关键词： 并联机器人   运动学   动力学   Lagrange方程   位姿  

摘要： 对一种空间3自由度并联机器人(3-RRS并联机器人)进行运动学和动力学分析。此并联机器人的机构由一个动平台和一个静平台通过3个同样的转动副—转动副—球面副的支链组成。完全描述此并联机器人动平台的位置和姿态需要6个变量,即平台上一参考点的3个位移和3个转角。由于此并联机器人拥有2个转动自由度和1个移动自由度,所以,在动平台的6个位姿变量中只有3个变量是独立的。首先,推导此种并联机器人动平台的6个位姿参数之间的约束关系,给出这些变量之间的解析表达式。然后,基于Lagrange方程建立此并联机器人的动力学模型。在此基础上,通过算例分析驱动构件角速度、驱动力/力矩和能耗的变化规律。这些内容为进一步研究此种空间并联机器人的动态性能、机构优化设计和系统控制等都有非常重要的意义。

关键词： Robotic surgery   Laparoscopy   Hysterectomy   Lymph node dissection   Endometrial cancer   Gynecology  

摘要： Objective. To compare outcomes between robotic versus laparoscopic hysterectomy and lymphadenectomy in patients with endometrial cancer. Methods. A cohort study was performed by prospectively identifying all patients with clinical stage I or occult stage 11 endometrial cancer who underwent robotic hysterectomy and lymphadenectomy from 20062008 and retrospectively comparing data using the same surgeons' laparoscopic hysterectomy and lymphadenectomy cases from 1998-2005, prior to our robotic experience. Patient demographics, operative times, complications, conversion rates, pathologic results, and length of stay were analyzed. Results. 181 patients (105 robotic and 76 laparoscopic) met inclusion criteria. There was no significant difference between the two groups in median age, uterine weight, bilateral pelvic or aortic lymph node counts, or complication rates in patients whose surgeries were completed minimally invasively. Despite a higher BMI (34 vs. 29, P<0.001), the estimated blood loss (100 vs. 250 ml, P<0.001), transfusion rate (3% vs. 18%, RR 0.18, 95%CI 0.05-0.64, P=0.002), laparotomy conversion rate (12% vs. 26%, RR 0.47, 95%CI 0.25-0.89, P=0.017), and length of stay (median: I vs. 2 nights, P<0.001) were lower in the robotic patients compared to the laparoscopic cohort. The odds ratio of conversion to laparotomy based on BMI for robotics compared to laparoscopy is 0.20 (95% CI 0.08-0.56, P=0.002). The mean skin to skin time (242 vs. 287 min, P<0.001) and total room time (305 vs. 336 min, P<0.001) was shorter for the robotic cohort. Conclusion. Robotic hysterectomy and lymphadenectomy for endometrial carcinoma can be accomplished in heavier patients and results in shorter operating times and hospital length of stay, a lower transfusion rate, and less frequent conversion to laparotomy when compared to laparoscopic hysterectomy and lymphadenectomy. (C) 2008 Elsevier Inc. All rights reserved.

关键词： Brain-machine interface   Neuroprosthesis   Neuro-robot  

摘要： Many patients suffer from the loss of motor skills, resulting from traumatic brain and spinal cord injuries, stroke, and many other disabling conditions. Thanks to technological advances in measuring and decoding the electrical activity of cortical neurons, brain-machine interfaces (BMI) have become a promising technology that can aid paralyzed individuals. In recent studies on BMI, robotic manipulators have demonstrated their potential as neuroprostheses. Restoring motor skills through robot manipulators controlled by brain signals may improve the quality of life of people with disability. This article reviews current robotic technologies that are relevant to BMI and suggests strategies that could improve the effectiveness of a brain-operated neuroprosthesis through robotics. (C) 2009 Elsevier B.V. All rights reserved.

