A survey of models, analysis tools and compensation methods for the control of machines with friction

The Theory of Matrices. By F R. Gantmacher. Two volumes, pp. 374 and 276. 1959. (Translated from the Russian by K. A. Hirsch; Chelsea Publishing Company, New York)

Dynamic analysis of flexible manipulators, a literature review

Soft robots driven by stimuli-responsive materials have unique advantages over conventional rigid robots, especially in their high adaptability for field exploration and seamless interaction with humans. The grand challenge lies in achieving self-powered soft robots with high mobility, environmental tolerance, and long endurance. We are able to advance a soft electronic fish with a fully integrated onboard system for power and remote control. Without any motor, the fish is driven solely by a soft electroactive structure made of dielectric elastomer and ionically conductive hydrogel. The electronic fish can swim at a speed of 6.4 cm/s (0.69 body length per second), which is much faster than previously reported untethered soft robotic fish driven by soft responsive materials. The fish shows consistent performance in a wide temperature range and permits stealth sailing due to its nearly transparent nature. Furthermore, the fish is robust, as it uses the surrounding water as the electric ground and can operate for 3 hours with one single charge. The design principle can be potentially extended to a variety of flexible devices and soft robots.

https://advances.sciencemag.org/content/advances/3/4/e1602045.full.pdf

Fast-moving soft electronic fish

https://people.kth.se/~dimos/DualSurvey.pdf

Short survey: Dual arm manipulation-A survey

Ionic polymer-metal composite (IPMC), which is one of the electro-active polymer actuators, is expected as artificial muscles for robots. An interesting property of IPMC is that it requires water to work, therefore it is suitable for underwater robots. In this paper, we developed an underwater robot which mimics rajiform swimming, that is the swimming form of a ray fish. Fins are designed using sixteen IPMCs. For autonomous operation, miniaturization of the electrical devices such as a micro controllers and small amplifiers are performed. A simple traveling wave control input is employed to generate moment on the fin. In the experiment, propulsion speed is measured under various control parameters. Furthermore, incremental wave of the fin is observed although the amplitude of the control input is spatially uniform. We also discuss this phenomenon from the point of view of interaction between elasticity of the actuator and fluid dynamics.

Development of a Rajiform Swimming Robot using Ionic Polymer Artificial Muscles

On the limiting zeros of sampled multivariable systems

We derive analytical models of the rebound phenomenon between a ping-pong ball and the table/racket rubber. In the rebound model of the table, the determination of the type of the contact during the impact is derived as a generalized condition in the 3-dimensional space. In the model between the ball and racket rubber, it is assumed that the kinetic energy of the tangent velocity is stored as the potential energy due to the elasticity of the rubber. This assumption leads to that the impulse in the horizontal direction is proportional to the tangent velocity. The models are verified by experimental data.

Modeling of rebound phenomenon of a rigid ball with friction and elastic effects

In aging societies, there is a strong demand for robotics to tackle problems resulting from the aging population. We have developed a prototype nursing-care assistant robot, RIBA, which was designed to come in direct contact with patients and conduct physically challenging tasks. RIBA interacts with its object, typically a human, through multiple and distributed contact regions on its arms and body. To obtain information on such whole-body contact, RIBA has tactile sensors on a wide area of its arms. The regions where hard contact with the manipulated person may occur have almost flat surfaces, leading to surface contact involving a finite area, in order to reduce contact pressure and not to cause the person's pain. When controlling the position and orientation of the person, the relative positions and orientations of the distributed contacting surfaces should be preserved as far as possible to maintain stable contact and not to graze the person's skin. Preserving the force and the pressure pattern of each contact region using tactile feedback is also important to provide stable and comfortable human-robot physical interaction. In this paper, we propose a whole-body contact manipulation method using tactile information to meet these requirements.

/pdf/whole-body-contact-manipulation-using-tactile-information-2e7l8i8235.pdf

Whole-body contact manipulation using tactile information for the nursing-care assistant robot RIBA

In aging societies, there is a strong demand for robotics to tackle problems resulting from the aging population. Patient transfer, such as lifting and moving a bedridden patient from a bed to a wheelchair and back, is one of the most physically challenging tasks in nursing care. We have developed a prototype nursing-care assistant robot, RIBA, that can conduct patient transfer using human-type arms. The basic robot motion trajectories are created by interpolating several postures designated in advance. To accomplish more flexible and suitable motion, adjustment using sensor information is necessary, because the patient's posture and positions in contact with the robot may differ slightly in each trial. In this paper, we propose a motion adjustment method in patient lifting using tactile sensors mounted on the robot arms. The results of experiments using a lifesize dummy are also presented.

/pdf/tactile-based-motion-adjustment-for-the-nursing-care-3alga8ioxo.pdf

Yoshikazu Hayakawa

Papers

Development of a Rajiform Swimming Robot using Ionic Polymer Artificial Muscles

On the limiting zeros of sampled multivariable systems

Modeling of rebound phenomenon of a rigid ball with friction and elastic effects

Whole-body contact manipulation using tactile information for the nursing-care assistant robot RIBA

Tactile-based motion adjustment for the nursing-care assistant robot RIBA