Pub Date : 2024-10-21DOI: 10.1109/LRA.2024.3484153
Johan Hatleskog;Kostas Alexis
Degeneracies arising from uninformative geometry are known to deteriorate LiDAR-based localization and mapping. This work introduces a new probabilistic method to detect and mitigate the effect of degeneracies in point-to-plane error minimization. The noise on the Hessian of the point-to-plane optimization problem is characterized by the noise on points and surface normals used in its construction. We exploit this characterization to quantify the probability of a direction being degenerate. The degeneracy-detection procedure is used in a new real-time degeneracy-aware iterative closest point algorithm for LiDAR registration, in which we smoothly attenuate updates in degenerate directions. The method's parameters are selected based on the noise characteristics provided in the LiDAR's datasheet. We validate the approach in four real-world experiments, demonstrating that it outperforms state-of-the-art methods at detecting and mitigating the adverse effects of degeneracies.
{"title":"Probabilistic Degeneracy Detection for Point-to-Plane Error Minimization","authors":"Johan Hatleskog;Kostas Alexis","doi":"10.1109/LRA.2024.3484153","DOIUrl":"https://doi.org/10.1109/LRA.2024.3484153","url":null,"abstract":"Degeneracies arising from uninformative geometry are known to deteriorate LiDAR-based localization and mapping. This work introduces a new probabilistic method to detect and mitigate the effect of degeneracies in point-to-plane error minimization. The noise on the Hessian of the point-to-plane optimization problem is characterized by the noise on points and surface normals used in its construction. We exploit this characterization to quantify the probability of a direction being degenerate. The degeneracy-detection procedure is used in a new real-time degeneracy-aware iterative closest point algorithm for LiDAR registration, in which we smoothly attenuate updates in degenerate directions. The method's parameters are selected based on the noise characteristics provided in the LiDAR's datasheet. We validate the approach in four real-world experiments, demonstrating that it outperforms state-of-the-art methods at detecting and mitigating the adverse effects of degeneracies.","PeriodicalId":13241,"journal":{"name":"IEEE Robotics and Automation Letters","volume":"9 12","pages":"11234-11241"},"PeriodicalIF":4.6,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142598631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1109/LRA.2024.3484131
Yunhai Wang;Lei Yang;Peng Zhou;Jiaming Qi;Liang Lu;Jihong Zhu;Jia Pan
Fabrics present significant challenges to robotic manipulation due to their complex dynamics and infinite degrees of freedom. This letter proposes a non-prehensile approach to aligning a fabric cut piece to a specified target pose, which is a common step for many garment manufacturing tasks. Compared to widely explored prehensile manipulation that grasps and lifts the fabric, the proposed approach uses pushing actions and allows for efficient fabric repositioning with a simpler end-effector. To handle the possible deformation caused by the pushing actions, we introduce the Deformation-aware Rapidly-exploring Random Tree Star (D-RRT*) algorithm that strategically plans the contact poses and actions to slide the fabric to desired configurations by leveraging the friction. Our D-RRT* algorithm enhances fabric manipulation by incorporating deformation-aware action sampling into the path planning process, enabling accurate predictions of non-prehensile actions and efficient navigation through the fabric's configuration space. Extensive simulations and real-world experiments on repositioning fabrics of various shapes and materials demonstrate the effectiveness of the proposed pipeline in achieving stable and efficient manipulation.
{"title":"Efficient Planar Fabric Repositioning: Deformation-Aware RRT* for Non-Prehensile Fabric Manipulation","authors":"Yunhai Wang;Lei Yang;Peng Zhou;Jiaming Qi;Liang Lu;Jihong Zhu;Jia Pan","doi":"10.1109/LRA.2024.3484131","DOIUrl":"https://doi.org/10.1109/LRA.2024.3484131","url":null,"abstract":"Fabrics present significant challenges to robotic manipulation due to their complex dynamics and infinite degrees of freedom. This letter proposes a non-prehensile approach to aligning a fabric cut piece to a specified target pose, which is a common step for many garment manufacturing tasks. Compared to widely explored prehensile manipulation that grasps and lifts the fabric, the proposed approach uses pushing actions and allows for efficient fabric repositioning with a simpler end-effector. To handle the possible deformation caused by the pushing actions, we introduce the Deformation-aware Rapidly-exploring Random Tree Star (D-RRT*) algorithm that strategically plans the contact poses and actions to slide the fabric to desired configurations by leveraging the friction. Our D-RRT* algorithm enhances fabric manipulation by incorporating deformation-aware action sampling into the path planning process, enabling accurate predictions of non-prehensile actions and efficient navigation through the fabric's configuration space. Extensive simulations and real-world experiments on repositioning fabrics of various shapes and materials demonstrate the effectiveness of the proposed pipeline in achieving stable and efficient manipulation.","PeriodicalId":13241,"journal":{"name":"IEEE Robotics and Automation Letters","volume":"9 12","pages":"11258-11265"},"PeriodicalIF":4.6,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10723787","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142598677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adaptive climbing on different surfaces is a great challenge for conventional robots due to a lack of self-sensing capabilities. Inspired by the exceptional sensing ability of feline soles, this study proposes a quadrupedal climbing robot based on self-sensing spiny-claw soles. First, a spiny-claw sole was designed by embedding stainless steel spines into a soft substrate. Next, a tensile strain sensor was designed based on carbon nanotubes and carbonyl iron powder through the squash method and then was integrated into the spiny-claw sole to fabricate the self-sensing sole. Then, a quadrupedal climbing robot was designed using four self-sensing spiny-claw soles. Subsequently, the control strategy of the self-sensing climbing robot was designed. Finally, the climbing performance of the self-sensing robot was experimentally tested. It is demonstrated that the robot can climb on different inclined surfaces with an angle of 0 $^circ$