Z. Irki, Abdelatif Oussar, Mohamed Hamdi, Fatah Seddi
{"title":"A fuzzy UV-disparity based approach for following a leader mobile robot","authors":"Z. Irki, Abdelatif Oussar, Mohamed Hamdi, Fatah Seddi","doi":"10.1109/ICAR.2015.7251451","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251451","url":null,"abstract":"Following a leader is a very important task in the autonomous robot navigation. In order to follow a leader, the follower has to detect the leader, to localize it and to estimate its properties. Several techniques have been used to carry out this task; in particular vision based approaches can be used. In this paper, we describe a stereovision based approach for following a leader. The main idea of this paper assumes that the leader is considered as an obstacle. So, the V-disparity obstacles detection approach is combined with the U-disparity based localization and a fuzzy controller in order to execute all the steps of the leader following task. The described approach was successfully implemented on a Pionneer3AT robot.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125344951","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}
M. Hutter, Philipp Leemann, Stefan Stevšić, Andreas Michel, Dominic Jud, M. Höpflinger, R. Siegwart, R. Figi, Christian Caduff, M. Loher, Stefan Tagmann
{"title":"Towards optimal force distribution for walking excavators","authors":"M. Hutter, Philipp Leemann, Stefan Stevšić, Andreas Michel, Dominic Jud, M. Höpflinger, R. Siegwart, R. Figi, Christian Caduff, M. Loher, Stefan Tagmann","doi":"10.1109/ICAR.2015.7251471","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251471","url":null,"abstract":"This paper presents the successful implementation of force control strategies on a 12 ton walking excavator to optimize the ground reaction force distribution for better stability, less terrain damage and to reduce the operation complexity. Using cleverly arrange standard industrial valve components to separately control in- and out-flow of the hydraulic cylinders, we achieve accurate and fast joint torque control purely based on pressure feedback. On the full system level, we realize an automated force distribution to adjust the center of pressure and to level out the cabin of the machine. While the operator has still full control over the excavator, this assistance system guarantees permanent ground contact and ideal force distribution among the all four wheels independent of the level of the terrain. The proposed method significantly improves operability of the walking excavator in rough terrain.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131140082","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":"Lower limb gait activity recognition using Inertial Measurement Units for rehabilitation robotics","authors":"M. Hamdi, M. Awad, M. Abdelhameed, F. Tolbah","doi":"10.1109/ICAR.2015.7251474","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251474","url":null,"abstract":"In this paper, The authors considered a human lower limb gait activity recognition algorithm, using an IMU sensory network consisting of 4 IMUs distributed to the lower limb. The proposed algorithm depends on Random Forest for classification and a Hybrid Mutual Information and Genetic Algorithm (HMIGA) as a features selection technique. HMIGA selects the most distinguishing features from Discrete Wavelet Coefficient (DWT) features and other statistical and physical (self designed) features. The proposed algorithm is compared with Support Vector Machine (SVM) to classify 5 activities and the results are presented on 6 subjects with 2% average error rate with 1.9% superiority on SVM. Moreover, HMIGA as a feature selector is compared to the traditional feature selectors and DWT as a feature also compared to statistical and physical features, showing their influence on the activity recognition process. Finally, the most important features selected by HMIGA are presented, proving the important role of the shank's sensor on the recognition process, where almost 50% of the selected features are from the shank sensor.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126518244","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":"COACH: Learning continuous actions from COrrective Advice Communicated by Humans","authors":"C. Celemin, J. Ruiz-del-Solar","doi":"10.1109/ICAR.2015.7251514","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251514","url":null,"abstract":"COACH (COrrective Advice Communicated by Humans), a new interactive learning framework that allows non-expert humans to shape a policy through corrective advice, using a binary signal in the action domain of the agent, is proposed. One of the main innovative features of COACH is a mechanism for adaptively adjusting the amount of human feedback that a given action receives, taking into consideration past feedback. The performance of COACH is compared with the one of TAMER (Teaching an Agent Manually via Evaluative Reinforcement), ACTAMER (Actor-Critic TAMER), and an autonomous agent trained using SARSA(?) in two reinforcement learning problems. COACH outperforms all other learning frameworks in the reported experiments. In addition, results show that COACH is able to transfer successfully human knowledge to agents with continuous actions, being a complementary approach to TAMER, which is appropriate for teaching in discrete action domains.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124588589","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":"Enhanced null space control using hierarchical workspace disturbance observer","authors":"M. Sorour, T. Murakami","doi":"10.1109/ICAR.2015.7251426","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251426","url":null,"abstract":"Workspace disturbance observer was developed as further enhancement for the successful joint space observer. In its derivation it was assumed that the null space projector computation could be avoided. However limited performance has been reported for the workspace version. This work shows that the null space projector computation is essential for achieving the expected high performance in workspace. Experimental evaluation revealed the extra advantage of the workspace disturbance observer in terms of higher performance of the null space tasks.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133414380","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":"Deadzone switching based cooperative adaptive cruise control with rear-end collision check","authors":"Feyyaz Emre Sancar, B. Fidan, J. Huissoon","doi":"10.1109/ICAR.2015.7251469","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251469","url":null,"abstract":"In this paper we present a new cooperative adaptive cruise control with rear-end collision check employing deadzone switching techniques. The corresponding control task is to maintain desired spacing between consequent vehicles in a platoon using a decentralized control structure robust to sensor noises, whose magnitudes are assumed to be bounded from above by some known limits. The approach considered here follows a switching control design based on dead-zone using the relative velocity and position of the two closest neighbours.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131004089","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}
