The authors present a novel control method to suppress the torsional vibration of a flexible joint which connects the motor shaft and the driven link. To obtain the stability against the torsional vibration, it is nec...
详细信息
The authors present a novel control method to suppress the torsional vibration of a flexible joint which connects the motor shaft and the driven link. To obtain the stability against the torsional vibration, it is necessary to insert an artificial damper element to some extent in the control law. Estimated link velocity is fed back for damping. This link velocity is estimated by an observer without using any sensor for the link portion. For the purpose of the estimation, an acceleration controller which is realized by a disturbance observer, is applied. The experimental results are shown to verify the proposed method.< >
The authors focus on a scheme for searching for a contact point between a multifingered hand and an unknown object. They propose an active touch approach using joint compliance from the viewpoint of considerably reduc...
详细信息
The authors focus on a scheme for searching for a contact point between a multifingered hand and an unknown object. They propose an active touch approach using joint compliance from the viewpoint of considerably reduced hardware improvement. The algorithm is composed of two phases. One is the approach phase, in which each finger first is opened widely and approaches an object until a part of a finger link is in contact with the object. The other is the detection phase, in which each finger posture is changed by slip while maintaining contact between object and finger. With a suitable combination of compliant joints and position-controlled joints, a finger link has the capability of changing its posture while maintaining contact with an object over a small angular displacement at a particular joint. This is defined as self-posture changeability (SPC). The condition leading to SPC is discussed for a general n-link system. The algorithm is confirmed through simple experiments using a two-fingered robot hand with the capability of joint compliance.< >
This paper focuses on a scheme for searching for a contact point between a multifmgered hand and an unknown object. Instead of mounting a attributed tactile sensor all over the finger links, we propose an active touch...
详细信息
Focuses on a scheme for searching a contact point between a multifingered hand and an unknown object. Instead of mounting a distributed tactile sensor all over the finger links, the authors propose an active touch app...
详细信息
Focuses on a scheme for searching a contact point between a multifingered hand and an unknown object. Instead of mounting a distributed tactile sensor all over the finger links, the authors propose an active touch approach using joint compliance. The algorithm is composed of two phases. One is the approach phase, in which each finger is opened widely and approaches to an object until a part of a finger link is in contact with the object. The other is the detection phase, in which each finger posture is changed with slip while maintaining contact between object and finger. Using two selected postures during the detection phase, one can compute the intersecting point which leads to an approximate contact point. With a suitable combination of compliant joints and position-controlled joints, a finger link has the capability of changing its posture while maintaining contact with an object over a small angular displacement at a particular joint. This motion is essential in the contact point detection phase. The proposed algorithm is confirmed through simple experiments using a two-fingered robot hand.< >
The authors propose a novel control method based on two observers to suppress the vibration of a flexible joint, even under fast motion. One observer is a disturbance observer and is used for the realization of an acc...
详细信息
The authors propose a novel control method based on two observers to suppress the vibration of a flexible joint, even under fast motion. One observer is a disturbance observer and is used for the realization of an acceleration controller of the motor axis. The other observer estimates the link velocity and is effective for the suppression of torsional vibration. The disturbance observer estimates the total sum of the disturbance torques which are imposed on the motor axis. Feedback compensation by this estimated disturbance torque increases the servo stiffness and the robustness of the motor portion. The feedback of the estimated link velocity totally suppresses the torsional vibration of the flexible joint even under fast motion. The proposed control was implemented in a 16-b microprocessor with a digital signal processor for a laboratory test.< >
A finger-shaped tactile sensor consisting of a charge-coupled device (CCD) and a semispherical optical waveguide covered with an elastic sheet and connected to a light source is proposed. The principle of the sensor i...
详细信息
A finger-shaped tactile sensor consisting of a charge-coupled device (CCD) and a semispherical optical waveguide covered with an elastic sheet and connected to a light source is proposed. The principle of the sensor is based on producing the scattering light at the sensor-object contact. The contact location is recognized using a CCD to detect light. By a simple calculation of the equation derived from the sensor surface geometry, the sensor can also provide the surface normal of the touched object. Through experiments using a prototype sensor, the fundamental characteristics of the sensor are evaluated and the principle of the sensor is confirmed.< >
Based on analyses of human skeletal muscles, a new compliance control method for robotic arms, named a Direct Compliance Control method (DCC), is proposed. The relation between the compliance of the end-point and that...
详细信息
A high resolution tactile sensor of pressureto-light conversion type, which can be used for two dimensional object profile recognition was developed. In order to obtain high resolution tactile images, the sensor syste...
详细信息
暂无评论