Direct-Drive Ultrasonic Motors provide many advantages over classical electromagnetic motors. This application of an ultrasonic piezo motor in a high precision, low-power precision rotation stage explains why. The new theodolite achieves higher speed, performance and and precision based on PILine ultrasonic piezo motors.
Precision speed and setting behavior are essential characteristics of Moving Systems.
These attributes play a vital role for surveyors for example. Leica Geosystems the leading manufacturer of high-precision surveying instruments is setting a new standard for the future by using an alternative drive technology.
Their latest generation of total stations uses ultrasonic piezo motor s from PI. They allow the measuring optics to be rotated more rapidly about the horizontal and vertical axis and does comply with the demand for shorter positioning times with small step sizes for the highest accuracy.
At the same time the acceleration, the settling behavior and the angular resolution had to be improved. The objective was exceeded by far – but how does this progressive drive principal operate.
Two ultrasonic piezo motors generate the rotation. The motors are pre-loaded tangentially against a drive ring which is pivot mounted and clamped by the preload in the rest position. In operation the ceramic piezo motors oscillate with ultrasonic frequencies, the oscillation causes the friction tip to lift and displace linearly several thousand times per second. In conjunction with the preloading this produces a fast feed motion for the friction ring. This simple principle of direct power transmission refrains from using mechanical components such as gears as all lead screws in favor of higher reliability.
Linea motions can also be realized – the tangential drive principal was then applied to a straight tracked friction bar. The motion this produced attains a speed of up to half a meter per second and a force have several tens of Newton’s. The performance characteristics are variable depending on the type and number of actuators used
The drive itself is easy to integrate similar to a classic motor lead screw combination with its PILine series, PI now offers a broad range of positioning systems with ultrasonic piezo motors. PIline offers users an alternative drive solution to DC, stepper or direct-drive magnetic linear motors for better compactness higher speed and efficiency.
Product examples at https://www.pi-usa.us/products/precision_positioning_pi-micos/Precision_Rotary_Stages_Goniometers_Mc.php#Piezo_Rot
https://www.piezo-motor.net
Post time: Jun-12-2017