Refreshable Braille display

[Ghfggjvhjfh]

Hi, I’m have difficulties with my project. My project from your website is the refreshable braille display. I think that the problem is how I placed the jumper cables and other stuff on the breadboard. I did try following the picture exactly on the site. My project is due almost next week. Please reply as soon as you can and I’ll try to send a picture of the breadboard.


Moderator note: https://www.sciencebuddies.org/science- ... le-display

[DauntlessDog12]

Hi there,

In the photos that you've sent, all of the wiring more or less looks correct. You can double-check each of the transistors to make sure that the wires line up together in rows. One of the main problems may be that you need a power supply/oscillator that can provide 12V to the solenoids. Since the solenoids are rated for 12V, they need that much voltage in order to enact some action that you want for the Braille display. Hope this helps.

[bfinio]

Hi, a few things about your circuit:

1. As DauntlessDog pointed out, this project requires an external 12V power supply for the solenoids. From what I can see in your picture, you are powering the entire circuit using 5V from the Arduino, which will not be enough for the solenoids linked in the project's materials list (it would be OK if you bougth different solenoids that only require 5V).
2. Assuming you add an external 12V power supply as shown in the project, make sure you REMOVE the brown jumper wire that is currently connecting the two positive power buses on the breadboard. That would create a short circuit between 12V and 5V, possibly damaging your Arduino.
3. Make sure you ADD a jumper wire connecting the two ground (-) buses on your breadboard. The entire circuit will need a common ground.
4. Several of your diodes are backwards. The direction the gray stripe on the diode is facing matters. Again, see Figure 4 in the procedure. All of the gray stripes should be facing away from the MOSFETs, toward the power bus. But, fixing this alone won't matter if you still don't have a 12V power supply.

Hope that helps, please let us know if you have more questions.

-Ben (project author)

[BransonClearwater]

Check each jumper matches the diagram. Ensure components orient correctly and connections are secure.