Thank for the replays.
@roydm
The measurement data shows, if a direction is changes in XY plane, there is always a 10-20µm jump in Z direction. Where as there was no movement along z axis.
actually I do not know if it is possible to miss a pulse.
Counter board calculate the position with two...
Hello,
I am measuring a position using linear encoders by Heidenhain. The encoders output is 1Vpp which is then interpolated (200 times) to get TTL signal (10 KHz). National instrument counter board PCI 6602 is then used to calculate the position. Matlab is used to acquire and save the position...
Thanks for the reply,
Yes some manufacturers claim 1µm resolution. But it may be the ideal case with PSD in stationary condition.
If some body may have experience with practically realizing some position measurement application using a PSD, that would be great information for me.
Thanks for the reply.
I am currently thinking if I should try to develop thins application or not. The hardware and signal configuration is not fixed at this point.
The things which I can fix now is:
about 9x9 size PSD
This is correct that that spot size, relative size of spot to PSD, signal...
Hello,
I want to use a PSD (Position Sensitive Device) and a laser beam for the position measurement. Laser beam will be stationary and PSD will be moving (50 mm/s).
PSD’s are available in different sizes (4 x 4 to 20 x 20) mm. Bigger the size of the PSD, less the resolution and accuracy. It...
Maximum allowed frequency for 200 times interpolation (currently set) mensioned in data sheet is 12.5 kHz. The current input frequency which I have been trying id from 10-50 KHz. I do not have possibility to test with input signal below 10 KHz.
It seems violating the allowable input frequency...
The radius used is 150 mm. I think too that the encoders are functioning right.
I just thought about the possibility that the input frequency of 50 KHz might be high for the interpolator (200 times interpolation). May be I should try to reduce the interpolation factor (not sure).
could it be a...
Hello,
I am trying to measure the position from 2 linear encoders (XY Plance).
My hardware setup is such as:
2 Encoders (Heidenhain) provide sine wave position signal (signal period 2 µm, frequency appx. 50KHz ). Signal is then digitized and interpolated (Sine wave to TTL, 200 times) using an...
Actually I want to simply read CNC file, extruct x y z vales and save into a matrice in matlab. Similarly I would like to do inverse. Thus i may need simple functions (no tool path calculation).
thanks
hello
Sorry I did not explain the deviations.
A milling machine has a certain accuracy lever (finishing tolerance). This is due to the dynamic and static errors in a milling machine. More the dynamic and static errors are in a milling machine less is the accuracy. In other words more would be...
Hello,
I am planned to calculate the deviations in reference and measures tool path of a milling machine (for offline analysis in computer).
Reference path is generated using reference CNC code and measured path is measured using sensors on TCP (tool centre point)
Both paths may looks like...
Hello
I am planned make an application using an optical linear encoder (Heidenhain).
Encoder (3 x sine) ---> Interpolation (3 x TTL )----> Counter board ---> Position
I want to test the application in simulation before going to real. For this I want to generate the final position signal...
I am planning to implement a dynamic error compensation system for a CNC Milling Machine to improve its accuracy. Machine is controlled by Sinumeric 840 controller. The Real 3D-trajectory of the tool will be measures on line.
Tasks may include:
Conversion of NC-code (currently only G01)...
Hello,
This would be a position signal, an actual measure of tool of a milling machine along x axis. Similarly there will be position measure for y and z axis. This would give the real trajectory measure of a milling tool.
A reference path would be generated from provided NC Code in Simulink...
