CAJ | 학술논문

为解决作物种植密集,地面障碍与空间障碍并存等非结构化环境因素对温室喷药移动机器人路径跟踪运动控制精度的影响,在建立移动机器人运动学模型的基础上,设计一种基于指数趋近律的滑模变结构控制方法以保证系统对不确定参数及外界干扰的鲁棒性.与此同时,为有效解决滑模控制固有的抖振问题,提出一种加权增益趋近律算法,在该趋近律的积分项中引入负的加权值,可有效避免当系统状态不在滑模切换时的切换增益的增大,使得控制器输出量平滑,并利用 Lyapunov 函数证明了其稳定性,并采用该文所设计的基于加权积分增益趋近律的滑模控制器对喷药移动机器人进行路径跟踪控制.试验结果表明,该算法可以顺利消除横向偏差,使实际运动轨迹平稳跟随理想作业路线,避免在作业区域产生较严重的重喷和漏喷现象,其研究成果为温室作物实施精准喷药提供了依据.
위해결작물충식밀집,지면장애여공간장애병존등비결구화배경인소대온실분약이동궤기인로경근종운동공제정도적영향,재건립이동궤기인운동학모형적기출상,설계일충기우지수추근률적활모변결구공제방법이보증계통대불학정삼수급외계간우적로봉성.여차동시,위유효해결활모공제고유적두진문제,제출일충가권증익추근률산법,재해추근률적적분항중인입부적가권치,가유효피면당계통상태불재활모절환시적절환증익적증대,사득공제기수출량평활,병이용 Lyapunov 함수증명료기은정성,병채용해문소설계적기우가권적분증익추근률적활모공제기대분약이동궤기인진행로경근종공제.시험결과표명,해산법가이순리소제횡향편차,사실제운동궤적평은근수이상작업로선,피면재작업구역산생교엄중적중분화루분현상,기연구성과위온실작물실시정준분약제공료의거.
In order to solve the bad effects of the complex unstructured environment of intensive planting, ground obstacles and spatial disorders on the trajectory tracking control precision of the spraying mobile robot working in greenhouse environment, a sliding mode control scheme was proposed to guarantee system robustness to uncertain parameters and external disturbances. Meanwhile, a novel weighed integral gain reaching law was introduced to solve the inherent chattering problem of sliding mode control, which can be freely controlled with the introduced law. Moreover, the asymptotical stability of the closed loop system was proved by Lyapunov function. The simulation and experimental results showed that adopting the proposed control method, the angular velocity of driving motor for mobile robot can reach the desired value in 0.015 s and the output signal of controller was smooth with the maximal amplitude of 0.02 V. Since the weighed integral gain reaching law included the absolute value of integral for switching function, when switching function approached zero, the gain of switching term converged to zero, while when the state of the system was not on the sliding mode surface, the integral weighted coefficient was negative which can effectively avoid switching gain increasing, smooth control was achieved. The straight-line walking test showed that the mobile robot can successfully eliminate lateral deviation, and can make the actual trajectory near to the desired route in the shortest time. So, it can avoid serious overlap and missing spraying phenomena in the work area. The research results provide a reference for precision spraying the greenhouse crops.