1,721,004 research outputs found
Machine Learning Algorithm for Robotic Inverse Kinematic Problem
No full textThis work proposes a numerical approach based on a machine learning method associated to neural network back-propagation algorithm to solve the inverse kinematic problem. The algorithm was tested on a redundant manipulator. Obtained numerical results exhibit acceptable accuracy and precision compatible with standard industrial applications
Impact force identification in cobots: A preliminary work
No full textNowadays, cobots have become common in manufacturing industry collaborating with human agents and are predicted to be increasingly part of our lives. Whether it is industrial or service robots, the recent trend is to focus on what has been called human-robot collaboration (HRC). This poses a critical issue regarding the safety of human agents interacting with robot agents. Detecting a collision and executing an appropriate control strategy to reduce impact damages has been proven to be as an effective way to ensure a safe environment for human agents. This paper evaluates an approach for the complete identification of impact action in terms of point of application, intensity, and direction under some illustrative assumptions on robot geometry and system dynamics using only the sensors already present in the robot control system. Simulations have been carried out and their results suggest that the presented approach might be viable for collision detection, isolation, and identification
EWA 2: A Single Size Self-adapting Exoskeleton Without Adjustment for the Upper Limb
No full textThis paper focuses on the design of an upper limb exoskeleton without articular adjustment. It includes a shoulder articulation and explores potential transmission systems applicable to the exoskeletal actuators. A key feature of this exoskeleton is its ability to dynamically adapt between human and exoskeleton joints, thereby mitigating stress on human joints and reducing non-linearity between motor input and human joint output angles. To assess the performance of a 3D printed prototype of the exoskeleton, a dummy with adjustable body segment lengths was fabricated. In vitro experiments utilizing a flexible force sensor confirm that the exoskeleton does not subject the dummy’s joints to overstress
EEG-Based Empathic Safe Cobot
Full text linkAn empathic collaborative robot (cobot) was realized through the transmission of fear from a human agent to a robot agent. Such empathy was induced through an electroencephalographic (EEG) sensor worn by the human agent, thus realizing an empathic safe brain-computer interface (BCI). The empathic safe cobot reacts to the fear and in turn transmits it to the human agent, forming a social circle of empathy and safety. A first randomized, controlled experiment involved two groups of 50 healthy subjects (100 total subjects) to measure the EEG signal in the presence or absence of a frightening event. The second randomized, controlled experiment on two groups of 50 different healthy subjects (100 total subjects) exposed the subjects to comfortable and uncomfortable movements of a collaborative robot (cobot) while the subjects’ EEG signal was acquired. The result was that a spike in the subject’s EEG signal was observed in the presence of uncomfortable movement. The questionnaires were distributed to the subjects, and confirmed the results of the EEG signal measurement. In a controlled laboratory setting, all experiments were found to be statistically significant. In the first experiment, the peak EEG signal measured just after the activating event was greater than the resting EEG signal (p < 10−3). In the second experiment, the peak EEG signal measured just after the uncomfortable movement of the cobot was greater than the EEG signal measured under conditions of comfortable movement of the cobot (p < 10−3). In conclusion, within the isolated and constrained experimental environment, the results were satisfactory
EWA: A Single Size Self-adapting Upper Limb Exoskeleton Without Adjustment
No full textThe work presents an exoskeleton without adjustment (EWA) for the functionality of the upper limb. The main characteristic of the exoskeleton is the self-adapting between the human and exoskeleton joints to avoid overstress in the human joints furthermore it allows a reduced non-linearity between the motor input angle and the human joint output angle. A dummy with variable length of its body segments was realized inserting a flexible force sensor into its joints. In vitro experiments verified that the exoskeleton does not produce overstress in the joints of the dummy
Integrating Clinical Expertise in the Design of Home-Based Smart Rehabilitation Devices for Motor and Cognitive Therapy in Patients with Neurological Disorders
No full textHome-based motor and cognitive rehabilitation are critical for fostering autonomy and reducing long-term healthcare dependency among patients with neurological impairments. Although existing commercial and research-based devices like smart walkers and other mobility aids cater to some patient needs, their design predominantly reflects technical, rather than clinical perspectives, resulting in limited alignment with the specific functional needs of patients with complex neurological deficits. This study aims to bridge this gap by directly involving the domain experts in the definition of the features and functionalities of assistive smart devices tailored to motor assistance and rehabilitation in home environments. Central to this approach is the integration of insights from clinical experts, including physicians, psychologists, physical therapists, and occupational therapists, who bring a nuanced understanding of patient needs within daily life contexts. The main qualitative features that a smart bed and smart walker, integrated into a home-based system for assistance and rehabilitation, should incorporate have been identified through collaborative brainstorming sessions with the experts. These results set up a starting point for these devices’ development
