An Ultrasonic Standing-wave-actuated Nano-positioning Walking Robot: Piezoelectric-metal Composite Beam Modeling

Abstract

This paper proposes a design for a precision positioning miniature walking robot using piezoelectric unimorph actuators. The theoretical working equations of a uniform piezoelectric unimorph beam are derived based on the linear piezoelectric relations, Hamilton’s principle, and Euler-Bernoulli beam equation. Themodal superposition method is used to determine the response of the forced transverse vibration of the beam under the effect of electrical signal inputs to the patterned piezoelectric element. Two standing waves corresponding to the third and fourth bending vibration modes are utilized to achieve the bi-directional walking mechanism for a miniature positioning robot. Design strategies and the fabrication method for the proposed walking robot are introduced. Preliminary performance tests of the robot prototype are carried out successfully, and the robot achieves speeds of 5.86 cm/sec and 3.37 cm/sec in forward and backward motion, respectively.

Dynamic analysis of microrobots with Coulomb friction using harmonic balance method

“…Figure 6 shows the dimensionless average velocity of the microrobot, a, as a function of g, χ , ϕ, and μ. To demonstrate the accuracy of the results obtained from HBM, the authors also calculate the variation of nondimensional velocity of microrobot versus aforementioned configuration parameters based on numerical integration of the equation of motion (see (11)) and based on the solution presented by Chatterjee [17] from MDPM.…”

“…The accuracy of the obtained solution directly depends on the number of terms used in this approximation. Substituting (12) into (11) and equating the coefficients of each of the lowest harmonic terms to zero, we achieve a set of equations to be solved for the unknown constants.…”

“…However, the complicated nature of the friction phenomenon often prevents the microrobotic researchers from developing analytical studies on the concept of friction-based locomotion principles [2,[9][10][11][12][13]. Although it is more elaborate to obtain an analytic solution than a numerical one for a given nonlinear problem, the analytical studies retain their convenience, specifically for simplifying the effect of complicated nonlinearities in terms of some simple expressions.…”

Concept design of novel bio-inspired distributed actuators for space applications

“…Locomotion capability could be improved by using distributed actuators at the interface between the robotic platform and the planetary surface. Preliminary prototypes of distributed systems based on piezoelectric materials have been the subject of deep investigation to perform fine positioning of autonomous micro-tool carriers for industrial use [10]. …”

“…2 shows a concept design of an active surface capable to transport and locate samples in different areas. Simple prototypes of self-actuated surfaces have been proposed in [9,10].…”