3rd-order multi-axis look-ahead trajectory algorithm smooths driven motion

September 28, 2014 // By Graham Prophet
ACS Motion Control (Israel) has introduced an advanced 3rd order look-ahead trajectory generation algorithm that optimises the efficiency of motion control systems. Increasing acceleration, smoothness and velocity, while minimising motion-induced vibrations and disturbances, the 3rd order look-ahead trajectory generation maximises any system's throughput.

Maximum velocity and acceleration limits for each motion axis are set according to stage parameters, and maximum jerk (jerk: rate of change of acceleration, 2nd derivative of velocity) can be optimised by each user. Any of these parameters can be changed on the fly during motion for further control and optimisation. The motion controller constructs an optimally smooth multi-axis trajectory through the user-defined path, based on independent axis parameters.

The graphs show 2-axis (green/blue) values of jerk in a laser cutting machine, the background chart showing a standard 2nd-order look-ahead algorithm with large spikes, and the foreground, the outcome of the 3rd-order algorithm.

“A 2nd order look-ahead trajectory generation algorithm, which only places limits on velocity and acceleration, can result in significant jerk and vibration in the system, reducing the throughput of the equipment. The more advanced 3rd order look-ahead trajectory generation, which limits jerk, provides much smoother motion and reduces vibration,” said Jason Goerges, General Manager at ACS Motion Control.

The 3rd order look-ahead trajectory generation algorithm is suitable for a wide range of motion control applications including smartphone PCB/glass laser cutting, via hole laser drilling, LED/OLED inkjet printing, semiconductor wafer scribing, precision conformal coating, precision automated fluid dispensing, precision additive / 3D printing. The 3rd order look-ahead trajectory generation algorithm can be implemented with any ACS Motion Control product: an international manufacturer of advanced multi-axis motion controllers, machine controllers and integrated control modules, ACS provides standard and custom products.

ACS; www.acsmotioncontrol.com