hack a digitizer pen [** EDIT: PICS, 648K **]
Posted: Mon Oct 08, 2007 8:54 pm
EDIT:
so the mp200 arrived, and worked just fine with the x61t (no eraser, no pressure sensitivity; as expected)
and then it got its poor self vivisected....
the short version is: holding the pcb and 3 bits of the nib assembly together between my fingers (oh lordy that was tricky, maybe I should have just used cello tape hahaha) the pen does function properly but the length of the assembly seems prohibitive in mounting it to some sort of finger ring -- might as well leave the pen intact and glue it to a ring. if we knew what sort of circuit to construct (I suppose I could get out the multimeter and probe this sucker up) then manufacturing a smaller more convenient size would be possible.
here's the long version:
shot 1: pen intact (nib off-camera on the right side), button removed. you can see the button's switch, and two potentiometers. I imagine the pots are for fine tuning the coil's 2 states: button up (default state), button down (click).
http://tintar.com/mp200/pa130170.jpg
shot 2: coil that is at the tip of the pen (nib butts up against this, you'll see in next shots)
http://tintar.com/mp200/pa130173.jpg
shot 3: guts and all. I opened the pen by peeling away light grey plastic that was covering the back/clip end of the pen. eventually the dark grey end pulled loose and I was able to pull out the little pcb "tray" which seems mainly to consist of the 2 pots, bunch of smd resistors, and the aforementioned coil.
http://tintar.com/mp200/pa130177.jpg
shot 4: closer on the pcb package.
http://tintar.com/mp200/pa130178.jpg
shot 5: close up on the (cheap, non-replaceable!) nib. the nib slots into a little cylinder of black plastic, which in turn slots into a tiny rubber o-ring. I guess this allows a little "give" or physical feedback? it did not seem to make for pressure sensitivity, but I could be wrong. I imagine the ibm and higher quality 3rd party pens have much different construction of the nib.
http://tintar.com/mp200/pa130179.jpg
20 bucks spent, curiosity somewhat satisfied. hrm.
/EDIT
I've read that the x4 and x6 pens are compatible with each other's screens (altho not necessarily the actual storage slot) -- so an active digitizer pen from e.g. a usb tablet should also work yes?
so: assuming it is a wacom digitizer, there is a magnetic field resonantly coupled with the pen, i.e. it powers the pen and also reacts to it. correct?
so: what exactly is it in the pen? small coil? rfid tag? I am curious to try getting a cheap (wacom-compatible) digitizer pen and taking it apart, to get out the whatsis, and, say make a small ring (or other fastening method) to wear it on my fingertip. don't care particularly about the extra button function at this point, just the main simple pointing/tapping bit.
anyone tried something like this before? suggestions?
Note from Moderator: Thanks for the warning, but images should be < 50k.
so the mp200 arrived, and worked just fine with the x61t (no eraser, no pressure sensitivity; as expected)
and then it got its poor self vivisected....
the short version is: holding the pcb and 3 bits of the nib assembly together between my fingers (oh lordy that was tricky, maybe I should have just used cello tape hahaha) the pen does function properly but the length of the assembly seems prohibitive in mounting it to some sort of finger ring -- might as well leave the pen intact and glue it to a ring. if we knew what sort of circuit to construct (I suppose I could get out the multimeter and probe this sucker up) then manufacturing a smaller more convenient size would be possible.
here's the long version:
shot 1: pen intact (nib off-camera on the right side), button removed. you can see the button's switch, and two potentiometers. I imagine the pots are for fine tuning the coil's 2 states: button up (default state), button down (click).
http://tintar.com/mp200/pa130170.jpg
shot 2: coil that is at the tip of the pen (nib butts up against this, you'll see in next shots)
http://tintar.com/mp200/pa130173.jpg
shot 3: guts and all. I opened the pen by peeling away light grey plastic that was covering the back/clip end of the pen. eventually the dark grey end pulled loose and I was able to pull out the little pcb "tray" which seems mainly to consist of the 2 pots, bunch of smd resistors, and the aforementioned coil.
http://tintar.com/mp200/pa130177.jpg
shot 4: closer on the pcb package.
http://tintar.com/mp200/pa130178.jpg
shot 5: close up on the (cheap, non-replaceable!) nib. the nib slots into a little cylinder of black plastic, which in turn slots into a tiny rubber o-ring. I guess this allows a little "give" or physical feedback? it did not seem to make for pressure sensitivity, but I could be wrong. I imagine the ibm and higher quality 3rd party pens have much different construction of the nib.
http://tintar.com/mp200/pa130179.jpg
20 bucks spent, curiosity somewhat satisfied. hrm.
/EDIT
I've read that the x4 and x6 pens are compatible with each other's screens (altho not necessarily the actual storage slot) -- so an active digitizer pen from e.g. a usb tablet should also work yes?
so: assuming it is a wacom digitizer, there is a magnetic field resonantly coupled with the pen, i.e. it powers the pen and also reacts to it. correct?
so: what exactly is it in the pen? small coil? rfid tag? I am curious to try getting a cheap (wacom-compatible) digitizer pen and taking it apart, to get out the whatsis, and, say make a small ring (or other fastening method) to wear it on my fingertip. don't care particularly about the extra button function at this point, just the main simple pointing/tapping bit.
anyone tried something like this before? suggestions?
Note from Moderator: Thanks for the warning, but images should be < 50k.