The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this work, we present a bio-inspired fin prototype as a propulsion system for a submarine robot. We explain the rajiform locomotion, which is intended to be imitated with the movements of the fin. It is also explained how the undulations on the fin allow it to have different behaviors, thus generating thrust in different directions, which in turn generates several types of motion for the fin. Our...
This paper proposes an online compensation method of gravity and friction by least squares method (LSM) for robots implementing haptics. In order to expand the range of tasks using the robot such as telepresence robot, implementing haptics technology is essential. However, with higher gear ratio motors, the friction lowers the quality of the haptic transmission. In order to comfortably control the...
Aiming at the security problem of cooperative robots, this paper presents a low cost collision detection algorithm without torque sensors. In this method, the collision can be detected with the sampling torque and the dynamic model. First, the relationship between the output torque and the motion state of the rotating joint of the robot is established according to the Newton Euler method. For the...
This document introduces an air-land robotic platform called Hexapodopter, capable of ground locomotion and vertical take-off and landing (VTOL). For walking, each of the limbs feature three degrees of freedom (DoF); for flying, the thrust is provided by a set of motors and propellers mounted on every limb. Due to its mechanical design, the Hexapodopter can reconfigure the thrust vectors of propellers...
This paper shows the design of a 2-DOF exoskeleton simulating ball and socket joint, for use on the human shoulder. This design is based on the natural movement of the human shoulder wich has a ball and socket joint. In addition, will be a dynamic and control analysis.
Welding is an important operation in manufacturing processes and it can represent a highly relevant amount of production costs, depending on material workpieces and required weld quantity. In mechanised and robotised welding processes, robot's travel velocity is an important parameter, which requires a proper regulation to obtain a good quality for weld beam. Then, in this work, a nonlinear model...
The design employs direct drive torque motor to achieve a robot single joint with active compliance based on the impedance model. In order to maximize the torque density, transmission transparency and backdrivability, the joint employs a quasi-direct actuator that a single-stage planetary gear is mounted on the motor's rotor. When robot interacts with environments, it's inevitable to change the stiffness...
This paper deals with the improvement of autonomous underwater robot propulsion systems. These need upgrades to enhance robots capabilities demanded by complex tasks, such as marine current turbine maintenance. We propose a Radial design for the concept of Reconfigurable Magnetic Coupling Thruster (R-RMCT). This design is based on the usage of a radial magnetic coupling as the core of a magnetic joint...
The servo motion system plays an important role in the position accuracy of the Cartesian picking robot. During the automatic picking process, the nonlinearity of friction will affect position tracking accuracy. In order to improve the position accuracy of Cartesian robot, a mechanical model considering friction is established. Furthermore, fuzzy logic controller based on PID is used to control the...
In order to design and manufacture the demonstration equipment for an automatic control theory, we focus on the strength of a MAX channels made of the aluminum alloy in expansion kit TETRIX of LEGO MindStorms. The tensile test and bending test were carried out to investigate the mechanical properties of the MAX channel and, notice on the design of the MAX channel subjected to combined load of bending...
The active mode rehabilitation robot is recently developed to help paralysis patients in improving their capability. The robot is usually completed with load and weighting mechanism. This paper presents an alternative weighting mechanism of active mode rehabilitation robot by using spiral spring as load source. PI controller is used to ensure the link reaching its last position by controlling the...
We perform a comparative analysis of energy-based performance criteria for the dynamics-based optimization of robot trajectories. The performance criteria considered include minimum torque, electrical power loss, approximation to mechanical work, and energy loss due to friction. Our dynamics model takes into account rotor inertias and gearing, and also considers robots subject to a range of motion...
Direct-drive robotics is quite attractive because of its high efficiency, high robustness and wide application prospect. This paper is to propose a new double-stator hybrid flux switching permanent magnet (DSH-FSPM) machine for the direct-drive robotic applications. The key is to integrate the distinct merits of high torque density, flux-modulation capability, high fault-tolerant capacity and low...
For the purpose of enhancing compliance of robot joint, an impedance control strategy with new inner torque controller is proposed. Apparent inertia of the motor can be scaled down thanks to this new type of torque controller. Effects of different position (motor-side position θ and link-side position q) feedback strategies are explored through theoretical deviation, simulation and static stiffness...
Knee exoskeletons can help injured subjects regain locomotion ability by providing external movement compensation as a robot-assisted rehabilitation technique. Tracking control of joint angle of knee exoskeletons often encounters time-dependent (time-varying) model parameter issues, which would dramatically put an influence up on dynamic behaviors. In a number of applications, inertial and viscous...
We describe the concept and first prototype of a novel mechatronic design of a robotic gripper, which aims at being mounted on a humanoid robot to achieve firm (i.e. locked) and robust grasps. Such grasps could ideally support complex multi-contact motions, such as ladder climbing, or manipulation of complex tools, with energy efficiency. For this purpose, we propose a solution by designing a smart...
Physical human-robot interaction is one of the hottest topic in robotics and safety issues are its fundamental aspect. The present paper contributes to this aspect in that collision detections can be completed on the servo level in an intuitive way. The principle of the proposed collision detection strategy is based on the relative difference of the feedback commanded torque, which is able to identify...
In this paper, we present the control of and experimentation on an active dual-mode twisted string actuation mechanism for automatic transmission. This mechanism has a two-stage transmission ratio and is implemented by changing the twisted radius of the string in each mode (force mode or speed mode). Control algorithms for implementing different transmission ratios are proposed and experimentally...
Kinematic compatibility is of paramount importance in wearable robotic and exoskeleton design. Misalignments between exoskeletons and anatomical joints of the human body result in interaction forces which make wearing the exoskeleton uncomfortable and even dangerous for the human. In this paper we present a kinematically compatible design of an exoskeleton hip to reduce kinematic incompatibilities,...
The use of rehabilitation exoskeleton has become an important means for the treatment of stroke patients. A hybrid exoskeleton named EFW Exo II is developed for the motor function rehabilitation of elbow, forearm and wrist. The EFW Exo II is based on a parallel 2-URR/RRS mechanism and a serial R mechanism. It could fit both left and right arms for the symmetrical and open structure, and the distance...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.