An advantage of crawler mechanism is a stable navigation on uneven terrain. So many of rescue and field robots adopt such a mechanism. However, the mechanism has a problem of slippage with the ground in case of circling motion of the robot. To achieve dead-reckoning of a crawler robot, it is necessary to consider its slippage. In this research, we proposed a method to estimate slippage of crawlers quantitatively by using current sensors.These sensors measure current of motors driving crawlers. The proposed method was verified by our experiment using a crawler robot.
The purpose of this study is to develop a wearable personal mobility with which user can perform the following five kinds of motion by his actions. The five kinds of motions are 1: going forward and backward motion in a plane, 2: turning to right and left side, 3: walking, 4: going up and down a step, 5: striding over obstacles. We propose a pair of wearable wheel-leg type personal mobility which are attached under the user's right and left shoes independently. It is driven by electrical power source. In order to give easy and instinctive operation to the user, the translational velocity of the each mobility are controlled independently to right and left mobility according to the variation of the each angle of lower legs in those motions. In this paper the developed wearable mobility and the interface for the operation are reported. Then the results of the experiments on those five kinds of motion with the developed mobility are shown and some findings on the mobility are added.
This paper discusses a dynamic nonprehensile manipulation by using a vibrating plate. The manipulation method, where 2-DOF (degrees of freedom) translational motion of a object on the plate surface is controlled by a single active joint, is proposed. For the plate vibration mechanism, we first introduce the active-passive hybrid joint with viscoelasticity. This mechanism features that the plate vibration direction is variable based on the input frequency of the active joint. We then analytically derive the trajectory of the object on the vibrating plate. Through this analysis, we reveal that 2-DOF translational motion of the object can be controlled by using the variable vibration direction. After showing the relationship between the viscoelasticity of the passive joint and the object's translational velocity, we further discuss the optimum design parameter. Finally, we show experimental result by using the prototype robot, for confirming the validity of the proposed method.
Operativity will be spoiled if the thick cable of an end effector is in the exterior of a manipulator. The less wiring device adapting Power Line Communication technology has been developed. Transmission of the information and transfer of power on an end effector are realizable with one pair of twisted pair wires. The technical details, peripheral technology, example of application and future subjects of this device which can be used, such as not only a robot but onboard equipment and plant apparatus, are reported.
It is so difficult for many people to handle other's body. Japan's aging population, the skill of lift-up motion and transfer motion is needed in the nursing care field. Utilizing self body dynamics and understanding other's movement are important to these nursing-care motions. Yoshinori Kouno, who has studied several skills related to physical, including martial arts and nursing-care motions, as the participant, we studied these motions and analyzed the techniques that were superior to other motion skills. From measurement result of pulling-up motion, we find acceleration of center of mass increases sharply by discontinuous change of zero moment point, Kouno pulled other's body up using the instantaneous. To pull the standing other's body, Kouno uses strategy of ``falling momentum,'' and Kouno constrains the movement of his arms. Therefore, we conclude that knacks of pulling-up motion are the changing ZMP by the stepping motion and constraining the arm joints. Based on these analysis result, we construct the dynamics model and control strategies, confirmed by numerical analysis and dynamic simulation. Then, to confirm the effectiveness of these skills, we perform the validation experiments on general participants instructed with these knacks.