控制工程
控製工程
공제공정
Control Engineering of China
2015年
5期
946-952
,共7页
并联机器人%Lagrange 法%滑模控制%变参趋近率%反正切函数
併聯機器人%Lagrange 法%滑模控製%變參趨近率%反正切函數
병련궤기인%Lagrange 법%활모공제%변삼추근솔%반정절함수
Parallel robot%Lagrange method%Sliding mode control%Variable-parameter reaching law%Arctangent function
并联机构具有时变、强耦合、非线性特性，其动力学模型计算量大、耗时长，难以实现有效的实时控制。针对新型驱动冗余三自由度并联机器人的动力学控制问题，首先，采用 Lagrange 方法进行了完整精确的动力学建模，在此模型的基础上设计了基于指数趋近率的动力学滑模控制器，同时，为消弱滑模控制的抖振、提高控制器性能，引入反正切函数对传统指数趋近率滑模控制进行改进。最后对动力学模型进行仿真分析，并在存在初始误差的情况下进行轨迹跟踪。结果表明，所建模型正确，改进后的滑模控制器程序运行速度大大提高，跟踪快速、精度高，其突出优点是速度抖振极小、输出力输出平稳，能有效消弱系统抖振，较传统指数趋近率滑模控制器性能更好。
併聯機構具有時變、彊耦閤、非線性特性，其動力學模型計算量大、耗時長，難以實現有效的實時控製。針對新型驅動冗餘三自由度併聯機器人的動力學控製問題，首先，採用 Lagrange 方法進行瞭完整精確的動力學建模，在此模型的基礎上設計瞭基于指數趨近率的動力學滑模控製器，同時，為消弱滑模控製的抖振、提高控製器性能，引入反正切函數對傳統指數趨近率滑模控製進行改進。最後對動力學模型進行倣真分析，併在存在初始誤差的情況下進行軌跡跟蹤。結果錶明，所建模型正確，改進後的滑模控製器程序運行速度大大提高，跟蹤快速、精度高，其突齣優點是速度抖振極小、輸齣力輸齣平穩，能有效消弱繫統抖振，較傳統指數趨近率滑模控製器性能更好。
병련궤구구유시변、강우합、비선성특성，기동역학모형계산량대、모시장，난이실현유효적실시공제。침대신형구동용여삼자유도병련궤기인적동역학공제문제，수선，채용 Lagrange 방법진행료완정정학적동역학건모，재차모형적기출상설계료기우지수추근솔적동역학활모공제기，동시，위소약활모공제적두진、제고공제기성능，인입반정절함수대전통지수추근솔활모공제진행개진。최후대동역학모형진행방진분석，병재존재초시오차적정황하진행궤적근종。결과표명，소건모형정학，개진후적활모공제기정서운행속도대대제고，근종쾌속、정도고，기돌출우점시속도두진겁소、수출력수출평은，능유효소약계통두진，교전통지수추근솔활모공제기성능경호。
Parallel mechanism has characteristics such as time-varying, strong coupling and nonlinearity, and its dynamic model has large amount of calculation and is time-consuming. It is difficult to achieve effective real-time control. In this paper, for the dynamic control problem of a new 3-DOF parallel robot with redundant actuation, Lagrange method is used to get an accurate dynamic model. With this model, we design the dynamic sliding mode controller based on the exponential reaching law. At the same time, in order to weaken the chattering of the sliding mode control and improve the controller performance, arctangent function is introduced to improve the traditional sliding mode control based on the exponential reaching law. Finally, the dynamic model is analyzed through simulation and trajectory tracking is conducted in the presence of initial errors. The results show that the proposed model is correct. The running speed of the improved sliding mode controller is greatly improved. Besides, the tracking is fast with high precision. Its advantages lie in the minimal speed chattering and the stable output force. The system chattering is weakened effectively. It has better performance than the traditional sliding mode controller based on the exponential reaching law.
