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We have discussed the development of a linear actuator using IPMC materials and its applications to a walking robot and a snakelike robot. In this monograph, the doping effects on motion were focused on especially, and it was shown by numerical simulations of walking control and by an experiment of a swimming control of the snakelike robot that the properties of the actuator can be adjusted according to particular motions, i.e., slow speed motion with low energy consumption or high speed motion with high energy consumption. Also, a possibility that some actuators distributed in a system can be partially doped with a desired ion by moving the actuators mechanically was shown by a preliminary experiment. The authors consider that the developed IPMC linear actuator can be used for biomimetic control systems where the properties of the system can be adapted to an environment using doping effects. To apply the artificial muscle actuator to a general robotic system, there exist a lot of problems such as limitation of output force; however, we think the mutual evolution of improvement of actuator technology and design of control system is important for further applications. [ABSTRACT FROM AUTHOR]

In this study, we described the analytical framework for deriving the dynamic model of the segmented IPMC. For the electromechanical property of the IPMC, a simple RC model is used and the finite-element approach is used for dynamic modeling of the mechanical portion of the segmented IPMC. The proposed modeling approach can be used for designing various controllers for effective underwater propulsion and other robotics applications where soft and complex motion are required. The proposed segmented IPMC can be a possible solution because each segment of the IPMC can be bent individually. The state space equation developed using a large deflection beam model was simulated for different input voltages, and simulation results show that the proposed model can be effectively used for estimating the motion of the segmented IPMC in various applications. [ABSTRACT FROM AUTHOR]

In this paper, we described several robotic applications developed using IPMC materials, which the authors have been developed as attractive soft actuators and sensors. We introduced following unique devices as applications of IPCM actuators: (1) haptic interface for virtual tactile displays, (2) distributed actuation devices, and (3) a soft micromanipulation device with three degrees of freedom. We also focused on aspects of sensor function of IPMC materials. The following applications are described: (1)a three-DOF tactile sensor and (2)a patterned sensor on an IPMC film. [ABSTRACT FROM AUTHOR]

Polypyrrole actuators are low-voltage (1-3 V), moderate to large strain (2-35%), and relatively high stress (up to 34 MPa) actuator materials. Strain rates are moderate to low, reaching 11%/s, and frequency response can reach several hertz. Faster response (> 1 kHz) is anticipated in nanostructured materials. Forces can be maintained with minimal power expenditure. This chapter reports on the current status and some of the anticipated properties of conducting polymer actuators. Applications investigated to date include braille cells, shape changing stents, and variable camber foils. Situations where low voltage operation is valuable and volume or mass are constrained favor the use of conducting polymers. Polypyrrole and other conducting polymers are typically electrochemically driven and can be constructed in linear or bending (bilayer) geometries. Synthesis can be by chemical or electrochemical means, and raw materials are generally very low in cost. These polymers are electronically conducting organic materials. They also allow ions to diffuse or migrate within them. An Increase in the voltage applied to a polymer electrode leads to removal of electrons and an increasingly positive charge within the volume of the polymer. This charge is balanced by negative ions that enter the polymer from a neighboring electrolyte phase (or by positive ions that leave). Ion insertion is generally accompanied by expansion of the polymer. The ions, solvent, and synthesis conditions determine the extent of this expansion, which can be anisotropic. A change in modulus has also been observed as a function of the oxidation state. Models relating charge, strain, voltage, stress, and current have been developed that allow designers to evaluate the feasibility of designs. One of these modeling approaches is presented with the aim of enabling selection of appropriate device geometry. The field of conducting polymer actuators is developing rapidly with larger strains, stresses, cycle lifetimes, and rates reported every year. The background needed to understand these developments and to decide if polypyrrole and in general conducting polymer actuators are appropriate for use in a given application is provided. [ABSTRACT FROM AUTHOR]

It can be seen from the above reported research and the scale of the academic interest in active polymer materials, that they have the potential to become an indispensable part of future technological developments. With each polymer having its own niche applications, they are bound to be the materials of future. With growing emphasis on interdisciplinary research, different active materials can be combined to develop tailor-made, multifunctional properties, where single materials can act as sensors, actuators, structural elements, etc. To date, the robotics community has adopted only two major active polymer technologies: dielectric elastomers and ionic polymer-metal composites because the maturity of these two technologies is inevitable. However, other technologies are also quite promising and leaves one the great potentials to use them in robotic applications. Two other technologies that the robotics community is currently considering are conducting polymers and electrostrictive graft elastomers. In later chapters, we will focus on four major active polymer technologies: dielectric elastomers (Chapters 2 and 3), electrostrictive graft elastomers (Chapter 4), conducting polymers (Chapter 5), and ionic polymer-metal composites (Chapters 6-10). We all expect that the robotics community will adopt other promising active polymer materials as their maturity and availability improve. [ABSTRACT FROM AUTHOR]

Research and development of the dielectric elastomer actuator have produced significant progress for decades. A remarkable amount of work has focused on delivering the feasibility of the industrial application of the material. However, few commercial products equipped with polymer actuators have been introduced in the market, probably because most of the research has been dedicated either to discovering new actuation properties of the polymeric material or comparative study of the operating range of a particular traditional actuator and its polymeric substitute. One of the implications of the term "actuator" might be a "controllable" motion generator. If a material produces just some motions, it can not be referred as an actuator unless its motions are controlled. The actuator designs introduced in this chapter have been developed under a common philosophy that actuator motions should be controllable with a reasonable amount of control actions. This clearly differs from many previous developments. The physics of the polymeric material actuation and its construction as an actuator is quite straightforward if a proper application is well sought in advance. In other words, if a good application where the polymer actuators can be used is established and the actuator functionality is well defined, application of the current dielectric elastomer actuator technology to industrial products could be accomplished before long. Future research activity may focus on development of a new energy effective material that has higher permittivity and creation of new application fields such as biomimetic robotics and tactile or braille displays. [ABSTRACT FROM AUTHOR]

Foot groping is one way to evaluate the stability of footholds for legged locomotives on rough terrain. For further acquisition of ground information, we installed active ankles with two active joints on the experimental quadruped vehicle, RoQ2. To compensate the loss of passive adaptation of ankles to terrain, active adaptation using COF estimation is implemented. COF is a center of pressure on a sole and estimated by sole sensor, which consists of four FSRs. Sole sensors for COF can determine the sole plane when adapting to rough terrain. This paper also shows that our new proposition can detect an edge of a beam or a step on the ground without thrusting a foot to the objects. Keywords: COF, quadruped vehicle, rough terrain, adaptation, RoQ [ABSTRACT FROM AUTHOR]

The RoboCup-Rescue project [1] was proposed, that aims at disaster mitigation, and we implemented a simulation system for it. The image of the system is shown in Figure:1. Making agents that maximize the rescue activity in this simulation system provides new problem domains compare to the Soccer Server [2], such as, cooperation between heterogeneous agent, dynamic planning reorganization and more strict limitation of sensor information. [ABSTRACT FROM AUTHOR]