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41.
为了实现精确放疗过程中精确定位和肿瘤位置的精确测量,建立了基于双目视觉的医疗机器人摆位测量系统,并对系统所采用的摄像机标定方法、标记点识别及其三维坐标计算、摆位系统的位置验证等算法进行研究。建立基于双目视觉的医疗机器人摆位测量系统;提出了一种对摄像机采用基于平面棋盘格和立体标定模板相结合的摄像机标定新方法;采用Roberts梯度算子对图像分割的方法,识别标记点中心并计算其三维坐标;通过比较基于双目视觉计算和三维坐标测量仪器测量的各个标记点三维坐标的摆位误差,实现放疗过程中位置验证和精确摆位。实验结果表明:摄像机的标定精度为36.5×10-3 mm和各个标记点的三维坐标平均偏差为δX=0.573mm、δY=0.495mm、δZ=0.430mm,测量方法可获得较高的标定精度和摆位精度,能满足精确放疗对高精度摆位系统的临床需求。 相似文献
42.
为解决并联式自动加注机器人在高精度运动学逆解建模的问题,以并联式自动加注机器人为对象,对其
运动学标定进行研究。采用矢量微分法建立位姿误差模型,对各误差源对动平台末端位姿的影响规律进行分析,寻
找合适的标定位置,并以位姿均方根误差最小为目标函数,使用粒子群算法对神经网络结构进行优化,最后通过仿
真试验对其进行验证。仿真结果表明:该方法能有效提高并联式自动加注机器人的精度,为后续实验应用提供了理
论依据。 相似文献
43.
针对水上救生机器人难以实现快速稳定航行的问题,采用3维反问题设计理论对机器人推进器进行几何设计并对相关参数进行匹配,在合理假设条件下,将喷水推进泵内的有旋流方程进行有效分解获得周向平均流动方程和周期性脉动流动方程。使用速度矩沿流线的分布来控制叶片的载荷,运用计算流体力学对所设计的喷水推进泵进行水力性能校验,结果表明:在毂径比较大等特定条件约束下,喷水推进泵的水力效率达到80.38%,并且在较宽的流量范围内保持高效,叶轮表面压力沿轴向分配合理,没有局部低压区,叶轮推力满足预期性能,验证了设计思路和参数配置的正确性。 相似文献
44.
《Mechatronics》2023
Though constrained by payload and processing, small robots have gained applications in collecting visual information from the scene. Typically these small-size robots do not carry data loggers and send the video information to a hand-held device at a remote location for visual observations. Due to sophisticated processing and control limitations from mechatronics resources, the video captured by the robot is subjected to the effects of unintended motion, which requires digital methods for video stabilization. For a lightweight solution for video stabilization, we avoid use of any external hardware and develop a Singular Value Decomposition (SVD) based digital algorithm that avoids explicit feature tracking and motion estimation during stabilization. The process involves identifying a subspace with minimal dimensions that contains information of intentional motion alone. This work identifies the minimal subspace for video stabilization using the sliding window geometry method for practical implementation. Further, a shape-preserving filter is utilized to remove perturbations induced by the unintended motions, thereby resulting in the reconstruction of the stabilized video sequence. Experimental results on two different small-size robots viz spherical robot and Unmanned Aerial Vehicle (UAV) in indoor and outdoor settings, respectively, show quality outcomes without any change in parameters of the proposed filter design. Performance comparison with existing methods on the quality of stabilized video shows that the proposed stabilization method overcomes the non-availability of features for tracking due to large amplitudes and limited onboard resources. With the proposed video stabilization method, there is a potential for wider applicability of small-size robots in remote visual observations. 相似文献
45.
