Authors: H.Y. Shen, Jian Zhong Fu, Zi Chen Chen

Abstract: The proposed Axis-based Look-ahead NURBS Interpolator (ALANI) strictly confines the
component acceleration and jerk at each axis during every interpolating period based on the
mechanics of the machine tools, so that the acceleration and jerk at axes can not exceed the limit in
order to avoid immoderate vibrations and shocks. Contour precision is also strictly guaranteed while
interpolating. The interpolator can trace back and recalculate previous data if necessary after
forwards calculation and verification. And the recalculation algorithm is able to choose optimized
machining parameters to attain high efficiency. The introduction of ALANI and simulation
experiment is present in this paper.

355

Authors: Kun Ren, H.G. Chen, Wen Hua Chen, Jun Pan

Abstract: To guarantee the efficiency and accuracy of machining in high speed machining, a novel vector blending algorithm for velocity smooth link is proposed. Based on efficient acceleration/deceleration technique for a single distance movement, the desired acceleration/deceleration characteristics can be selected. According to acceleration/deceleration characteristics, two different acceleration/deceleration profiles for two corresponding distance movements are constructed respectively. Under the condition of length of movement, highest velocity and direction of motion, two different acceleration/deceleration profiles are blended. On-line implementation results show that the proposed approach makes velocity link smoothly and efficiency and accuracy of machining can be guaranteed.

243

Authors: Zhui Liang Huang, Shu Wen Lin, Dao Ying Jiang

Abstract: In allusion to the problem of data sampling interpolation error which exists in continuous micro-line segments interpolation algorithm with acceleration /deceleration control, this paper proposes a high-precision positioning and speed smooth transition control algorithm for terminal point of micro-line segment. The linear acceleration/deceleration mode was taken as an example to derive a motion control algorithm, which can eliminate the rounding error of the interpolation with fine adjusting the reserved parameters of acceleration /deceleration process when micro-line segment starting point and terminal point velocity are not zero. Simulation analysis and experiments of motion control shows that the algorithm greatly improves the control accuracy of the joint point position of micro-line segments, achieves the continuous smooth transition at the feed speed of the joint point of adjacent line segments and the uniformity of the velocity in specific line segment.

19

Authors: Wen Yu, Li Xu, Shu Li Sun

Abstract: In order to meet the demand of social development, improve the speed and comfort during elevator running process, the elevator speed control system is studied in this article. One new elevator speed control method is put forward. The implementing process of the new method and the design of elevator speed curve are elaborated in detail. The new control method has good utility in improving the running efficiency and the riding comfort for the elevator.

405

Authors: Fang Song, Shuang Hui Hao, Ming Hui Hao

Abstract: The paper presents a novel acceleration/deceleration (acc/dec) control algorithm based on moving-average. The proposed algorithm makes use of the moving-average method to dispose the velocities of all the discrete points obtained by linear acc/dec control algorithm. The acceleration curve is continuous and the speed curve is smooth obtained by this method. Furthermore, the proposed algorithm has easier calculation to achieve. Therefore, CNC simulation system with NC instruction interpretation is established based on this proposed algorithm. The system not only simulates the executive process of NC program files, but also realizes the simulation of speed and acceleration curve, process time and distance with the unit of controlling period. At the same time, the simulation system considers the acc/dec control of feed speed therefore the simulation time equals the real process time. Those will be the value of the instruction to the process of the real machining.

1584