Evidence from biomechanics research suggests that tendon series elasticity allows muscle to act in an optimal range of its force–length and force–velocity curves to achieve work and power amplification. In this investigation we put forth a simple model to quantify the capacity of series elasticity to increase work and power output from an actuator. We show that an appropriate spring constant in...

This paper reports on the development of a comprehensive nonlinear mathematical model of a novel inherently compliant fluidic actuator with Rotary Elastic Chambers (REC–actuator). The actuator is intended for robotic devices working in direct physical contact with humans and can be operated by both, liquid as well as gaseous working fluid. In the hydraulic realization the REC-actuator is contro...

In this paper, the active buckling control of smart functionally graded (FG) plates using piezoelectric sensor/actuator patches is studied. A simply supported FG rectangular plate which is bonded with piezoelectric rectangular patches on the top and/or the bottom surface(s) as actuators/sensors is considered. When a constant electric charge is imposed, the governing differential equations of mo...

In this paper, stability analysis of walking gaits and robustness analysis are developed for a five-link and four-actuator biped robot. Stability conditions are derived by studying unactuated dynamics and using the Poincaré map associated with periodic walking gaits. A stable gait is designed by an optimization process satisfying physical constraints and stability conditions. Also, considering...

The function of many muscles during natural movements is to accelerate a mass. We used a simple model containing the essential elements of this functional system to investigate which musculoskeletal features are important for increasing the mechanical work done in a muscle-powered acceleration. The muscle model consisted of a muscle-like actuator with frog hindlimb muscle properties, operating ...

Networked control systems (NCSs) offer many advantages over conventional control; however, they also demonstrate challenging problems such as network-induced delay and packet losses. This paper proposes an approach of predictive compensation for simultaneous networkinduced delays and packet losses. Different from the majority of existing NCS control methods, the proposed approach addresses co-d...

Several arboreal mammals have the ability to rapidly and repeatedly jump vertical distances of 2m, starting from rest. We characterize this performance by ametric we call vertical jumping agility. Through basic kinetic relations, we show that this agility metric is fundamentally constrained by available actuator power. Although rapid high jumping is an important performance characteristic, the ...