No arc reduction / Improvement of quadrant protrusion

Means and verification examples for improving quadrant protrusions and circularity accuracy.

Here are some representative measurement examples using actual machines. It is a precision multi-axis machine controlled at a 10nm level. The reduction of the radius in normal arc interpolation is improved by a high position loop gain and pre-interpolation acceleration/deceleration. Furthermore, in high-precision arcs, quadrant protrusions also become an issue, but this is improved by linear motors. Measurement of roundness accuracy can be easily performed using Techno's motion controller tool, TPC logging, and analysis software such as Excel. Various tests can be conducted in a short time by changing the operating and control conditions. For more details, please contact us.

basic information

【Measurement Example】 ○Normal Arc →Operating Conditions Position Unit: 1p = 10nm Arc Radius: R = 10000000 (100mm) Speed: F = 5×10^7 pps (500mm/s) →Control Conditions Linear Interpolation Acceleration/Deceleration Time Constant = 50msec Position Loop Gain = 160 (r/s) →Results Arc Reduction: 50000p (0.5mm) The arc reduction is significant, making further evaluation difficult. Accuracy Judgment Scale: 70000p (700µm) →Since normal acceleration/deceleration occurs after interpolation, arc reduction occurs. ○Arc with Pre-Interpolation Acceleration/Deceleration →Operating Conditions Same as above →Control Conditions Linear Interpolation Acceleration/Deceleration Time Constant = 0msec Position Loop Gain = 160 (r/s) Pre-Interpolation Acceleration/Deceleration = 50msec →Results Arc Reduction: Almost none (good) Arc Accuracy: High precision with an error of less than 1μm Quadrant Projection: 400p (4μm) Accuracy Judgment Scale: 500p (5μm) →With pre-interpolation acceleration/deceleration, arc reduction has been eliminated. Please note that the evaluation scale has improved by 140 times between Measurement Examples 1 and 2. ●For more details, please contact us.