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The traditional drawing system based on the 2-D mouse can not realize the haptic interaction between operators and virtual environment. This is not available for operator to feel the interaction sensitivity. A virtual space painting system based on transparency haptic interaction is proposed. This system uses the admittance type haptic device as the information interaction interface between operators...
Friction in the electro-hydraulic servo system makes tracking and pointing accuracy lower, it is one of the most important influence factors. This paper proposes a nonlinear adaptive friction compensation method based on analysis of the position-control system of valve-control asymmetrical hydraulic cylinder and the LuGre friction model. Dual nonlinear observers were constructed to estimate the friction...
There are a lot of dead zone in many controlled systems. Different from other non-linear characteristics, dead zone has its special non-linear characteristics, which needs compensation measures in order to achieve the desired effect. By analysis of dead-zone non-linear characteristics, multi-joint robot models, and control simulation of two-joint robots, this paper is aimed to design fuzzy compensator...
In this paper, the H∞ control method as the static acceleration feedback was put forward concerned with structural uncertainty and actuator saturation. The sufficiency and necessary condition that the controller existed was proved. By simulation, it was shown that the structure could hold the favorable stability by H∞ robust control technique.
In this paper, the Generalized Prandtl-Ishlinskii model is used to design an adaptive controller for a class of nonlinear systems which contain hysteresis phenomenon in their internal dynamics. In contrast to the systems in which hysteresis appears in their input, the inverse based methods can not be applied to systems with hysteresis in their states. The proposed controller is able to cope with different...
High resolution optical equipment needs a low noise environment, to realize high precision pointing and tracking function. However, the vehicular optical equipment will be influenced by the disturbance of vehicle body when the vehicle is moving. To solve this problem, a large stroke vibration isolation Hexapod platform with hydraulic actuator was proposed. A prototype platform and an experiment system...
This paper considers an adaptive positioning control problem using adaptive velocity estimator. Previous adaptive control methods, the control strategy requires full-states measurements, such as position and velocity measurements. In the practical case, only the position is measured by using position sensors, therefore, we have to make a velocity signals. Making a velocity signal component, an approximate...
Design of a novel under-actuated finger was proposed in this paper. The coupled gesture-changeable finger overcomes disadvantages of two convenient kinds of under-actuated finger: coupled finger and self-adaptive finger. Decided by different grasping targets, the finger's operation process is divided into three kinds: coupled only process, self-adaptive only process and coupled self-adaptive process...
To access to the terrains that may be soft and hard, even and uneven, a novel robot (NEZA-I) with the self-adaptive mobile mechanism has been developed. Its mobile mechanism consists of two symmetric transformable wheel-track (TWT) units. Each TWT unit is driven by only one servo motor, and can efficiently move over rough terrains by changing the locomotion mode or by transforming the track configuration...
The piezo-actuated stage is composed of a piezo electric actuator (PEA) and a positioning mechanism (PM). Due to the existence of hysteretic nonlinearity in the PEA and the friction in the PM, the high precision control of the piezo-actuated stage is a challenging task. This paper discusses the high precision adaptive control for the piezo-actuated stage, where the hysteresis is described by Prandtl-Ishlinskii...
This paper presents an adaptive haptic control for a one degree-of-freedom surgical device. The control addresses the problem of hitting a solid object too hard in the presence of time delay. The proposed control runs in the inner-loop, with no time delay, and follows commanded forces from the outer loop. A Lyapunov-stable backstepping-with-tuning-functions design provides a way to ensure smooth forces...
In order to extract energy from sea waves it is necessary that the motion of Wave Energy Converters (WECs) is properly controlled. This is even more crucial for devices like buoys, whose dimensions are small compared to the wavelength of incident waves. In this paper a control approach which is adapted on a wave-to-wave basis and that employs also a reactive component in addition to the damping one...
The piezo-actuated stage is composed of a piezo electric actuator (PEA) and a positioning mechanism (PM). Due to the existence of hysteretic nonlinearity in the PEA and the friction in the PM, the high precision control of the piezo-actuated stage is a challenging task. This paper discusses the high precision adaptive control for the piezo-actuated stage, where the hysteresis is described by Prandtl-Ishlinskii...
In this paper, the problem of position and force control of a robotic manipulator in contact with the environment is considered. The Hybrid Impedance Control (HIC) methodology is employed to control the position of the end-effector in such a way that the robot exhibits a desired dynamic property and hence desired Impedance which in turn results in tracking the interaction force. It is assumed that...
An Articulated hand model was designed and built by CAD-CAM software, analyzed by finite element in the structure; the hand was made for a 3D printer in a first time, the construction of each finger suggested a mathematical model that describes the Inertia Matrix, Gravitational Matrix, and the Coreolis Matrix; the resulting mathematical model is three degrees of freedom, the finger control is based...
This paper shows that remote handling procedures are a key task on future fusion power plants. In Madrid, Spain, it is planned to build a singular scientific technical facility for the development of the technologies required for future commercial fusion reactors. One of the areas will be fully dedicated to remote handling for developing and testing tasks where human presence is not allowed. This...
The force fighting exists between active channels of redundant system, which affects the output precision, shortens operation life and leads to damage. Based on the nonlinear model of dual redundant hydraulic actuation system, this paper investigates the influences of each parameter by setting them differently in two channels and brings us guidance to reduce the force fighting in design and manufacturing...
An adaptive multi-dimensional compliance model reference controller was implemented in real-time on a 4 degrees of freedom (DOF) of the humanoid Bristol-Elumotion-Robotic-Torso II (BERT II) arm in Cartesian space. The robot manipulator has been controlled in such a way as to follow the compliant passive behaviour of a reference mass-spring-damper system model subject to externally sensed forces/torques...
This paper presents a proposal of an iterative learning control method for a musculoskeletal arm to acquire adequate internal force to realize human-like natural movements. Additionally, a dynamic damping ellipsoid at the end-point is introduced to evaluate internal forces obtained through the iterative learning. In our previous works, we have presented that a human-like smooth reaching movement using...
As the computer vision and virtual reality (VR) technology become mature nowadays, there is a huge potential to connect VR with the real world. In this paper, a 3D interactive VR system with adaptive treadmill control is developed. The subject walks on the treadmill at will. Interaction force between feet and treadmill are measured to estimate the subject's intended walking speed. The treadmill belt...
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