Design, Analysis and Experimental Performance of a Bionic Piezoelectric Rotary Actuator

This article presents the piezoelectric ultrasonic linear actuator based on binate feet driving. The actuator is equipped with a rhombus binate feet mechanism to generate two synchronous rectangle ...

Novel design, analytical and experimental studies of a piezoelectric ultrasonic linear actuator based on binate feet driving

A resonant-type piezoelectric screw motor for one degree of freedom (1-DOF) positioning platform is proposed, fabricated, and investigated in this article. The motor comprises a driver and a screw rod. The driver is composed of four transducers, a nut seat, and a flange nut. The flange nut is bolted connected on the nut seat, and the four piezoelectric transducers are connected with the nut seat by right-angle flexible hinges. Each piezoelectric transducer comprises two piezoelectric stacks and one displacement amplifier. Driven by the four piezoelectric transducers, elliptical vibration is generated by the driver, which is used to actuate the screw rod to realize the linear movement. The driver is analyzed using the finite element analysis software ANSYS. The proposed motor and positioning platform prototype are manufactured, assembled, and tested. The performance of the developed piezoelectric screw motor shows its applicability and effectiveness for the 1-DOF positioning platform with a large force. Experiments demonstrate that the maximum velocity of this motor is 10.53 mm/s without mechanical load and the maximum output force of the platform can reach 17.19 N when the excitation voltage is 230 at 365 Hz.

/pdf/resonant-type-piezoelectric-screw-motor-for-one-degree-of-2ew7nroiab.pdf

Resonant-Type Piezoelectric Screw Motor for One Degree of Freedom Positioning Platform Application

With the rapid development of science and technology, positioning technology has been widely used in people’s daily lives and related scientific research activities. However, the traditional positioning system mostly uses GPS for positioning, and then transmits the positioning information to the remote server through GPRS / GSM, but it is not applicable in remote mountain areas where some base station signals cannot reach. Moreover, the accuracy of single GPS positioning is difficult to be guaranteed. This paper mainly studies the design of Beidou-GPS dual-mode positioning system based on Android platform mobile communication equipment. First, analyse the composition of the satellite positioning system and design the overall architecture of the Beidou-GPS dual-mode positioning system for mobile communication equipment. Then, it analyses the most important star selection algorithm in dual-mode positioning technology, and proposes an improved star selection algorithm based on azimuth. Second, build the overall architecture of the Android platform for mobile communication devices based on dual-mode positioning. Finally, by comparing with the traditional star selection algorithm, the proposed improved positioning algorithm is experimentally verified. Simulation experiment results show that the proposed dual-mode positioning algorithm has high accuracy and can meet the real-time requirements of the system.

Beidou-GPS dual mode positioning of mobile communication equipment based on Android platform

Families of Hooke-like isotropic hyperelastic material models and their rate formulations

In this paper, a linear piezoelectric micromotor for dual-slider positioning by a single piezoelectric element (PZT) is proposed. A slider 1 and a permanent magnet are connected by the PZT, and a slider 2 is placed on the permanent magnet by the magnetic force. The slider 1 is a small steel cuboid and can be clamped and released by an electromagnet base. When it is released, it can be driven by impact friction force generated by the PZT. When it is clamped, it keeps stationary, and the slider 2 can be positioned based on the smooth impact friction drive of the micromotor. Both the sliders can be positioned independently with a long motion range as well as a high positioning resolution. Due to a single PZT used in the micromotor and miniaturized design of the mechanism, the proposed micromotor has been constructed with a compact size as well as a relatively high loading capacity.

Design and experimental validation of a linear piezoelectric micromotor for dual-slider positioning

Toward handling nonlinear coupling effects at large elastic deformations, a decoupled form of the multi-axial elastic potential for highly elastic soft materials is first constructed based on Hencky’s logarithmic strain, and this new potential is then used to obtain analytic results for the uniaxial extension and compression of a bar, the equi-biaxial extension of a plate, the plane-strain extension of a strip and, in particular, the large torsion of a thin-walled tube with free ends. Novelties are included in the following three respects: (a) Experimental data for responses of the uniaxial extension, equi-biaxial extension (uniaxial compression) and plane-strain extension (simple shear) may be accurately matched up to large strain with strain-stiffening effects; (b) exact responses for the Poynting effect of freely twisted thin-walled tubes may be derived for changes in the axial length and the wall thickness as well as the averaged radius; and (c) the coupling nonlinear complexities involved in all such responses may be worked out in a decoupled sense. 

Exact large strain analysis for the Poynting effect of freely twisted thin-walled tubes made of highly elastic soft materials

Extracorporeal membrane oxygenation (ECMO) is a rescue therapy in patients with cardiopulmonary emergencies (1, 2). Although the use of ECMO is gradually increasing, ECMO is still a very costly and invasive treatment. ECMO education programs may expand the availability of this treatment to meet growing needs (3). Fuwai Hospital is a national center for cardiovascular disease in China, and it has provided ECMO support since 2004 (4, 5). In 2019, Fuwai hospital launched a three-month education program for venoarterial (V-A) ECMO that recruited participants from all over the nation. The program was composed of didactic courses, water-drill courses, high-fidelity simulation, and clinical training. By June 2022, 10 sessions had been held. This study aimed to introduce the three-month education program for V-A ECMO and to evaluate the program by assessing the participants’ feedback.

https://doi.org/10.34197/ats-scholar.2022-0106br

Huiying Wang

Papers

Design and experimental validation of a linear piezoelectric micromotor for dual-slider positioning

Exact large strain analysis for the Poynting effect of freely twisted thin-walled tubes made of highly elastic soft materials

A Nationwide Three-Month Education Program for Venoarterial Extracorporeal Membrane Oxygenation