14 accepted papers
Effective impact mitigation strategies are cru- cial for preventing potential damage to both robotic sys- tems and their operational environments during high-velocity and dynamic maneuvers, as well as during the execution of high-precision tasks. The successful implementation of impact mitigation st…
For robots with low rigidity, determining the robot's state based solely on kinematics is challenging. This is particularly crucial for a robot whose entire body is in contact with the environment, as accurate state estimation is essential for environmental interaction. We propose a method for simul…
Effective impact mitigation strategies are crucial for preventing potential damage to both robotic systems and their operational environments during high-velocity and dynamic maneuvers, as well as during the execution of high-precision tasks. The successful implementation of impact mitigation strate
For robots with low rigidity, determining the robot's state based solely on kinematics is challenging. This is particularly crucial for a robot whose entire body is in contact with the environment, as accurate state estimation is essential for environmental interaction. We propose a method for simul
Grasping an unknown object is difficult for robot hands. When the characteristics of the object are unknown, knowing how to plan the speed at and width to which the fingers are narrowed is difficult. In this letter, we propose a method to realize the three functions of simultaneous finger contact, i
Dexterous manipulation using an under-actuated hand has been a challenging task due to its non-linear dynamical characteristics. For a linkage-based under-actuated hand designed to be used to grasp and manipulate large, heavy, and rigid objects stably, precision grasping is necessary, which makes th…
This study focuses on replicating the muscu-loskeletal system of human arms for mimicking its movement. Muscle redundancy is critical for regulating the mechanical impedance of arms and legs. However, when implementing muscle redundancy on robots, making an ill-posed problem that cannot determine th…
A twisted and coiled polymer fiber (TCPF) is a soft thermal actuator increasingly used in current robotics applications. When implementing TCPF in robotics applications, amplifying the TCPF strain and force is necessary to obtain the desired performance. Therefore, this study proposes a mechanism to
This study proposes a novel twisted and coiled polymer fiber (TCPF) actuator fabricated from a polymer-coated optical fiber. The TCPF actuator is a soft actuator that is driven by heating; the TCPF actuator in combination with a cooling system has been widely studied for applications in robotics. Se
This paper proposes a novel force controller that serially combines admittance and impedance controllers. The proposed controller is adaptable to an unknown changeable environment in terms of stiffness, and it is able to achieve high control accuracy and stable operation. First, conventional admitta…
A twisted polymeric fiber (TPF) actuator often referred to as a fishing line/sewing thread artificial muscle, is one of the soft actuators which is made by twisting and heating a nylon fishing line. There are mainly two types of the TPF actuator, one is to make a contraction motion, which is sometim
In this letter, an angular trajectory tracking controller for a twisted polymeric fiber (TPF) actuator by the combination of a model-based feed-forward and estimated temperature feedback is proposed. TPF actuator is one of the soft actuators that can produce a rotational motion, which is made by twi
This letter proposes a feedforward (FF) controller for the twisted and coiled polymer actuator (TCPA), the so-called fishing line/sewing thread artificial muscle, based on its macroscopic nonlinear model. TCPA is an artificial muscle, and it contracts up to 50% in response to heating. Although sever
We propose an evaluation method of grasp stability which takes into account the elastic deformation of fingertips from the viewpoint of energy. An evaluation value of grasp stability is derived as the minimum energy which causes slippage of a fingertip on its contact surface. To formulate the evalua…