There is no trade-off between speed and force in a dynamic lever system.

There is always a trade-off between speed and force in a lever system: comment on McHenry (2010).

Dynamic Analysis of Moving Cables with Variable Tension and Variable Speed

Dynamic Analysis of an axially moving cable with time dependent tension and velocity isstudied in this paper. Tension force and the moving speed are assumed to be harmonic.It is found that there exists a specific value of speed in which natural frequency of the system approacheszero. This specific speed for such a critical condition is called critical speed and it will be proved thatincreasing ...

Nonlinear Dynamic Modeling and Hysteresis Analysis of Aerospace Hydro - dynamical Control Valves

A new procedure for deriving nonlinear mathematical modeling for a specific class of aerospace hydro - mechanical control valves is presented. The effects of friction on the dynamic behavior of these types of valves along with the experimental verifictions are also given. The modeling approach is based on the combination of the following three tasks: decomposition of the valve into simple speci...

The paradox of the weakening combatant: trade-off between closing force and gripping speed in a sexually selected combat structure

1. Previous evidence demonstrates that closing force decreases proportionally as fiddler crab claw size increases. Larger crabs do have greater absolute closing force, but less than would be expected if claw proportions were isometric. In the Mud Fiddler Crab, Uca pugnax , this is explained by a decrease in mechanical advantage with increasing claw size. 2. We here re-measure mechanical advanta...

DRIVING OPTIMUM TRADE-OFF BETWEEN THE BENEFITS AND COSTS OF INTERBASIN WATER TRANSFER PROJECTS

The interbasin water transfer is a remedy to mitigate the negative issues of water shortage in arid and semi-arid regions. In  a water transfer project  the receiving basin always  benefits while, the sending basin may suffer. In this study, the project of interbasin water transfer from Dez water resources system in south-west of Iran to the central part of the contrary is  investigated during...