811 research outputs found
LIPIcs, Volume 251, ITCS 2023, Complete Volume
LIPIcs, Volume 251, ITCS 2023, Complete Volum
Lower limb exoskeleton robot and its cooperative control: A review, trends, and challenges for future research
Effective control of an exoskeleton robot (ER) using a human-robot interface is crucial for assessing the robot's movements and the force they produce to generate efficient control signals. Interestingly, certain surveys were done to show off cutting-edge exoskeleton robots. The review papers that were previously published have not thoroughly examined the control strategy, which is a crucial component of automating exoskeleton systems. As a result, this review focuses on examining the most recent developments and problems associated with exoskeleton control systems, particularly during the last few years (2017â2022). In addition, the trends and challenges of cooperative control, particularly multi-information fusion, are discussed
Collaborative Trolley Transportation System with Autonomous Nonholonomic Robots
Cooperative object transportation using multiple robots has been intensively
studied in the control and robotics literature, but most approaches are either
only applicable to omnidirectional robots or lack a complete navigation and
decision-making framework that operates in real time. This paper presents an
autonomous nonholonomic multi-robot system and an end-to-end hierarchical
autonomy framework for collaborative luggage trolley transportation. This
framework finds kinematic-feasible paths, computes online motion plans, and
provides feedback that enables the multi-robot system to handle long lines of
luggage trolleys and navigate obstacles and pedestrians while dealing with
multiple inherently complex and coupled constraints. We demonstrate the
designed collaborative trolley transportation system through practical
transportation tasks, and the experiment results reveal their effectiveness and
reliability in complex and dynamic environments
Open Innovation and Knowledge Sharing - Towards a sustainable offshore aquaculture
This thesis explores knowledge sharing, open innovation, and skilled relatedness between two industries, the emerging offshore aquaculture industry, and the oil and gas industry. This research placed a significant emphasis on comparing these two industries using the theories presented in chapter two. To gather data for this thesis, a qualitative research method was utilized, which includes semi-structured interviews, a questionnaire, and a literature study.
The desire for sustainable development is a powerful motivator for consumer and company behavior, not to mention government mandates. According to the UN, the world Ěs food output must quadruple by 2050 to feed a rising population. The sea must provide a significant portion of the increasing food output. Aquaculture has been singled out as essential to enhancing the world Ěs food output.
Offshore aquaculture is an innovative method of fish production. Although this method has been researched for a while, we have never been as close to a functioning aquaculture operation at sea as we are now. Compared to the initial fish farming on land or near the shore, offshore aquaculture has presented additional difficulties. The physical environment will be different for offshore aquaculture compared to inshore aquaculture. Despite the distinct physical and climatic circumstances, many of the biological obstacles of offshore aquaculture will still be similar to those of traditional coastal fish farming, including todayâs well-known problems like lice, illness, and fish welfare. Offshore aquaculture developers were obliged to change their approach due to these challenges. Knowledge sharing, skilled relatedness, open innovation and spillovers from the oil and gas industry might all be advantageous for the growing offshore aquaculture industry
Virtual Structures Based Autonomous Formation Flying Control for Small Satellites
Many space organizations have a growing need to fly several small satellites close together in order to collect and correlate data from different satellite sensors. To do this requires teams of engineers monitoring the satellites orbits and planning maneuvers for the satellites every time the satellite leaves its desired trajectory or formation. This task of maintaining the satellites orbits quickly becomes an arduous and expensive feat for satellite operations centers. This research develops and analyzes algorithms that allow satellites to autonomously control their orbit and formation without human intervention. This goal is accomplished by developing and evaluating a decentralized, optimization-based control that can be used for autonomous formation flight of small satellites. To do this, virtual structures, model predictive control, and switching surfaces are used. An optimized guidance trajectory is also develop to reduce fuel usage of the system. The Hill-Clohessy-Wiltshire equations and the D\u27Amico relative orbital elements are used to describe the relative motion of the satellites. And a performance comparison of the L1, L2, and Lâ norms is completed as part of this work. The virtual structure, MPC based framework combined with the switching surfaces enables a scalable method that allows satellites to maneuver safely within their formation, while also minimizing fuel usage
Human centric collaborative workplace: the human robot interaction system perspective
The implementation of smart technologies and physical collaboration with robots in manufacturing can provide competitive advantages in production, performance and quality, as well as improve working conditions for operators. Due to the rapid advancement of smart technologies and robot capabilities, operators face complex task processes, decline in competences due to robots overtaking tasks, and reduced learning opportunities, as the range of tasks that they are asked to perform is narrower. The Industry 5.0 framework introduced, among others, the human-centric workplace, promoting operators wellbeing and use of smart technologies and robots to support them. This new human centric framework enables operators to learn new skills and improve their competencies. However, the need to understand the effects of the workplace changes remain, especially in the case of human robot collaboration, due to the dynamic nature of human robot interaction.
