Sharing ideas on manual servo optimization and adjustment

Conventional servo optimization and adjustment generally require the use of SERVO GUIDE software. For some customers who are not very familiar with the operation of the software or cannot perform online network adjustment on site, manual adjustment becomes more critical and practical. Here we provide ideas for manual servo optimization and adjustment.

1. Parameter confirmation

Before performing servo optimization, you need to confirm whether the basic system parameters are set reasonably. There are two common methods.

Method 1: Import standard parameters. (Standard parameter package can be obtained by contacting FANUC technical personnel) Method 2: Manually modify after the motor is initialized, follow the steps below:

① Set the following two parameters and then power off and restart No.2020 = motor code No.2000#1 = 0

② Refer to the parameters in the table for setting

2. Eliminate resonance

2.1 Three Elements of Filters

① Center frequency: The center frequency position of the filter, generally set at the frequency of the resonance point.

②The scope of application of bandwidth filter.

③ Damping: The degree of filter suppression, the value is 0-100. 0 means suppression to 0% of the original value,

The effect is the greatest; 100 means suppression to 100% of the original value, that is, no suppression

example:

2.2 Filter Bank

FANUC has the following 5 groups of commonly used HRV filters

4 sets of filter settings for common resonance points

Note: Because the value of filter 1 will become 0 when the motor is initialized, it is recommended to use filters 2-5 first.

2.3 Filter confirmation

Step 1: Select an axis and perform manual rapid movement at various magnifications to see if there is any vibration or abnormal noise. Step 2: If there is no abnormality in manual rapid movement, write a G01 program (under F500 and F2000) to execute it to see if there is any vibration or abnormal noise. Example: G01X500F500 G01X500F2000 If there is vibration and abnormal noise, fine-tune filters 3 and 4:

Adjustment method: Adjust the center frequency first, then adjust the damping (1) The center frequency moves about every 20Hz (2) The damping decreases every 10% (3) The bandwidth remains unchanged III. Rigidity improvement 3.1 Speed ​​gain After setting the filter, set the speed gain according to the following table No.2021 (basic gain): load inertia ratio; No.2335 (effective during cutting): HRV3 + speed gain ratio Depending on the machine model, set the No.2021 and No.2335 values ​​within the following ranges:

3.2 Position gain After setting the speed gain, adjust the position loop. Rapid traverse position gain: No.2178=3000; Cutting feed position gain: No.1825 (each axis needs to be set to the same value) Depending on the machine model, set the No.1825 value within the following range:

3.3 Gain confirmation steps Step 1: Select an axis and perform manual rapid movement at various magnifications to see if there is any vibration or abnormal noise. Step 2: If there is no abnormality in manual rapid movement, write a G01 program (under F500 and F2000) and execute it to see if there is any vibration or abnormal noise. Example: G01X500F500 G01X500F2000 Step 3: If there is still vibration, it is necessary to appropriately reduce the speed gain. Reduce the value of No.2335 by 50, but try not to be lower than the recommended lower limit.

Step 4: If vibration and abnormal noise still exist after reducing the gain, it is recommended to use SERVO GUIDE software for fine tuning and confirmation. If there is still no improvement, it may be affected by mechanical factors and the machinery needs to be checked. IV. Quadrant elimination 4.1 Adjustment steps for circular processing Step 1: Use a meter or laser interferometer to measure and correctly set the reverse clearance value No.1851 of each axis; Step 2: Perform trial processing of the arc and adjust parameters No.2048 and No.2071 according to the situation of the arc quadrant bulge

The degree of convexity of the arc quadrant is related to No.2048, and the width of the convexity is related to No.2071

Adjustment example:

5. Tapping Adjustment 5.1 Basic Parameter Setting To adjust rigid tapping, you must first set the basic parameters: Method 1: Import standard parameters (recommended) The standard parameters already include the basic parameters for tapping. If the standard parameters have been imported during debugging, you can proceed to the next step. Method 2: Set the parameters according to the attached table

5.2 Tapping error debugging

The system error of rigid tapping can be checked through diagnosis 453. To ensure the rigid tapping effect of the machine tool, it is necessary to ensure that the maximum tapping error of diagnosis No. 453 is within the range of the following table

If the diagnosis No.453 exceeds the value in the table above, the rigid tapping time constant No.5261~No.5264 can be appropriately increased, and the adjustment range is: 300~1500