Optimizational Design And Experimental Research Of Robot Saddle Shape Variable Groove Cutting

The paper does some research into the cutting of orthogonal saddle-shape pipes on the basement of the study of the development and status of the off-line programming technology. Nowadays, cutting saddle in the shipbuilding industry, manual cutting still exists while the main work has been handed over to the CNC cutting machine. Manual processing, costing a lot of time and having high requirements for workers, is just applying for some simple and small cutting. CNC cutting machine does cutting operation quickly and easily, but there is no space for later upgrade which is negative for the sustainable development and the innovation of science and technology.The paper uses the KUKA robot cutting system for cutting the seat type orthogonal saddle. Some preparation works have been done, for example, fabrication and installation for fixture, schooling gun, establishing the synchronization of positioner and base coordinate system, designing the circuit of solenoid valves for controlling the cutting flame. In this research, we have done the following work and got some conclusions:(1) Establish the orthogonal model and saddle groove angle model. Solve the mathematical expressions of saddle. Get different groove angle and cutting angle on the basis of the plus-minus product of the cosine of the corresponding central angle of main and branch pipes.(2) Using VB language to write offline computing software on VS. Using MATLAB software to simulate results of calculation which is verifying the accuracy of the saddle-shape cutting point and proving the off-line calculation software is feasible.(3) According to the comprehensive analysis of the characteristics and applicable situations of robot motion commands, the mixed instruction of the circle command and the line command is used as the cutting point while the other points picking up PTP command.(4) In this paper, robot oxyacetylene flame cutting has been used in the orthogonal saddle cutting experiment. When the cutting oxygen pressure is 0.6MPa, cutting acetylene pressure of 0.05 MPa and the distance between muzzle and the pipe surface is 6~7mm, the experiment will be carried out. To meet the requirements of production, the main pipe whose outer diameter is 115 mm and wall thickness is 6mm has been cut in the speed of 0.48~0.54m/min by the cutting file atlu1400 with 64 points. To meet the requirements of production, the branch pipe whose outer diameter is 90 mm and wall thickness is 5mm has been cut in the speed of 0.48~0.6m/min by the cutting file atlu14010 with 32 points. It turns out the branch pipe “riding” on the main saddle when they are assembled. The branch cutting touches the surface of the main pipe naturally while the main cutting is coincides with the inner surface of the branch pipe which has verified the accuracy of the off-line calculation program. The target of cutting experiments has been achieved.