{"title":"State Sensing of Spinal Surgical Robot Based on Fusion of Sound and Force Signals","authors":"Meng Li, Xiaozhi Qi, Fengqing Guan, Haiyang Jin, Ying Hu, W. Tian","doi":"10.1109/RCAR52367.2021.9517529","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517529","url":null,"abstract":"Drilling the pedicle is one of the key operations in spinal surgery, which requires the surgeon drilling a hole in the pedicle to implant the screw. Aiming at the operation of the spinal surgery robot, this paper proposes a state sensing method based on multi-source information. The sound and force signals are processed during the drilling process. Because the sound signal changes sensitively and the force signal changes slowly, they should be fused and the appropriate methods are selected at different fusion layers. The interactive multi-model method is performed at the feature layer. It is found that the fusion characteristic curve has better recognition effect than the single signal curve. In the decision-making layer, the support vector machine is used to train and identify the feature quantities of the sound and force signals, achieving a recognition rate of 88%. The effectiveness of the proposed identification method is verified by using multi-parameter experiments.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131866253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Detian Zeng, Lei Sun, Xin Chen, Yunfei Li, Mu Zhu, Xinxiang Gong
{"title":"A Human-Computer Interaction Scheme of Lower-Limb Power-Assist Flexible Robot","authors":"Detian Zeng, Lei Sun, Xin Chen, Yunfei Li, Mu Zhu, Xinxiang Gong","doi":"10.1109/RCAR52367.2021.9517694","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517694","url":null,"abstract":"Wearable flexible walking assist robot can be used to improve the walking state of the senior citizens. This paper proposes to develop an intelligent wearable flexible walking assist robot. It is a human mechanical and electrical system which is worn by subjects and provides walking assistance for users through computer control, perception system, information collection, human-computer interface and other technologies. The device can understand the movement intention of the subjects according to the hip joint angle collected by the gyroscope, which improves the universality of the device for different groups of people. With good human-computer coordination ability, it can effectively assist the senior citizens to walk and play an important role in rehabilitation training, maintain and restore the ability of the elderly to walk out independently, and improve the quality of life of the elderly.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132113197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Data-efficient Deep Reinforcement Learning Method Toward Scaling Continuous Robotic Task with Sparse Rewards","authors":"Junkai Ren, Yichuan Zhang, Yujun Zeng, Yixing Lan","doi":"10.1109/RCAR52367.2021.9517647","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517647","url":null,"abstract":"Dealing with the robotic continuous control problem with sparse rewards is a longstanding challenge in deep reinforcement learning (RL). While existing DRL algorithms have demonstrated great progress in learning policies from visual observations, learning effective policies still requires an impractical number of real-world data samples. Moreover, some robotic tasks are naturally specified with sparse rewards, which makes the precious data inefficient and slows down the learning process, making DRL infeasible. In addition, manually shaping reward functions is a complex work because it needs specific domain knowledge and human intervention. To alleviate the issue, this paper proposes a model-free, off-policy RL approach named TD3MHER, to learn the manipulating policy for continuous robotic tasks with sparse rewards. To be specific, TD3MHER utilizes Twin Delayed Deep Deterministic policy gradient algorithm (TD3) and Model-driven Hindsight Experience Replay (MHER) to achieve highly sample-efficient training property. Because while the agent is learning the policy, TD3MHER could also help it to learn the potation physical model of the robot which is helpful to solve the task, and it does not necessitate any novel robot-environment interactions. The performance of TD3MHER is assessed on a simulated robotic task using a 7-DOF manipulator to compare the proposed technique to a previous DRL algorithm and to verify the usefulness of our method. Results of the experiments on simulated robotic task show that the proposed approach is capable of successfully utilizing previously store samples with sparse rewards, and obtain a faster learning speed.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"58 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133784814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jie Ma, Zhiji Han, Linsen Yang, Gaochen Min, Zhijie Liu, W. He
{"title":"Dynamics modeling of a soft arm under the Cosserat theory","authors":"Jie Ma, Zhiji Han, Linsen Yang, Gaochen Min, Zhijie Liu, W. He","doi":"10.1109/RCAR52367.2021.9517660","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517660","url":null,"abstract":"With the rapid development of robotics, soft robots have received great attention for their superior safety and flexibility. This paper differs from previous kinematic models, and a dynamic model is given based on Cosserat theory. First, the kinematic model of the soft arm is discussed. Further, inspired by rigid robots, Newton inverse kinematics is applied to obtain the Lagrangian dynamic equations of the system. Subsequently, a rope-driven actuator model is provided. Finally, the bending process of the soft arm is provided in $2D, 3D$ and the relationship with the motor tension are discussed in the numerical simulation.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115573383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenming Li, Chaoqun Wang, Jiankun Wang, Yantao Shen, M. Meng
{"title":"Sliding-Window Informed RRT*: A Method for Speeding Up the Optimization and Path Smoothing","authors":"Chenming Li, Chaoqun Wang, Jiankun Wang, Yantao Shen, M. Meng","doi":"10.1109/RCAR52367.2021.9517672","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517672","url":null,"abstract":"Path planning plays a vital role in robot navigation and manipulation, and multiple types of algorithms have been introduced to address this problem. Rapidly-exploring Random Tree (RRT) based algorithms have many advantages over other path planning algorithms. For example, RRT is suitable to solve the path planning problem in high dimensional space and can easily handle robot differential constraints. Informed RRT* is a method that uses the prolate hyper-spheroid to speed up the optimization process, but its efficiency will decrease to the same level as RRT* when the hyper-spheroid covers most of the state space. To overcome this drawback, we further propose a Sliding-Window Informed RRT* (SWIRRT*), which combines the sliding-window thought into the Informed RRT*, taking the advantage of the initial path and make the path optimization much faster. Simulations in 2D space have been carried out to demonstrate that our proposed method can improve the RRT-like algorithm's convergence speed.