*Article* **Single Cylinder-Type Piezoelectric Actuator with Two Active Kinematic Pairs**

#### **Ramutis Bansevicius 1,†, Jurate Janutenaite-Bogdaniene 2,\*,†, Vytautas Jurenas 1,†, Genadijus Kulvietis 2,†, Dalius Mazeika 2,† and Asta Drukteiniene 2,†**


Received: 27 September 2018; Accepted: 2 November 2018; Published: 15 November 2018

**Abstract:** There is an ever-increasing demand for small-size, low-cost, and high-precision positioning systems. Therefore, investigation in this field is performed to search for various solutions that can meet technical requirements of precise multi-degree-of-freedom (DOF) positioning systems. This paper presents a new design of a piezoelectric cylindrical actuator with two active kinematic pairs. This means that a single actuator is used to create vibrations that are transformed into the rotation of the sphere located on the top of the cylinder and at the same time ensure movement of the piezoelectric cylinder on the plane. Numerical and experimental investigations of the piezoelectric cylinder have been performed. A mathematical model of contacting force control was developed to solve the problem of positioning of the rotor when it needs to be rotated or moved according to a specific motion trajectory. The numerical simulation included harmonic response analysis of the actuator to analyze the trajectories of the contact points motion. A prototype actuator has been manufactured and tested. Obtained results confirmed that such a device is suitable for both positioning and movement of the actuator in the plane.

**Keywords:** piezoelectric actuators; positioning; trajectory control; numerical analysis; trajectory planning