关键词： ACT-R   Theory of Mind   Embodied cognition   "Like-me" simulation   Cognitive plausibility  

摘要： We present a successful design approach for social robotics based on a computational cognitive architecture and mental simulation. We discuss an approach to a Theory of Mind known as a "like-me" simulation in which the agent uses its own knowledge and capabilities as a model of another agent to predict that agent's actions. We present three examples of a "like-me" mental simulation in a social context implemented in the embodied version of the Adaptive Control of Thought-Rational (ACT-R) cognitive architecture, ACT-R/E (for ACT-R Embodied). Our examples show the efficacy of a simulation approach in modeling perspective taking (identifying another's left or right hand), teamwork (simulating a teammate for better team performance), and dominant-submissive social behavior (primate social experiments). We conclude with a discussion of the cognitive plausibility of this approach and our conclusions.

关键词： Neurosurgery   Robotics   Intraoperative MRI   NeuroArm   Human machine interface  

摘要： Over the past two decades, a number of advances have been made in the application of robotics to neurosurgery. Early robots, able to perform only a few well-defined tasks, have evolved into systems capable of complex tool manipulation. In microsurgery, robotics can now provide the surgeon with various precise and accurate high-fidelity sensory inputs without taking away the surgeon's full control of surgical tasks. A neurosurgical robot incorporating image guidance, rich sensory interface, intraoperative MRI, and microscopy represents the culmination of a logical process in the integration of robotic technology into medicine. This article describes the development and clinical application of neuroArm, a magnetic resonance-compatible robot capable of both stereotaxy and microsurgery.

关键词： classroom   college   robotics   robot   Rapid Plate   instruction   undergraduate   student   student research   competition  

摘要： Students in the Chemistry and Biochemistry Department at Montclair state University have several opportunities to learn about laboratory robotics. A unit on robotics is included in the senior level instrumental analysis class at the end of the spring semester. Students are also able to receive individual instruction on the robotic systems and high-school students have developed automated procedures during summer enrichment programs. An important component of the program is the competition setup between the men and women students of the instrumental analysis class. This keeps student attention focused on the exercises without the need to assign homework. This short article describes the equipment used by the department, provides an overview of how it is used, and contains informal observations made by the author about the student experience. (JALA 2009;14:90-93)

关键词： Dynamics   Kinematics   Parallel robot   Virtual work  

摘要： Recursive matrix relations for kinematics and dynamics of the 3-RRR Agile Wrist spherical parallel robot are established in this paper. The prototype of the robot is a three-degrees-of-freedom mechanism with three identical legs. Controlled by concurrent torques, which are generated by some electric motors, the active elements of the robot have three independent rotations. Knowing the rotation motion of the moving platform, we develop first the inverse kinematical problem and determine the velocities and accelerations. Further, the principle of virtual work is used in the inverse dynamic problem. Matrix equations offer iterative expressions and graphs for the power requirement comparison of each of three actuators in two computational complexities: complete dynamic model and simplified dynamic model. (c) 2008 Elsevier Ltd. All rights reserved.

关键词： Parallel pick-and-place robot   Flexible multibody dynamics   Finite element method   Elasto-dynamics optimization  

摘要： Dynamic modeling and analysis of a 2-DOF translational parallel robot with flexible links for high-speed pick-and-place operation is presented in this paper. Optimization is implemented with the goal to improve the dynamic accuracy of the end-effector at high speed. The governing equations of flexible links within the robot are formulated in the floating reference frame using Euler-Lagrange method, leading to a global FEM model being generated using the KED (Kineto-Elasto-Dynamics) technique. The dynamic characteristics of the robot are then investigated by model analysis. A numerical dynamic index is proposed to identity the range of natural frequency when the robot reaches different configurations. The comparisons are made between the optimized and original designs in terms of dynamic stress and response.

关键词： PRODUCT management   REMOTELY piloted vehicles   RELIABILITY (Engineering)  

摘要： The article reports on the efforts of Frontline Robotics to make its GRUNT autonomous unmanned ground vehicles safer for human security personnel in Rhode Island. The company turned to KVH Industries Inc. and its CNS-5000 fiber-optic, gyro-based continuous navigation system to develop the vehicle. It is expected that the vehicle works in an incredible demanding environment because CNS-5000 offers a range of benefits that help to maintain performance and reliability.