Design, Modeling, and Control of a Single Leg for a Legged-Wheeled Locomotion System with Non-Rigid Joint

This article presents an innovative legged-wheeled system, designed to be applied in a hybrid robotic vehicle’s locomotion system, as its driving member. The proposed system will be capable to combine the advantages of legged and wheeled locomotion systems, having 3DOF connected through a combination of both rigid and non-rigid joints. This configuration provides the vehicle the ability to absorb impacts and selected external disturbances. A state space approach was adopted to control the joints, increasing the system’s stability and adaptability. Throughout this article, the entire design process of this robotic system will be presented, as well as its modeling and control. The proposed system’s design is biologically inspired, having as reference the human leg, resulting in the development of a prototype. The results of the testing process with the proposed prototype are also presented. This system was designed to be modular, low-cost, and to increase the autonomy of typical autonomous legged-wheeled locomotion systems.This work is financed by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia, within project UIDB/50014/2020.info:eu-repo/semantics/publishedVersio

Towards a more robust non-rigid robotic joint

The following paper presents an improved, low cost, non-rigid joint that can be used in both robotic manipulators and leg-based traction robotic systems. This joint is an improvement over the previous one presented by the same authors because it is more robust. The design iterations are presented and the final system has been modeled including some nonlinear blocks. A control architecture is proposed that allows compliant control to be used under adverse conditions or in uncontrolled environments. The presented joint is a cost-effective solution that can be used when normal rigid joints are not suitable.info:eu-repo/semantics/publishedVersio

Modeling and control of a DC motor coupled to a non-rigid joint

Throughout this paper, the model, its parameter estimation and a controller for a solution using a DC motor with a gearbox worm, coupled to a non-rigid joint, will be presented. First, the modeling of a non-linear system based on a DC Motor with Worm Gearbox coupled to a non-rigid joint is presented. The full system was modeled based on the modeling of two sub-systems that compose it—a non-rigid joint configuration and the DC motor with the worm gearbox configuration. Despite the subsystems are interdependent, its modelling can be performed independently trough a carefully chosen set of experiments. Modeling accurately the system is crucial in order to simulate and know the expected performance. The estimation process and the proposed experimental setup are presented. This setup collects data from an absolute encoder, a load cell, voltage and current sensors. The data obtained from these sensors is presented and used to obtaining some physical parameters from both systems. Finally, through an optimization process, the remaining parameters are estimated, thus obtaining a realistic model of the complete system. Finally, the controller setup is presented and the results obtained are also presented.info:eu-repo/semantics/publishedVersio

Data fusion using ultra wideband time-of-flight positioning for mobile robot applications

Self-localization of a robot is one of the most important requirements in mobile robotics. There are several approaches to providing localization data. The Ultra Wide Band Time of Flight provides position information but lacks the angle. Odometry data can be combined by using a data fusion algorithm. This paper addresses the application of data fusion algorithms based on odometry and Ultra Wide Band Time of Flight positioning using a Kalman filter that allows performing the data fusion task which outputs the position and orientation of the robot. The proposed solution, validated in a real developed platform can be applied in service and industrial robots.he authors are grateful to the Foundation for Sci- ence and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021). This work has been supported by NORTE- 01-0247-FEDER-072598 iSafety: Intelligent system for occu- pational safety and well-being in the retail sector. The authors also want to thank CEFET-RJ and FAPERJ.info:eu-repo/semantics/publishedVersio

State estimation of over-sensored systems applied to a low-cost robotic manipulator

There is an increasing demand for robotic manipulators to perform more complex and versatile tasks. In order to fulfill this need, expeditious calibration and estimation techniques are required as a first step for the correct usage of the manipulator. This article aims at finding a subset of these algorithms that could be used in a generic manipulator and should allow for its prompt use. Two models for the representation of the pose of the manipulator are described and used in the state estimation problem. The results of the implementation are tested, and some performance metrics are obtained.info:eu-repo/semantics/publishedVersio

Modeling of an elastic joint: an experimental setup approach

Throughout this paper it is presented a novel elastic joint configuration, being compared with other similar joints found in recent literature. It is presented its modeling, being its estimation process developed offline, based on a proposed experimental setup. This setup enables to monitor and collect data from an absolute encoder and a load cell. Some data obtained from these sensors is then graphically represented, like angle and torque, obtaining some parameters. Finally, through an optimization process, where the error of the angle is minimized, the remaining parameters of the joint are estimated, thus obtaining a realistic model of the system.This work is financed by National Funds through the Portuguese funding agency, FCT- Fundação para a Ciência e a Tecnologia, with in project UIDB/50014/2020info:eu-repo/semantics/publishedVersio

