Close

Pin actuation looks promising!

A project log for Refreshable Braille Display

A cost effective way to make a refreshable braille display

vijayVijay 04/29/2016 at 12:062 Comments

I couldn't get the motors I need, but was able to source a 6mm dia version (double the size I need) to see if the cam+follower thing would work, I just couldn't take the suspense of not knowing!

I was too lazy to CAD anything for the test, I had to know IMMEDIATELY!

so I ground the weight to a shape I wanted, got my friends iPhone to record in slow mo, and it looks promising!
I can't be 100% sure the final would work, since the actual motors I need to use are smaller, but I feel it's got a fighting chance!

I also realised I'm using 2 simple machines, a lever and a ramp, and it oddly satisfies me for some reason.

Inferences:
- there is only a ~0.5mm lift required at the cam follower to achieve the required lift at the pin.
Hence, a shallower angle on the cam, would make it even more easier to lift the pin ( because of the shallower slope of the ramp of the cam )


I contacted sales at Precision Microdrives about sponsoring their motor, https://pmdri.zendesk.com/attachments/token/koNuCT5zcZuO6kQC6E56rh040/?name=303-103-datasheet.pdf

They got back saying they won't lower the MOQ or the price :( gotta figure out another way of getting my hands on them, or else try and change the design to use 4mm dia motors from china ( highly unlikely they will fit the requirement due to the size constraint)


A big thanks to @Anool Mahidharia for the article on Hackaday today!
http://hackaday.com/2016/04/28/refreshable-braille-display-and-braille-keyboard/










Discussions

Yann Guidon / YGDES wrote 04/29/2016 at 15:08 point

Congrats for your first tests !

+1 for changing the angle as well. I'm now a bit worried about the heat generated by a motor that is stuck in "high" position because it's not designed for high torque.

And IMHO it's better, in the first prototype, to have a coarser/larger array, than no array at all. Use what you can easily get so others can follow you, then improve and optimise when it works :-)

I'm curious to see a comparison with torus/coils. Will the magnetic fields interact with the neighbours ?

  Are you sure? yes | no

Vijay wrote 05/02/2016 at 07:39 point

I found another supplier from china  http://www.alibaba.com/product-detail/micro-hollow-cup-motor-vibration-all_60400026336.html?spm=a2700.7724838.0.0.oMP2Y4

If this doesn't work out, then ill use 4mm motors and make the pins coarser.

  Are you sure? yes | no