The magnetorheological elastomer is promising material for applications in soft robotics. Its properties like reactive to external magnetic field and softness allow to construct an attractive devices. This work presents a construction of soft gripper assembled with magnetorheological elastomers. The work describes the detailed molding process of magnetorheological elastomers. Further, the electromechanical properties of magnetorheological elastomers are shown using a simple beam. Finally, the soft gripper is constructed and analyzed with the series of experiments.

This paper presents modeling and infinite-time suboptimal control of a quadcopter device using the state-dependent Riccati equation (SDRE) method. It establishes a solution to the control problem using SDRE and proposes a new procedure for solving the problem. As a new contribution, the paper proposes a modified SDRE-based suboptimal control technique for affine nonlinear systems. The method uses a pseudolinearization of the closed-loop system employing Moore–Penrose pseudoinverse. Then, the algebraic Riccati equation (ARE), related to the feedback compensator gain, is reduced to state-independent form, and the solution can be computed only once in the whole control process. The ARE equation is applied to the problem reported in this study that provides general formulation and stability analysis. The effectiveness of the proposed control technique is demonstrated through the use of simulation results for a quadrotor device.

Recently, magnetorheological elastomers have become interesting smart materials with many new designs for robotics. Various applications have been built with magnetorheological elastomers, such as vibration absorbers, actuators, or valves, showing that this material is promising for industry applications. The objective of this study is to demonstrate that magnetorheological elastomers supported by a permanent magnet can create a soft gripper suitable for handling small and delicate objects such as fruits or candies. The novel concept of the gripper is proposed, exploring the features of a magnetorheological elastomer and a permanent magnet. This gripper uses the energy of a permanent magnet to provide a self-closing gripping mechanism. At the same time, the use of flexible material—elastomer allows it to hold delicate objects of various shapes. The effect of wrapping magnetorheological elastomer around a permanent magnet, the design process, and the characteristics of a soft gripper are presented. The effectiveness of the soft gripper was validated in a series of experiments that involved lifting various objects.

Purpose: The purpose of the paper is to present modeling and control of a nonlinear mechatronic system. To solve the control problem, the modified state-dependent Riccati equation (SDRE) method is applied. The control problem is designed and analyzed using the nonlinear feedback gain strategy for the infinite time horizon problem. Design/methodology/approach: As a new contribution, this paper deals with state-dependent parametrization as an effective modeling of the mechatronic system and shows how to modify the classical form of the SDRE method to reduce computational effort during feedback gain computation. The numerical example compares described methods and confirms usefulness of the proposed technique. Findings: The proposed control technique can ensure optimal dynamic response, reducing computational effort during control law computation. The effectiveness of the proposed control strategy is verified via numerical simulation. Originality/value: The authors introduced an innovative approach to the well-known SDRE control methodology and settled their research in the newest literature coverage for this issue.