PI (Physik Instrumente) introduces the new vacuum compatible N-216 NEXLINE high-load piezo linear motors. These ultra-precision nanopositioning actuators provide travel ranges to 20mm, push/pull forces to 600N (130 lb), and resolution to 0.03nm. The operating principle is based on coordinated motion of a number of highly preloaded linear and shear piezo elements acting on a ceramic runner.
NEXLINE PiezoWalk drives have many high-end applications from ultra-precision manufacturing and semiconductor test equipment to astronomy and high energy physics applications. They excel when tough requirements for lifetime, stability, precision and force are paramount. The extreme reliability makes them ideal for applications in difficult-to-access internals of instruments, where nanometer-realm adjustment and/or vibration cancellation are required. To promote long lifetime, the PiezoWalk controller can reduce the operating voltage on the piezo elements to zero at any position without affecting the full holding force (up to 800N, 177 lbs).
The piezoceramic clamping and shear elements act directly on a moving runner coupled to the load. For maximum velocity, and long distance movements, the runner can be driven in full step mode. Extremely uniform motion and constant velocity is achieved with the nanostepping mode. In addition to combining long travel ranges with piezo-class precision, NEXLINE PiezoWalk drives also offer a high-dynamics analog operation mode (100s of Hz) over smaller distances (to 6µm).
N-216 linear motors come in two versions for open- or closed-loop operation, as well as in two different load configurations. Closed-loop versions are equipped with a linear encoder for direct position measurement of the moving runner. The encoder features 5nm resolution over the full travel range. In open-loop operation a positioning resolution to 30 picometers can be realized by use of the (high-dynamics) analog operation mode.