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2020 5th International Conference on Robotics and Automation Engineering (ICRAE)最新文献

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Design and Development of a Novel External Pipe Crawling Robot ExPiRo 新型外置管道爬行机器人ExPiRo的设计与研制
Pub Date : 2020-11-20 DOI: 10.1109/ICRAE50850.2020.9310831
I. M. D. C. Jayasundara, A. Mudugamuwa, Han Baokun, K. Perera, Y. Amarasinghe
This paper presents the design approach and development of a novel External Pipeline Robot (EPR) named ExPiRo with the capability of moving on linear segments of cylindrical structures with variable diameters in the range 100 mm to 130 mm. The robot has a passive pipe clutching mechanism created from two parallelogram four-bar linkages. The designed robot can carry payloads up to 2.2 kg. The ExPiRo prototype demonstrated the desired ability to travel on a varying diameter pipe during testing. A control system for position controlling of the robot within the pipeline is also proposed. An ADAMS-MATLAB co-simulation is conducted to evaluate the performance of the proposed control system. The control system demonstrated significant stability in reaching different goal positions.
本文介绍了一种新型的外部管道机器人(EPR) ExPiRo的设计方法和开发,该机器人能够在直径为100 mm至130 mm的圆柱形结构的线性段上移动。该机器人有一个由两个平行四边形四杆机构组成的被动管道抓紧机构。设计的机器人可以携带2.2公斤的有效载荷。在测试过程中,ExPiRo原型机展示了在不同直径的管道上运行的理想能力。提出了一种用于管道内机器人位置控制的控制系统。通过ADAMS-MATLAB联合仿真对所提控制系统的性能进行了评价。控制系统在达到不同目标位置时表现出明显的稳定性。
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引用次数: 0
Development of a Semi-Rigid Tendon Actuated Limb for Robotics Applications 机器人应用半刚性肌腱驱动肢体的研制
Pub Date : 2020-11-20 DOI: 10.1109/ICRAE50850.2020.9310905
Bekarys Nurtay, Tomiris Suranshy, M. Folgheraiter
This paper presents the design and modeling of a lightweight tendon actuated robotic limb. The mechanical structure consists of a sequence of four semi-rigid segments realized in thermoplastic polyurethane material and connected through torsional springs. This allows the limb to keep a straight position without the application of forces and facilitates the control of the limb while performing flexion and extension movements. A static model is presented to predict the tension of the tendons in order to reach a defined orientation. Simulations were conducted in a V-REP Python environment to demonstrate the controllability of the limb while performing simple movements and trajectories.
本文介绍了一种轻型肌腱驱动机器人肢体的设计与建模。机械结构由热塑性聚氨酯材料实现的四个半刚性段组成,并通过扭转弹簧连接。这允许肢体在不施加力的情况下保持笔直的位置,并便于肢体在进行屈伸运动时的控制。提出了一个静态模型来预测肌腱的张力,以达到一个确定的方向。仿真在V-REP Python环境中进行,以演示肢体在执行简单运动和轨迹时的可控性。
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引用次数: 0
Fast CORDIC based Generalized-Voronoi-Diagram Hardware Accelerator for Efficient Robotic Exploration 基于CORDIC的快速广义voronoi图硬件加速器用于机器人的高效探索
Pub Date : 2020-11-20 DOI: 10.1109/ICRAE50850.2020.9310864
Yi Zhan, Zihao Wang, Jiarui Xu, Guoyi Yu, F. An, Wenzheng Chi, Chao Wang
This paper proposes a fast-convergence CO-ordinate Rotation DIgital Computer (CORDIC) based Generalized Voronoi Diagram (GVD) hardware accelerator for efficient robotic path exploration. Owing to the high precision contributed by fast-convergence CORDIC, the proposed GVD hardware accelerator significantly improves the accuracy of the explored paths as compared to the baseline design. Higher precision of the exploration causes shorter trajectory of the robot, which further reduces the power consumption of the entire robot system. Therefore, our design is suitable to the battery-powered small-scale robots. FPGA implementation shows that, the proposed design operating at 12-bit fixed point achieves 54% higher precision of the explored paths and 20% lower power consumption of the robot system than the baseline design, respectively.
提出了一种基于快速收敛坐标旋转数字计算机(CORDIC)的广义Voronoi图(GVD)硬件加速器,用于高效的机器人路径探索。由于快速收敛的CORDIC所带来的高精度,与基线设计相比,所提出的GVD硬件加速器显著提高了探索路径的精度。更高的探测精度使得机器人的轨迹更短,从而进一步降低了整个机器人系统的功耗。因此,我们的设计适用于电池供电的小型机器人。FPGA实现表明,该设计在12位定点工作时,探索路径的精度比基线设计提高了54%,机器人系统功耗比基线设计降低了20%。
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引用次数: 0
Radar Detection Rate Comparison through a Mobile Robot Platform at the ZalaZONE Proving Ground 通过ZalaZONE试验场移动机器人平台的雷达探测率比较
Pub Date : 2020-10-21 DOI: 10.1109/ICRAE50850.2020.9310861
V. Jiménez, C. Schwarzl, Szilárd Josvai
Since an automotive driving vehicle is controlled by Advanced Driver-Assistance Systems (ADAS) / Automated Driving (AD) functions, the selected sensors for the perception process become a key component of the system. Therefore, the necessity of ensuring precise data is crucial. But the correctness of the data is not the only part that has to be ensured, the limitations of the different technologies to accurately sense the reality must be checked for an error-free decision making according to the current scenario. In this context, this publication presents a comparison between two different automotive radars through our self-developed robot mobile platform called SPIDER, and how they can detect different kinds of objects in the tests carried out at the ZalaZONE proving ground.
