this is my first post and first week using an arduino.
I would like to make a device that can be placed on a surface and via a button start will measure the flatness of the surface its on and display and data log the results to SD/USB in .CSV format.
So far i have a NEMA17 stepper motor attached to a 1M long ballscrew and frame driving a carriage with a micro epsilon laser displacement sensor on it.
I would like this device to be battery powerd from a drill battery or a mounted rechargable.
The perfect solution would drive the stepper down the length of the ball screw data logging laser displacment Vs stepper position. when finished display on 3" screen the largest deviation in mm and at what point along the stepper axis it was recorded and also recording the data to a .CSV on SD or USB drive.
is this possable? I have watched some stepper tutorals but not found much on data logging a .CSV or how to program a display....
Any advice or input on hardware or software would be greatly appreciated.
james_p:
is this possable? I have watched some stepper tutorals but not found much on data logging a .CSV or how to program a display....
You seem to know how to measure flatness and it seems as if your question is really about how to collect data and save it on an SD Card so maybe a better Title to attract the attention of people who can help would be "How to collect data and save to an SD Card"
If you modify your Original Post you can change the Title
Seems you need to define what you actually mean by "flatness". Are you looking for flatness based on the opposite edges of the object? What about the other edges? Flatness needs a reference.
What is your plan to calibrate your device?
When I look for flatness, I place a straight edge across the material and look for light showing under the edge. What is it you are trying to accomplish?
What resolution, what accurazy do You need?
Remember that Your linear moving device, rails, rods, etc. must be, lets say, 10 times more precise than the accuracy You want to measure at that surface.
Paul_KD7HB:
Seems you need to define what you actually mean by "flatness". Are you looking for flatness based on the opposite edges of the object? What about the other edges? Flatness needs a reference.
What is your plan to calibrate your device?
Maybe flatness is the wrong word, parallel to the surmeasuring device.
I really need help with choosing hardware to do the job too many options, is there a small Arduino with a SD slot for the data logging? That will run off a high voltage.
james_p:
I really need help with choosing hardware to do the job too many options, is there a small Arduino with a SD slot for the data logging? That will run off a high voltage.
I had hoped that my Reply #1 would have prompted you to say whether you need help with the device for measuring the flatness or whether you only need advice about saving the data.
And in either (or both) case(s) it will help to provide a lot more information about what you are currently able (or not able) to do.
Paul_KD7HB:
Perhaps describing exactly what you want to do is better than trying to find a word that fits.
Then give some actual numbers for your requirements. Can't determine what works without know what the fit is.
Paul
Hi Paul,
So would like to measure the surface finish on a flash butt weld. by placing the measuring device over the weld spanning 500mm either side of the weld with 1 meter of rail and ball screw with carriage(5mm pitch) driven by NEMA17 stepper. the device will be be supported 5mm off the sample at each end of the screw.
the measuring device is a Micro epsilon-1220 11-30VDC supply, 10mm measuring range, Repeatability of < 3.7 µm, outputting 4-20mA into the Arduino logger.
as the carrage is driven down the 1m stroke the laser value will be saved every X distance (10mm to start).
if the sampe was perfect the data log would be 5mm laser reading along the whole stroke of the carriage, in real operation ona sample i would expect +-1mm deviation. what i would like to to output to a small display on the unit to show the largest positive and negitive deviations and at what positions along the strokes they were.
at this point the device could be removed sample ground down in correct place and then remeasured. The device needs to be portable hence the battery operation.
I have all the mechcanical items and have found some tutorials on data logging, steppers and LCD displays which i hope to combine into one processor. my question is what processor, LCD displays, SD Card slot,real time clock and stepper drive would be best for this and work togeather?
So would like to measure the surface finish on a flash butt weld. by placing the measuring device over the weld spanning 500mm either side of the weld with 1 meter of rail and ball screw with carriage(5mm pitch) driven by NEMA17 stepper. the device will be be supported 5mm off the sample at each end of the screw.
the measuring device is a Micro epsilon-1220 11-30VDC supply, 10mm measuring range, Repeatability of < 3.7 µm, outputting 4-20mA into the Arduino logger.
as the carrage is driven down the 1m stroke the laser value will be saved every X distance (10mm to start).
if the sampe was perfect the data log would be 5mm laser reading along the whole stroke of the carriage, in real operation ona sample i would expect +-1mm deviation. what i would like to to output to a small display on the unit to show the largest positive and negitive deviations and at what positions along the strokes they were.
at this point the device could be removed sample ground down in correct place and then remeasured. The device needs to be portable hence the battery operation.
I have all the mechcanical items and have found some tutorials on data logging, steppers and LCD displays which i hope to combine into one processor. my question is what processor, LCD displays, SD Card slot,real time clock and stepper drive would be best for this and work togeather?
Hope this makes more sence.
James
Yes, it does, James.
Add to your parts list two micro-switches, one to indicate the beginning of the pass, and the second to indicate the end of the pass.
Does the sensor power the 20 ma loop or will you have to supply the power? The 20ma can be converted to a voltage the Arduino can measure.
Pick any Arduino with an SD card capability, or add another board to give you that capability.
Except for the SD card, an Arduino nano would do the job.
For visual, what do you want to show?
For calibration, I guess a surface plate or similar will work.