Fanno flow has been considered as an example of a model for pneumatic internal flows. In this paper we present simple methods for calculating approximate characteristics for the Fanno flow in consideration of the dependency of the friction factor on the Reynolds number. We also proposed a simulation method for obtaining a conductance related to a ratio of total pressures at both ends of tubes. The usefulness of the simulation is shown by comparing the simulated results with the experimental results. It was confirmed that the flow characteristics could be estimated from the physical constants of a fluid, geometrical values of tubes and boundary conditions.

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This paper presents an advanced prototype of a pneumatically-driven forceps manipulator with force sensing capability using a simple flexure joint. Structural design of the integral-machined spring employed for the joint has been improved to prevent harmful buckling of the central backbone. This improvement successfully leads to performance enhancement of the joint position control and the external force estimation. In addition, theoretical models of the joint have also been improved : kinematic model considering backlash of wire-actuation and dynamic model considering non-linearity of frictional and elastic forces. Finally, an external force estimator based on a strict continuum model is designed, and its effectiveness is experimentally verified for one-DOF and combined two-DOF motion.

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