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This paper introduces and investigates a compliant spherical 3R open chain that is obtained by the in-series connection of three identical circularly-curved beam flexures with coincident centers of curvature and mutually orthogonal axes of maximum rotational compliance. The considered open chain is intended to be used directly as a spherical mechanism in pointing devices or as a complex spherical flexure for the development of spatial parallel manipulators. The compliance matrix of the proposed chain is first determined via an analytical procedure. After finite element validation, the obtained equations are used in a parametric study to assess the influence of circularly-curved beam flexure geometric parameters on the overall stiffness performances of the considered compliant spherical 3R open chain. In addition, comparison with an equivalent compliant spherical chain employing straight beam flexures is reported to highlight the added benefits of using circularly-curved beam flexures in terms of reduced parasitic motions.

A spherical flexure is a special kind of compliant hinge specifically conceived for spherical motion. It features an arc of a circle as centroidal axis and an annulus sector as cross-section, circle and annulus having a common center coinciding to that of the desired spherical motion. This paper investigates a compliant spherical 3R open chain that is obtained by the in-series connection of three identical spherical flexures having coincident centers and mutually orthogonal axes of maximum rotational compliance. The considered spherical chain is intended to be used as a complex flexure for the development of spatial parallel manipulators. The compliance matrix of the proposed chain is first determined via an analytical procedure. Then, the obtained equations are used in a parametric study to assess the influence of spherical flexure geometry on the overall stiffness performances of the considered 3R open chain.

This paper introduces and investigates a novel Spherical Flexure (SF), specifically conceived for application on spherical compliant mechanisms. The flexure features an arc of a circle as a centroidal axis and an annulus sector as cross-section, circle and annulus having a common center coinciding to that of the desired spherical motion. In this context, each element of the SF spatial compliance matrix is analytically computed as a function of both flexure dimensions and employed material. The theoretical model is then validated by relating analytical data with the results obtained through three-dimensional Finite Element Analysis. Finally, SFs are compared to Circularly Curved-Beam Flexures (CCBFs) in terms of parasitic motions.

Pipelines are one of the most important and efficient ways for transporting energy like water, gas, oil and etc. between different places all across the world. As these pipelines are located in different conditions and situations, they are all sensitive to a wide variety of damages like vibration, so monitoring their structural behavior is an essential task. Monitoring pipeline vibration caused by cavitation through an orifice by a piezoelectric sensor is presented in this paper.

This chapter introduces and investigates a fully compliant spherical chain that is obtained by the in-series connection of two identical primitive spherical flexures with coincident center of spherical motion. The compliance matrix of the proposed chain is obtained via an analytical procedure and validated via finite element analysis. Comparison with an equivalent fully compliant chain employing straight beam hinges is also provided to highlight the added benefits when using primitive spherical flexures.

In this paper, the closed-form compliance equations for spherical flexures are derived. Each element of the spatial compliance matrix is analytically computed as a function of both hinge dimensions and employed material. The theoretical model is then validated by relating analytical data with the results obtained through Finite Element Analysis. Finally, for a generic loading condition, spherical flexures are compared to circularly curved-beam hinges in terms of secondary compliance factors and maximum stress.

In this chapter, the closed-form compliance equations for Circularly Curved-Beam Flexures are derived. Following a general modeling procedure previously described in the literature, each element of the spatial compliance matrix is analytically computed as a function of both hinge dimensions and employed material. The theoretical model is then validated by comparing analytical data with the results obtained through Finite Element Analysis. Finally, a case study is presented concerning the potential application of these types of flexures in the optimal design of compliant robotic fingers.

This paper presents a method to determine material of an unknown sample object. The main objective of this study is to design a database for specifying material of an object. We produce the database for different materials which is subjected to different forces. For this purpose we use a Polyvinidilene Fluoride (PVDF) sensor which is a piezoelectric material. Also we study the effect of changing place of sensor on our study. The detailed design was performed using finite element method analysis. Furthermore, if we have an object which we do not know its material by use of this database we can find out what this object is and how much its Yanoung's modules is. This study will be suitable for medical purposes especially minimally invasive surgery.

Introducing a suitable model for a structure to understand its behavior under different conditions of loading is very important. Mathematical modeling is the simulation of a physical structure or physical process by means of suitable analytical or numerical construct. One of suitable methods for finding deflection of a beam under different forms of loading is Finite Element Method (FEM). In this paper we find deflection of a beam using FEM based on Euler-Bernoulli and Timoshenko theory.

Vibration control is an essential problem in different structure. Smart material can make a structure smart, adaptive and self-controlling so they are effective in active vibration control. Piezoelectric elements can be used as sensors and actuators in flexible structures for sensing and actuating purposes. In this paper we use PZT elements as sensors and actuator to control the vibration of a cantilever beam. Also we study the effect of different types of controller on vibration.