Posted to News on 4th Oct 2009, 15:53
Module reduces the effects of machine frame motion
Aerotech's new ETM (Enhanced Throughput Module) combines sensor-measured micro-displacement and a user-friendly interface that identifies and helps to reduce unwanted machine base and frame motion in high-precision, high-performance positioning systems. By optimising point-to-point move settling times and minimising dynamic position errors for high-speed contouring, the ETM allows high- and ultra-high-resolution positioning systems to achieve improved throughput and enhanced parts quality.
Each ETM includes a very high resolution sensor that is simply mounted to the positioning system base or frame in line with the axis of motion being corrected. When used with Aerotech's Soloist, Ensemble or A3200 controllers, the ETM software works with the optional Dynamic Controls Toolbox to provide setup and monitoring screens that analyse unwanted frame motion during critical moves and plots position error vs time to a GUI. The Dynamic Controls Toolbox includes a range of tools to improve move and settle times and contouring performance, thereby greatly reducing the effects of machine frame motion. Measured improvement in settling times by as much as 20 per cent has been recorded.
During moves in any positioning system, the machine frame responds with oscillations that can extend over hundreds of milliseconds. Fine positioning or high-dynamic motion require that the oscillation subsides below the system resolution before completing the move and beginning the next motion. A consequence of this factor is that some systems never achieve desired accuracy if called upon to complete moves too quickly, or throughput is slowed considerably if the machine frame oscillations are excessive. While the most appropriate solution to these problems may be an optimised frame and machine base (such as an Aerotech-designed granite structure), in many cases this is either impractical or prohibitively expensive. Furthermore, for ultimate precision and high throughput, even these structures can be improved with the ETM.
The ETM is available in two versions - a standard version for high-performance motion systems and an ultra-high-resolution version for the most demanding applications. The convenient low-profile package size of the ETM, with a footprint of just 85mm x 70mm is easily built into new applications, and existing Aerotech motion systems across all current Aerotech controller platforms can also benefit from retrofitting to get faster production throughput or improve parts quality.
