fixture_solution(m_clamp, clamp_surf3, 25)
fixture_solution(m_clamp, clamp_surf4, 26)
Fixture for additional clamping
fixture_solution(ad_clamp, plane_loc_type, pos1) The plane locating type is horizontal (pos1)
fixture_solution(ad_clamp, plane_loc_face, front) The plane locating face is the front face
fixture_solution(ad_clamp, plane_loc_surf, 1) The plane locating surface is the feature denoted with number 1
fixture_solution(ad_clamp, side_loc_type, p3) The side locating type is p3 (see Fig. 5.)
fixture_solution(ad_clamp, guid_loc_surf, 2) The guiding surface is the feature number 2
fixture_solution(ad_clamp, endw_loc_surf, 32) The endwise locating surface is the feature number 32
fixture_solution(ad_clamp, clamp_type, s13_1) The clamping type is s13_1 (see Fig. 6)
fixture_solution(ad_clamp, clamp_surf1, 11) The clamping surface is the feature with number 11
Operation scheduling
schedule(machining_in_ad_clamp, bottom) The bottom face is machined in additional clamping
schedule(machining_in_main_clamp, back) Back and front faces are machined in main clamping
schedule(machining_in_main_clamp, front)
4.3 Concept of global solution of fixture for additional clamping
The global solution of the fixture for main clamping produces the clamping sequence, as well as the workpiece faces whose machining requires additional clamping. The workpiece position within the machine workspace is selected in such a way to allow machining of those workpiece faces, which are scheduled for machining in additional clamping. The assumed workpiece position has to meet plane locating, side locating, and clamping requirements.
The output from this phase is a conceptual solution for an additional fixture, which completes the process of the production of the conceptual solution of the fixture set.
The system for fixture solution generates an output based on the facts which are grouped into associative triples: fixture_ solution(<object>,<attribute>,<value>), where the object can be one of the following: main clamping fixture (m_clamp) or additional clamping fixture (ad_clamp).
4.4 Test example
Figure 10 shows an example of a typical workpiece. The surfaces (features) of the workpiece are marked with numbers on the drawing. The result of the testing of the expert system is presented in Table 1 in the form of facts. With the help of the post processor, this output in the form of facts can be presented in another form.
References
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