由于汽车驾驶车辆由高级驾驶辅助系统(ADAS) /自动驾驶(AD)功能控制,因此选择用于感知过程的传感器成为系统的关键组成部分。因此,确保精确数据的必要性至关重要。但数据的正确性并不是唯一需要确保的部分,必须检查不同技术在准确感知现实方面的局限性,以便根据当前场景做出无错误的决策。在这种情况下,本出版物通过我们自主开发的机器人移动平台SPIDER对两种不同的汽车雷达进行了比较,以及它们如何在ZalaZONE试验场进行的测试中检测不同类型的物体。
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引用次数: 0
Trajectory Planning for Automated Driving in Intersection Scenarios Using Driver Models 基于驾驶员模型的交叉口自动驾驶轨迹规划
Pub Date : 2020-10-07 DOI: 10.1109/ICRAE50850.2020.9310863
O. Speidel, Maximilian Graf, Ankita Kaushik, Thanh Phan-Huu, A. Wedel, K. Dietmayer
Efficient trajectory planning for urban intersections is currently one of the most challenging tasks for an Autonomous Vehicle (AV). Courteous behavior towards other traffic participants, the AV’s comfort and its progression in the environment are the key aspects that determine the performance of trajectory planning algorithms. To capture these aspects, we propose a novel trajectory planning framework that ensures social compliance and simultaneously optimizes the AV’s comfort subject to kinematic constraints. The framework combines a local continuous optimization approach and an efficient driver model to ensure fast behavior prediction, maneuver generation and decision making over long horizons. The proposed framework is evaluated in different scenarios to demonstrate its capabilities in terms of the resulting trajectories and runtime.
城市十字路口的有效轨迹规划是当前自动驾驶汽车(AV)最具挑战性的任务之一。对其他交通参与者的礼貌行为,自动驾驶汽车的舒适性及其在环境中的进展是决定轨迹规划算法性能的关键方面。为了捕捉这些方面,我们提出了一种新的轨迹规划框架,以确保社会合规,同时优化自动驾驶汽车在运动学约束下的舒适性。该框架结合了局部连续优化方法和高效的驾驶员模型,以确保快速的行为预测、机动生成和长期决策。提出的框架在不同的场景中进行评估,以证明其在产生的轨迹和运行时方面的能力。
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引用次数: 3
Towards Closing the Sim-to-Real Gap in Collaborative Multi-Robot Deep Reinforcement Learning 缩小协作多机器人深度强化学习中模拟与真实的差距
Pub Date : 2020-08-18 DOI: 10.1109/ICRAE50850.2020.9310796
Wenshuai Zhao, J. P. Queralta, Qingqing Li, Tomi Westerlund
Current research directions in deep reinforcement learning include bridging the simulation-reality gap, improving sample efficiency of experiences in distributed multi-agent reinforcement learning, together with the development of robust methods against adversarial agents in distributed learning, among many others. In this work, we are particularly interested in analyzing how multi-agent reinforcement learning can bridge the gap to reality in distributed multi-robot systems where the operation of the different robots is not necessarily homogeneous. These variations can happen due to sensing mismatches, inherent errors in terms of calibration of the mechanical joints, or simple differences in accuracy. While our results are simulation-based, we introduce the effect of sensing, calibration, and accuracy mismatches in distributed reinforcement learning with proximal policy optimization (PPO). We discuss on how both the different types of perturbances and how the number of agents experiencing those perturbances affect the collaborative learning effort. The simulations are carried out using a Kuka arm model in the Bullet physics engine. This is, to the best of our knowledge, the first work exploring the limitations of PPO in multi-robot systems when considering that different robots might be exposed to different environments where their sensors or actuators have induced errors. With the conclusions of this work, we set the initial point for future work on designing and developing methods to achieve robust reinforcement learning on the presence of real-world perturbances that might differ within a multi-robot system.
当前深度强化学习的研究方向包括弥合模拟与现实的差距,提高分布式多智能体强化学习中经验的样本效率,以及开发分布式学习中对抗智能体的鲁棒方法等。在这项工作中,我们特别感兴趣的是分析多智能体强化学习如何在不同机器人的操作不一定均匀的分布式多机器人系统中弥合与现实的差距。这些变化可能是由于传感不匹配、机械关节校准方面的固有误差或精度上的简单差异而发生的。虽然我们的结果是基于模拟的,但我们引入了传感、校准和精度错配在具有近端策略优化(PPO)的分布式强化学习中的影响。我们讨论了不同类型的扰动以及经历这些扰动的代理数量如何影响协作学习的努力。在Bullet物理引擎中使用Kuka臂模型进行了仿真。据我们所知,这是第一个探索PPO在多机器人系统中的局限性的工作,考虑到不同的机器人可能暴露在不同的环境中,其中它们的传感器或执行器会引起错误。根据这项工作的结论,我们为未来设计和开发方法的工作设定了起点,以便在多机器人系统中可能存在不同的现实世界扰动的情况下实现鲁棒强化学习。
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引用次数: 18
期刊
2020 5th International Conference on Robotics and Automation Engineering (ICRAE)
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