Preliminary study for the development of an autonomous system for emulating mandibular bone drilling
No full textThe use of service robotic systems has had a great expansion. An area in which these systems are used is medical robotics. The introduction of medical robots can limit the number of errors during surgery, where precision is needed. For example, in dental implantology, where a prosthesis is permanently fixed to the bone through drilling and screwing operations, the use of a robotic system can reduce the risk of unlucky events. This preliminary study investigates the feasibility of an autonomous drilling system based on collaborative robots. To evaluate their behaviour 3D printed specimens were developed to emulate the characteristics of cortical and trabecular bone during drilling. The tests show that the samples can generate a thrust force comparable to the one of bone. Finally, the precision and accuracy of the robot were found to be adequate for possible use in operations, subject to an initial evaluation of the system stiffness
Embedded Payload Solutions in UAVs for Medium and Small Package Delivery
Full text linkInvestigations about the feasibility of delivery systems with unmanned aerial vehicles (UAVs) or drones have been recently expanded, owing to the exponential demand for goods to be delivered in the recent years, which has been further increased by the COVID-19 pandemic. UAV delivery can provide new contactless delivery strategies, in addition to applications for medical items, such as blood, medicines, or vaccines. The safe delivery of goods is paramount for such applications, which is facilitated if the payload is embedded in the main drone body. In this paper, we investigate payload solutions for medium and small package delivery (up to 5 kg) with a medium-sized UAV (maximum takeoff of less than 25 kg), focusing on (i) embedded solutions (packaging hosted in the drone fuselage), (ii) compatibility with transportation of medical items, and (iii) user-oriented design (usability and safety). We evaluate the design process for possible payload solutions, from an analysis of the package design (material selection, shape definition, and product industrialization) to package integration with the drone fuselage (possible solutions and comparison of quick-release systems). We present a prototype for an industrialized package, a right prism with an octagonal section made of high-performance double-wall cardboard, and introduce a set of concepts for a quick-release system, which are compared with a set of six functional parameters (mass, realization, accessibility, locking, protection, and resistance). Further analyses are already ongoing, with the aim of integrating monitoring and control capabilities into the package design to assess the condition of the delivered goods during transportation
Design of a 3-DOFs parallel robotic device for miniaturized object machining
No full textThe design of innovative robotic devices reflects the behavior of the modern competitive markets, where the customer’s expectations dramatically increased. Many researches aim to apply innovative solutions to obtain high machining performances and quality of products. This paper deals to present a 3-DOFs parallel robotic device for miniaturized object manipulation and machining. The proposed device has multi-purpose applications and it consists of an actuation system based on preloaded piezoactuators with high dynamics and force, that automatically recover the workpiece distortions or positioning errors due to fixture set-up or machining vibrations. The study presents the main concept of the robotic device, highlighting the main functionalities and components, that impact on the system performance. Moreover, an analytical model is presented and validated using FE analysis, confirming the effectiveness of the adopted approach to control the devic
Role of Reference Frames for a Safe Human–Robot Interaction
Full text linkSafety plays a key role in human–robot interactions in collaborative robot (cobot) applications. This paper provides a general procedure to guarantee safe workstations allowing human operations, robot contributions, the dynamical environment, and time-variant objects in a set of collaborative robotic tasks. The proposed methodology focuses on the contribution and the mapping of reference frames. Multiple reference frame representation agents are defined at the same time by considering egocentric, allocentric, and route-centric perspectives. The agents are processed to provide a minimal and effective assessment of the ongoing human–robot interactions. The proposed formulation is based on the generalization and proper synthesis of multiple cooperating reference frame agents at the same time. Accordingly, it is possible to achieve a real-time assessment of the safety-related implications through the implementation and fast calculation of proper safety-related quantitative indices. This allows us to define and promptly regulate the controlling parameters of the involved cobot without velocity limitations that are recognized as the main disadvantage. A set of experiments has been realized and investigated to demonstrate the feasibility and effectiveness of the research by using a seven-DOF anthropomorphic arm in combination with a psychometric test. The acquired results agree with the current literature in terms of the kinematic, position, and velocity aspects; use measurement methods based on tests provided to the operator; and introduce novel features of work cell arranging, including the use of virtual instrumentation. Finally, the associated analytical–topological treatments have enabled the development of a safe and comfortable measure to the human–robot relation with satisfactory experimental results compared to previous research. Nevertheless, the robot posture, human perception, and learning technologies would have to apply research from multidisciplinary fields such as psychology, gesture, communication, and social sciences in order to be prepared for positioning in real-world applications that offer new challenges for cobot applications
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