a disassembly sequence plan generating step of generating a disassembly unit and a disassembly sequence plan on the basis of the connection precedence relationship;
- an assembly graph generating step of generating an assembly graph, in which a node denotes a part and an edge denotes an adjacency relationship and which represents a relationship between parts, on the basis of adjacency relationship information between parts of the 3D CAD model information;
- an unconnected part detecting step of detecting unconnected parts on the basis of the connection precedence relationship and the assembly graph;
- a work order adding step of adding work contents and work orders to a list of the detected unconnected parts to return to processing in the step of generating the directed graph having the connection precedence relationship;
- and
- an assembly sequence/assembly direction/assembly action generating step of deducing the assembly sequence and an assembly direction for reversely converting a disassemblable direction and a disassembly sequence by generating the disassemblable direction and the disassembly sequence on the basis of the generated disassembly unit, the generated disassembly sequence plan, and the generated assembly graph;
- wherein the unconnected part detecting step detects parts, which have the adjacency relationship but do not have the connection precedence relationship, as unconnected parts on the basis of the assembly graph and the connection precedence relationship created from the 3D CAD model information;
- and
- outputs an unconnected part list including information about parts, which form the unconnected parts, adjacent parts, and the adjacency relationship;
- and
- wherein the unconnected part detecting step detects the unconnected parts to create the unconnected part list;
- acquires characteristic shapes of the unconnected parts;
- groups axial vectors of the characteristic shapes and a vector between centers of the characteristic shapes that have the same direction;
- determines that portions having the characteristic shapes are adjacent portions for each of the groups when a distance between the centers of the characteristic shapes is equal to or smaller than a value of the sum of a half of the length of each of adjacent characteristic shapes and a value of a predetermined clearance;
- and outputs fastening part candidates, which are received in the minimum diameter of the characteristic shape of an adjacent portion, to the unconnected part list.