《Mechatronics》2014,24(2):87-97
In this paper dynamic analysis and robust PID control of fully-constrained cable driven parallel manipulators are studied in detail. Since in this class of manipulators cables should remain in tension for all maneuvers in their workspace, feedback control of such robots becomes more challenging than that of conventional parallel robots. In this paper, structured and unstructured uncertainties in dynamics of the robot are considered and a robust PID controller is proposed for the cable robot. To ensure that all cables remain in tension internal force concept is used in the proposed PID control algorithm. Then, robust stability of the closed-loop system with proposed control algorithm is analyzed through Lyapunov direct method and it is shown that by suitable selection of the PID controller gains, the closed-loop system would be robustly stable. Finally, the effectiveness of the proposed PID algorithm is examined through experiments on a planar cable driven robot and it is shown that the proposed control structure is able to provide suitable performance in practice. 相似文献
46.
汽车车身焊接的智能化与自动化 总被引:1,自引:0,他引:1
主要对焊接机器人的使用实现了车身焊接的智能化与自动化进行研究。首先科学地阐述了弧焊机器人、点焊机器人和激光焊机器人的结构与工作原理以及三种机器人在焊接工作中的特点。接着通过机器人在车身焊接生产线中的应用,集中对实现生产线的柔性化程度和自动化程度;提高装焊专业化、智能化和自动化水平;满足新装焊工艺和技术的要求以及提高生产的智能化和科技的创新化水平进行了科学的分析。 相似文献
47.
Parallel manipulator is a closed-kinematic chain mechanism in which performance of its end effector – moving platform is contributed by its independent actuators. In traditional designs, each elemental actuator has its own controller as well as reference input, and it works independently without gathering information from its neighbors. Consequently, as one of the actuators cannot keep up with the others, the platform performance is easily deteriorated due to the lack of coherence between these actuators. Therefore, the aim of this paper is to design a 3-R planar parallel robot and develop a proper synchronization controller for its tracking control task. Adaptive Network Based Fuzzy Inference System (ANFIS) algorithm was modified and applied as the main strategy of this synchronization controller. The controller is then able to compensate errors between the actuators and enforce them to cooperate harmonically with each other regardless external disturbances caused by the outside environment or geometrical constraints of the closed-loop structure. Simulations and practical experiments on a scaled parallel robot were carried out to evaluate the designed controller. The results showed that by applying the proposed control technique, the working errors of the component actuators converged quickly to zero almost at the same time. As a result, the tracking performance of the common platform was significantly improved in comparison with the performance when applying a non-synchronization controller. The proposed method is effective in controlling systems which require collaborations between the sub-agents. 相似文献
48.
49.
移动机器人轨迹跟踪的模糊PID-P型迭代学习控制 总被引:2,自引:0,他引:2
本文针对移动机器人轨迹跟踪控制问题的研究,提出了一种基于移动机器人运动模型的模糊开闭环PID-P型非线性离散迭代学习控制方法,给出了PID-P型迭代学习的收敛条件及其证明过程,并采用模糊控制的原理整定PID三个学习增益矩阵的参数.该控制方法提高了移动机器人对特定轨迹的重复跟踪能力,具有算法实现简单的特点.实验仿真结果表明,采用模糊开闭环PID-P型迭代学习控制算法对轨迹跟踪是可行有效的. 相似文献
50.
《Mechatronics》2016
In the European manufacturing industry, production batches are decreasing, resulting in an increase in required changeovers. Companies are pushed to respond quickly and cost-efficient to changing markets. One way for Small and Medium sized Enterprises (SMEs) to become more agile, is to incorporate industrial robots in their production processes; larger enterprises already use this versatile piece of equipment for large batch sizes. To do so, a new perspective and approach is required, tailored to dynamic manufacturing systems in which production systems and components can be easily reconfigured, altered, swapped or replaced. A modular system architecture was developed within project SInBot upon which challenges in dynamic cooperation between robots and humans were projected. The developed system uses decentralized control and distributed intelligence, linked through an extensible, flexible, and fault-tolerant communication architecture. The rapidly growing complexity of traditional systems is compared to its decentralized counterpart to illustrate some of the many advantages of this new system architecture. A manufacturing scenario analogue is discussed and the approach to verify the performance of inner-system components, as well as the benefits of this approach. Key challenges that are encountered in implementing the cooperation into the current industrial environments are identified and projected upon the verification system. 相似文献