A literature review was performed, initially, to map the effects of workplace changes on operators and their capabilities. Operators need to perform tasks in a complex environment in collaboration with robots, receive information from sensors or other means (e.g. through augmented reality glasses) and decide whether to act upon them. Meanwhile, operators need to maintain their productivity and performance. This affects cognitive load and fatigue, which increases safety risks and probability of human-system error. A model for error probability was formulated and tested in collaborative scenarios, which regards the operators as natural systems in the workplace environment, taking into account their condition based on four macro states; behavioural, mental, physical and psychosocial. A scoping review was then performed to investigate the robot design features effects on operators in the human robot interaction system. Here, the outcomes of robot design features effects on operators were mapped and potential guidelines for design purposes were identified. The results of the scoping review showed that, apart from cognitive load, operators perception on robots reliability and their safety, along with comfort can influence team cohesion and quality in the human robot interaction system.
From the findings of the reviews, an experimental study was designed with the support of the industrial partner. The main hypothesis was that cognitive load, due to collaboration, is correlated with quality of product, process and human work. In this experimental study, participants had to perform two tasks; a collaborative assembly and a secondary manual assembly. Perceived task complexity and cognitive load were measured through questionnaires, and quality was measured through errors participants made during the experiment. Evaluation results showed that while collaboration had positive influence in performing the tasks, cognitive load increased and the temporal factor was the main reason behind the issues participants faced, as it slowed task management and decision making of participants. Potential solutions were identified that can be applied to industrial settings, such as involving participants/operators in the task and workplace design phase, sufficient training with their robot co-worker to learn the task procedures and implement direct communication methods between operator and robot for efficient collaboration
Safe navigation and human-robot interaction in assistant robotic applications
L'abstract è presente nell'allegato / the abstract is in the attachmen
Mechatronic design solution for planar overconstrained cable-driven parallel robot
Cable-driven parallel robots (CDPRs) combine the successful features of parallel manipulators with the benefits of cable transmissions. The payload is divided among light extendable cables, resulting in an energy-efficient system that can achieve
high end-effector acceleration over a huge workspace. A CDPR is formed by a set of actuation units, and a mobile platform, working as an end-effector (EE). The cables, driven by the actuation units, are guided inside the robot workspace using a guidance system and then connected to the mobile platform. The variation of cable lengths is responsible for the EE displacement throughout
the robot workspace. These features result in easily reconfigurable systems where the workspace can be modified by relocating the actuation and guidance units. Nevertheless, the use of CDPRs in industrial environments is still limited, due to the drawbacks of employing flexible cables. Indeed, cables impose unilateral constraints that can only exert tensile forces and, consequently, the EE cannot withstand any arbitrary external action. To enhance the robotâs controllability, CDPRs can be overconstrained by employing a number of cables higher than the degrees of freedom of the EE. This allows cables to pull one against the other and to keep the overall system controllable over a wide range of externally applied loads.
In this thesis, an eight-cable, planar, overconstrained CDPR is designed: the robot has the deployable and reconfigurable features required by the task. In particular, this CDPR has its actuation units installed into the EE mobile platform, and the frame anchor points can be rearranged to obtain a discrete reconfiguration. The cable arrangement, location of anchor points and mechanical design have been studied, by implementing a hybrid optimisation procedure. The genetic algorithm is combined with a local minimum optimiser, maximizing the CDPR volume index and deriving a mechanical design for the prototype
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