Francesco Corucci, M. Calisti, H. Hauser, C. Laschi
{"title":"Evolutionary discovery of self-stabilized dynamic gaits for a soft underwater legged robot","authors":"Francesco Corucci, M. Calisti, H. Hauser, C. Laschi","doi":"10.1109/ICAR.2015.7251477","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251477","url":null,"abstract":"In recent years a number of robotic platforms have been developed, that are capable of robust locomotion in presence of a simple open loop control. Relying on the self-stabilizing properties of their mechanical structure, morphology assumes a crucial role in the design process, that is, however, usually guided by a set of heuristic principles falling under what is commonly known as embodied intelligence. Despite many impressive demonstrations, the result of such a methodology may be sub-optimal, given the dimension of the design space and the complex intertwining of involved dynamical effects. Encouraged by the growing consensus that embodied solutions can indeed be produced by bio-inspired computational techniques in a more automated manner, this work proposes a computer-aided methodology to explore in simulation the design space of an existing robot, by harnessing computational techniques inspired by natural evolution. Although many works exist on the application of evolutionary algorithms in robotics, few of them embrace this design perspective. The idea is to have an evolutionary process suggesting to the human designer a number of interesting robot configurations and embodied behaviors, from whose analysis design hints can be gained to improve the platform. The focus will be on enhancing the locomotion capabilities of a multi-legged, soft, underwater robot. We investigate for the first time the suitability of a recently introduced open-ended evolutionary algorithm (novelty search) for the intended study, and demonstrate its benefits in the comparison with a more conventional genetic algorithm. Results confirm that evolutionary algorithms are indeed capable of producing new, elaborate dynamic gaits, with evolved designs exhibiting several regularities. Possible future directions are also pointed out, in which the passive exploitation of robot's morphological features could bring additional advantages in achieving diverse, robust behaviors.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131085100","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}
Mohamed Lamine Tazir, O. Azouaoui, Mohamed Hazerchi, M. Brahimi
{"title":"Mobile robot path planning for complex dynamic environments","authors":"Mohamed Lamine Tazir, O. Azouaoui, Mohamed Hazerchi, M. Brahimi","doi":"10.1109/ICAR.2015.7251456","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251456","url":null,"abstract":"The last few years, research in the area of path planning for mobile robots has been focusing on dynamic environments. Most of methods proposed in this topic need to re-plan the remaining path of the robot, every time when new information come in which significantly increase the computation time and make real-time implementation of these methods difficult and sometimes impossible. The proposed approach consists of two different modules (static and dynamic) that combine two navigation methods to exploit prior information of global static map and local information coming from sensors. The robot uses global information about his environment, and plans the optimal path using genetic algorithms (GA) combined with Dijkstra algorithm through static obstacles. The dynamic phase is done while the robot is moving. The algorithm is able to avoid a moving obstacle by wait/Accelerate concept (W/A C), or by producing a new optimal local path using Dijkstra algorithm. A particularly new aspect of the work is to use the prior information about the environment for searching a global path efficiently and the incorporation of Dijkstra algorithm in both off-line and online phases, which leads to a significantly computation time reducing, and increases the accuracy of the global trajectory. The introduction of the accelerate action is also a new aspect. The simulation results confirm the efficiency and effectiveness of this approach in complex environments.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132022918","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":"Assessments on the improved modelling for pneumatic artificial muscle actuators","authors":"L. Peternel, B. Ugurlu, J. Babič, J. Morimoto","doi":"10.1109/ICAR.2015.7251430","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251430","url":null,"abstract":"In this paper, we present an analysis regarding the pneumatic air muscle modelling, with a particular emphasis on the exoskeleton robot control. We propose two calibration approaches for obtaining the model identification data. We used the measurement data acquired from the proposed approaches to identify different mathematical models of pneumatic muscles. These models specified the necessary muscle control pressure for the desired muscle force at a given muscle length value. We compared the performance between the different types of models identified by either of the calibration method. The identified model with the lowest validation error was implemented in pneumatic muscle control for an elbow exoskeleton system. As a result, the system exhibited satisfactory torque and position control tasks, adequately validating the proposed approach.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124862186","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":"Finger-like manipulator driven by antagonistic nickel-titanium shape memory alloy actuators","authors":"S. Dilibal, E. Engeberg","doi":"10.1109/ICAR.2015.7251448","DOIUrl":"https://doi.org/10.1109/ICAR.2015.7251448","url":null,"abstract":"Shape memory alloy (SMA) actuators generally have a fast response time when heated. However, the return stroke during cooling can be slow and has been a hindrance to the application of SMA actuators in different areas such as robotic hands. Thus, a novel finger-like antagonistic SMA actuator design is presented in this paper. By using different thermal shape setting processes, one SMA actuator was designed to take a curved shape when heated. This actuator was antagonistically coupled to a different actuator that took a straight shape when heated. Thus, alternately heating each actuator caused the finger-like manipulator to flex and extend rapidly. A comparison study was performed between the novel antagonistic design and a single actuator which showed that the both designs applied approximately the same force with the same velocity when flexing. However, the antagonistic design was able to extend, or open, more rapidly with statistical significance. This was demonstrated for 1.5mm, 1.9mm, and 3.0mm SMA actuator diameters.","PeriodicalId":432004,"journal":{"name":"2015 International Conference on Advanced Robotics (ICAR)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127927517","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}