In this paper, we report the results from the analysis of a numerical model used for the design of a magnetic linear actuator with applications to fin-based locomotion. Most of the current robotic fish generate bending motion using rotary motors which implies at least one mechanical conversion of the motion. We seek a solution that directly bends the fin and, at the same time, is able to exploi...

In the last decade new actuator designs have been presented trying to introduce at mechanical level the advantages of compliance. Ranging from serial elastic actuators to different designs of variable stiffness actuators, various prototypes have been proposed and implemented on robots, thus allowing performance of novel and challenging tasks. Nevertheless some of these new devices often are aff...

This paper presents a method to optimize the energy efficiency of walking bipedal robots by more than 50 % in a speed range from 0.3 to 2.3m/s using elastic couplings – mechanical springs with movement speed independent parameters. The considered robot consists of a trunk, two stiff legs and two actuators in the hip joints. It is modeled as underactuated system to make use of its natural dynami...

Analyzing numerous or long time series is difficult in practice due to the high storage costs and computational requirements. Therefore, techniques have been proposed generate compact similarity-preserving representations of series, enabling real-time similarity search on large in-memory data collections. However, existing are not ideally suited for assessing when sequences locally out phase. I...

This article proposes a method to precisely estimate the load force of magnetic lead screw (MLS)-based series elastic actuators (SEAs) in real time. The transmissions MLS-based SEAs generally comprise permanent magnets (PMs). Owing pole distortion and characteristic nonlinear PMs, conventional estimation methods are less accurate for than with mechanical springs. In proposed method, MLSs, an ML...

The series elastic actuator (SEA) is generally used as the torque source of exoskeleton robot for human–robot interaction (HRI). In this paper, an impedance control method lower limb robots driven by SEA presented. First, considering low-frequency vibrations generated during walking, displacement regarded external disturbance to motor. An structure with negative stiffness (NSS) designed achieve...

The High Redundancy Actuator (HRA) project investigates the use of a relatively high number of small actuation elements, assembled in series and parallel in order to form a single actuator which has intrinsic fault tolerance. Both passive and active methods of control are planned for use with the HRA. This paper presents progress towards a multiple model control scheme for the HRA applied throu...

C-blocks are unique piezoelectric building blocks which can be combined in series or parallel to generate tailorable performance and exploit the advantages of bender and stack architectures. This paper presents a complete theoretical model that predicts the force-deflection behavior for any generic C-block actuator array configuration. An experimental investigation with five case studies is des...

The technique used to control the airflow is based on the electro-hydrodynamic actuator which is also called plasma actuator. This actuator ensures the airflow control thanks to the electric wind created by the electrical corona discharge. This ionic wind is developed at the profile surface tangential to the initial free airflow so that it has a significant effect on the boundary layer flow. Th...