Storage of elastic energy is key to increasing the power output of many biological systems. Mantis shrimp (Stomatopoda) must store considerable elastic energy prior to their rapid raptorial strikes; however, little is known about the dynamics and location of elastic energy storage structures in this system. We used computed tomography (CT) to visualize the mineralization patterns in Gonodactyla...

Generally, the flexible robot system can be modeled as the two-mass system which consists of a motor and load connected by a spring. Thus, its elasticity causes resonance in the system. By using the conventional PID controller, this method cannot perform well in this situation. Much research has proceeded with the aim of reducing vibration. A new effective control method, the resonance ratio co...

A thin infinitely long elastic shell is stiffened by J in number identical lengthwise ribs distributed uniformly around the circumference and joined to a rod in the center. The 2D model of the substructure is a rigid central mass supported by J axisymmetrically placed linear springs. The response of the shell–spring–mass system is quite different from a fluid couple the displacement of the shel...

We measure electron tunneling in transistors made from C(140), a molecule with a mass-spring-mass geometry chosen as a model system to study electron-vibration coupling. We observe vibration-assisted tunneling at an energy corresponding to the stretching mode of C(140). Molecular modeling provides explanations for why this mode couples more strongly to electron tunneling than to the other inter...

We measure electron tunneling in single-molecule transistors made from C140, a molecule with a mass-spring-mass geometry chosen as a model system to study electron-vibration coupling. We observe vibration-assisted tunneling at an energy corresponding to the stretching mode of C140. Molecular modeling provides explanations for why this mode couples more strongly to electron tunneling than the ot...

This paper studies the solution behavior of a system of two coupled elastic beams connected vertically by springs. With the viscous damping collocated with the ends of the springs, the system energy decays exponentially. Our goal is to find the optimal spring-damper location which yields the best energy decay rate of the beam-spring system.

In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationar...

Even though biological legs operate amazingly springlike, they clearly deviate from a perfect spring. For instance, experimental data of human hopping and running suggest an increase in leg length and a decrease in leg stiffness between touchdown and takeoff. Here, this variability of human gait is considered as a fundamental system property and introduced via non-constant leg parameters to a 1...

This article concerns the stability of a model for mass-spring systems with positive damping and negative stiffness. It is well known that when the coefficients are frozen in time the system is unstable. Here we find conditions on the variable coefficients to prove stability. In particular, we disprove the believe that if the eigenvalues of the system change slowly in time the system remains un...

Recent developments and new results associated with Inverse Vibration Problems are reported. The derived methods may be applied to COnStluCt experimental finite element and finite difference models of certain basic vibratory systems from data which is USUdlY available from modal testing. The advantages and limitation of the methods are discussed. A stiffness matrix B mass matrix E matrix in Eq....