压电陶瓷电机
LEGS 压电陶瓷电机的精度达到了纳米级,具有即时响应能力,没 有回差问题。这类有直线型和旋转型两种版本。
直线型 LEGS 压电陶瓷电机极其适合要求高精度、小空间、低能耗 和结构简单的运动和抓握用途。
这种旋转型型 LEGS 压电陶瓷电机可广泛用于对于高速动态性 能和定位精度要求极高的场合。它的小体积高转矩输出也非常有 用。
Piezo motors are available as linear version or as rotary version:
Piezo LEGS Linear motors
This linear Piezo LEGS motor is ideally suited for move and hold applications where precision, minimal space, low energy consumption and simple construction are required.
Piezo LEGS Rotary motors
This Piezo LEGS rotary motor is intended for a large range of applications where high speed dynamics and positioning with precision is crucial. High torque output in a small package is also beneficial.
Electronics
Piezo LEGS motors can be used in different ways depending on the requirements of the particular application. Required resolution is always the key question. As its name implies, a Piezo LEGS motor takes steps to create motion and, just as in humans, it can walk in different ways. It can move fast or slow, take long steps, short steps or partial steps, and stop at any point. All accomplished by different movement patterns and frequencies of the legs.
If we study one of the piezoceramic legs in detail, the actuator is built like a bimorph (Figure 1). Left and right side of the leg can be independently activated (0-48V). When energized, the leg can extend and bend a few microns. The tip of the leg (i.e. the friction drive pad) can move to any point within the rhombic area as illustrated in Figure 1. When the leg is not energized, the tip of the leg will be at point a. When only activating one side of the leg, it will bend to the left or to the right (b or d respectively). With both sides of the leg fully activated, it will extend to its maximum height (at point c). A Piezo LEGS motor will have several actuator legs working together. The motion of the motor will be dependent of the input electrical waveform signals. To achieve motion, two legs (or more) are driven in parallel. In total, each motor will need four separate control signals. Each leg, however, is controlled with two voltages. In Figure 2 two different waveforms are depicted. Rhomb is a rudimentary waveform which will make the tip of the leg move in a rhombic pattern. A more advanced waveform is called Delta. The Delta waveform is optimized for smoothest walking, and is best for high precision positioning.