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"228 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114189550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Visualized Small-size Pipeline Model Building Using Multilink-articulated Wheeled In-pipe Inspection Robot","authors":"Dianzhen Guo, Zhaohan Yuan, Sheng Bao, Jianjun Yuan, Shugen Ma, Liang Du","doi":"10.1109/RCAR52367.2021.9517622","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517622","url":null,"abstract":"In this paper, we use a multilink-articulated wheeled in-pipe robot to develop an industrial solution for the visualized model of the small-size pipeline (less than 200mm) with unknown layout and diameter. We build visualized pipeline model based on small-size inertial measurement unit (IMU) and encoder instead of large-size optical device such as CCD cameras or radar which are expensive and complicated to operate easily. To improve the accuracy of the visualized pipeline model, a multi-sensor data fusion algorithm is developed and the error caused by the gravity factor has been eliminated by using the gradient descent algorithm. The proposed method is experimentally verified in U-Shaped pipeline.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114559100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Linze Wang, Dedong Gao, Jiali Cui, Yan Zhao, Juntao Zhang
{"title":"Research on Mechanical Properties of Bevel-Tip Needle Based on Image Guidance","authors":"Linze Wang, Dedong Gao, Jiali Cui, Yan Zhao, Juntao Zhang","doi":"10.1109/RCAR52367.2021.9517682","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517682","url":null,"abstract":"The flexible needle is a minimally invasive medical device mainly used for human biopsy. The insertion operation has a small wound, which is conducive to the rehabilitation of patients and has a good application prospect. However, the force of the flexibility on the tissue is not certain, which seriously affects the doctor's judgment of the injury caused by the needle insert to the patient. In this paper, the mechanical properties of the flexible needle are studied by image analysis, the mechanical model between the needle holder and the force sensor is established, and the force of the needle holder is calculated by the force sensor data. Based on the cantilever beam model, the cutting force of the needle tip to the soft tissue and the friction force of the needle body are analyzed by using the force of the needle holder. The mechanical properties of flexible needles and the damage to tissues caused by needle insertion have been studied. Finally, the deflection of the needle body is calculated using the experimental force data, which are compared with the analysis by the image processing system. The results show that the cantilever beam model can predict the force of the needle body more accurately, and then predict the insertion trajectory.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115001334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research on SLAM of Corridor Environment Based on Multi-Sensor","authors":"Fei Wang, H. Shao, Q. Zhao, Zhiquan Feng","doi":"10.1109/RCAR52367.2021.9517540","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517540","url":null,"abstract":"In view of the problems of large positioning deviation and map offset in the use of laser and vision sensors to construct maps in the corridor environment, the current stage of multi-sensor fusion SLAM algorithm is researched. Improving a SLAM algorithm based on weighted observation fusion EKF, fusing lidar, depth camera and IMU sensor information, and adding a closed-loop detection verification mechanism at the back of the SLAM algorithm. In order to verify the effectiveness of the algorithm, 16 feature points are selected to perform error analysis. The average map update time is reduced by 0.29s, the average relative error is reduced by 1.277%, and the maximum relative error is reduced from 3.130% to 0.673%.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115276838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Autonomous mobile robot navigation in uncertain dynamic environments based on deep reinforcement learning","authors":"Zhangfan Lu, Ran Huang","doi":"10.1109/RCAR52367.2021.9517635","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517635","url":null,"abstract":"In this paper, we study autonomous end-to-end navigation for wheeled robots based on deep reinforcement learning (DRL) in an unknown environment without a priori map. The DRL network is mainly based on deep deterministic policy gradient algorithm together with long short-term memory. The input for the network is the data from a 2D lidar as well as the relative position to the target point, while the outputs are the linear velocity and angular velocity that actuate the robot. A novel reward function is proposed to avoid the collision with dynamic obstacles and to generate a smooth trajectory for the robot. The network is trained without supervision in an unknown dynamic environment, the random Gaussian noise is added to the input data of long short-term memory to avoid local optimum. Besides, different unstructured environments are also considered in the training to increase the robustness of the developed network. Experiments performed on public dataset have showed that the developed network makes the robot navigate in unstructured environments safely and outperform several DRL methods.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125363774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TactCapsNet: Tactile Capsule Network for Object Hardness Recognition","authors":"Senlin Fang, Tingting Mi, Zhenning Zhou, Chaoxiang Ye, Chengliang Liu, Hancheng Wu, Zhengkun Yi, Xinyu Wu","doi":"10.1109/RCAR52367.2021.9517551","DOIUrl":"https://doi.org/10.1109/RCAR52367.2021.9517551","url":null,"abstract":"Hardness is one of the most essential tactile clues for robots to recognize objects. However, methods for robots to recognize hardness are limited. In this paper, based on the Capsule Network (CapsNet), we propose a novel tactile capsule network (TactCapsNet) for object hardness recognition. Specifically, we collect a tactile dataset on the silicone samples with three different shapes, and the silicone samples of each shape have thirteen hardness levels ranging from 0A (Shore A scale) to 60A at 5A intervals. Furthermore, we construct the tactile image as the input of the CapsNet to make full use of the spatio-temporal information of the tactile hardness dataset. The experimental results prove that the proposed approach achieves higher accuracy and quadratic weighted kappa (QWK) than support vector machine (SVM), long short-term memory (LSTM), convolutional neural network (CNN), and CapsNet.","PeriodicalId":232892,"journal":{"name":"2021 IEEE International Conference on Real-time Computing and Robotics (RCAR)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126548183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}