By: darioringach
D: Motion Control and Knobby, Uncategorized, , ,

Installing knobby tablet

Before you start you will need an android tablet and a wireless router in the Lab.

I have a Samsung Galaxy Tab E and an Airport Express, but other tablets and routers should work as well.

To install knobby tablet follow the following steps:

  1. Download knobby tablet from the Google Play store.
  2. Download and install the latest version of Scanbox (as always keep a copy of previous version).
  3. Download and install PyOSC.  To install, open a terminal, go to the directory where you uncompressed PyOSC, and type “python setup.py install”.
  4. Copy over the settings in the scanbox_config.m file.
  5. Connect the computer running Scanbox to your local wireless router
  6. Open a terminal window and check the IP assigned to the computer by typing ifconfig.
  7. Set the tri_knob configuration variable in scanbox_config.m to a string that contains the IP address, for example, ‘164.34.123.31’.
  8. Start Scanbox.  You should also get a command window with the knobby tablet console.  We will check if commands from the tablet are received there.
  9. Open knobby tablet on your Android.  You will likely get a message saying that the default IP is invalid.  Click Ok.
  10. Click on the IP number button.  A keyboard will show up.  Enter the IP number you found above.  However, make sure that every section has 3 digits (use zeros if necessary).  Thus, in the example above, one would type 164.034.123.031
  11. If the tablet cannot connect, you will see an “Invalid IP” message.  Otherwise, you should be ready to go.  The IP gets stored in the tablet, so launching knobby tablet later will retrieve it.
  12. Remove the objective from the microscope (just in case).
  13. Make sure the scope is roughly in the middle of its travel for all axes.
  14. Click the “Normal” button on the tablet.  Do you see a message printed on the knobby console?  If so, communication is working Ok.  If not, something is wrong.  Contact me.
  15. Stand close to the motor box so you can quickly power it off if something does not work as expected.
  16.  Now touch the button corresponding to the Z axis on the red region.  The z-axis will begin to move so long as you keep touching it.  The speed of movement will be faster the farther away you are from the center.  Slide your finger left and right, the speed will change and it should reverse if you move over to the blue side.
  17. Test the other axes.screenshot_20161112-150708
  18. Touch “Velocity” to switch to velocity mode.
  19. Warning: the microscope will move fast now…  Touch the red or blue areas of each button.  The microscope will move at a fast/fixed speed so long as you keep touching the area.  It will stop when you release.
  20. Store/Recall buttons work as before
  21. Go back and try the Fine and Super-Fine modes.
  22. Play with it for a while and install the objective back after you familiarize yourself with the tablet interface and everything seems to be working Ok.
  23. You can minimize the knobby console once testing is done (I will do this automatically in future versions).
  24. The green buttons on the side lock the button area (bottom) or knob area (top).  So if you are acquiring data and don’t want to have a situation where people touch the tablet by mistake and move the microscope you can use the buttons to lock them.  Touching them again will unlock.
  25. Make sure you open knobby on your tablet  after you start Scanbox.

If you run into problems don’t hesitate to write.