Welcome message

Welcome to the 2023 IEEE International Conference on Autonomous Robot Systems and Competitions (ICARSC). ICARSC is an international scientific meeting in the field of Mobile Robotics financially co-sponsored by the Portuguese Robotics Society, IEEE Portugal Section and IEEE Portugal RAS Chapter and technically co-sponsored by the IEEE Robotics and Automation Society (RAS). ICARSC is currently a recognized international scientific conference in the field of autonomous robotics and competitions. This conference is promoted by Instituto Politécnico de Tomar and the Portuguese Society of Robotics, with the support from Tomar Municipality. Thank you all for participating in this conference. We hope you feel it as a highly productive and sociable event and that you will enjoy your staying in Tomar.info:eu-repo/semantics/publishedVersio

Robot at factory 4.0: an auto-referee proposal based on artificial vision

The robotization and automation of tasks are relevant processes and of great relevance to be considered nowadays. This work aims to turn the manual action of assigning the score for the robotic competition Robot at Factory 4.0 by an automatic referee. Specifically, the aim is to represent the real space in a set of computational information using computer vision, localization and mapping techniques. One of the crucial processes to achieve this goal involved the adaptive calibration of the parameters of a digital camera through visual references and tracking of objects, which resulted in a fully functional, robust and dynamic system that is capable of mapping the competition’s objects accurately and correctly performing the referee’s tasks.This work is financed by National Funds through the Portuguese funding agency, FCT - Funda¸c˜ao para a Ciˆencia e a Tecnologia, within projects LA/P/0063/2020 and POCI-01-0247-FEDER-072638, co-funded by FEDER through COMPETE 2020. Authors acknowledge 5DPO RobotAtFactory team for making their time and robot available to conduct tests. The project that gave rise to these results received the support of a fellowship from “la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028info:eu-repo/semantics/publishedVersio

Spiral inertial microfluidics for size based microalgae separation

The identifcation of toxic microalgae is essential for the sustainable management of activities, such as aquaculture, being also relevant for environmental monitoring and marine research purposes [1]. For these reasons, there is an increasing demand for in situ, reliable, portable, autonomous, low-cost and of easy operation technologies and devices able to detect early signs of potential toxic algal populations within the context of long term monitoring programmes. To this aim, a multisensory platform for in-situ phytoplankton quantifcation and taxonomic identifcation designed for underwater deployment and based on lab-on-chip (LoC) technology has been developed. It combines fow cytometry with optical and electrical measurements. The separation of microalgae based on cell size prior to analysis is key to reduce the complexity and heterogeneous nature of seawater samples while also ofering a degree of distinction between taxonomic groups. This work investigates and develops a simple inertial microfuidic device based on a spiral microchannel that achieves size-based separation of microparticles/ cells. The theoretical principle of their separation was analysed trough numerical simulations and experimental tests were also performed. Using a 5-loop spiral (300 μm width and 100 μm height), 20 μm and 40 μm polystyrene (PS) microparticles were successfully separated for a fow rate of 2000 μl/min, showing its potential for microalgae size-based separation. Furthermore, the simple structure and high throughout makes this technique suitable for integration in LoC devices [2, 3].Peer Reviewe

Design, modeling, and control of an autonomous legged-wheeled hybrid robotic vehicle with non-rigid joints

This paper presents a legged-wheeled hybrid robotic vehicle that uses a combination of rigid and non-rigid joints, allowing it to be more impact-tolerant. The robot has four legs, each one with three degrees of freedom. Each leg has two non-rigid rotational joints with completely passive components for damping and accumulation of kinetic energy, one rigid rotational joint, and a driving wheel. Each leg uses three independent DC motors—one for each joint, as well as a fourth one for driving the wheel. The four legs have the same position configuration, except for the upper hip joint. The vehicle was designed to be modular, low-cost, and its parts to be interchangeable. Beyond this, the vehicle has multiple operation modes, including a low-power mode. Across this article, the design, modeling, and control stages are presented, as well as the communication strategy. A prototype platform was built to serve as a test bed, which is described throughout the article. The mechanical design and applied hardware for each leg have been improved, and these changes are described. The mechanical and hardware structure of the complete robot is also presented, as well as the software and communication approaches. Moreover, a realistic simulation is introduced, along with the obtained results.info:eu-repo/semantics/publishedVersio