5 ms·

Tiny pinpoint holes, blow air through them. Could you adjust the size of the holes and the flow of the air so you could feel them distinctly? If so, they could

Tiny pinpoint holes, blow air through them. Could you adjust the size of the holes and the flow of the air so you could feel them distinctly? If so, they could be backed by much larger, far away, valves without the mechanical parts needing to be so fine and precise. You only need to feel something, there doesn't need to be anything there - is it possible to have a voltage or capacitance charge or signal at a point which feels like a presence? "A smooth surface which feels lumpy" seems intuitively unlikely but stranger things have happened.

ajb 3y ago
Yes, I was wondering if something could be done using 3d printed fluidic logic. If so then the entire thing could have no solid moving parts, and just be one big 3d print, except: (maybe) a single big rubber membrane in which dots are raised by fluid pressure. Plus of course the fluid pressure source; and the valves to interface the device to electronics, to input the display data. Otherwise it could be a big shift register in fluidic logic with an amplifier at each bit to output to each dot. The difficulty with fluidic logic is that the devices from the original flowering of the field don't work at the low Reynolds numbers found in smaller devices. Maybe something from the new micro fluidic field would work, but I don't know if they can control sufficient pressure to be felt, or to raise a rubber membrane.
buu700 3y ago
"A smooth surface which feels lumpy" seems intuitively unlikely but stranger things have happened. I wonder how well it would work if you did something similar to Force Touch, but instead of one uniform trackpad it were separated into a matrix of small dots.
contingencies 3y ago
Yes, you can do that but you still need a cheap valve with a size ideally smaller than one dowel pin 'cell' at standard braille densities. AFAIK this does not exist commercially, if it does it would be cost prohibitive, and therefore would need to be designed in some unknown manner focused on low fabrication cost. Since most valves operate based upon electromagnetism (solenoid-driven) you also have an electrical control problem. All in all, not an attractive solution path.
- jodrellblank 3y ago
  The reason for suggesting that is because it wouldn't need tiny expensive custom delicate valves; connect the pinhole to a funnel which gets wider like the horns on this siren: https://stall.net/victorysiren/photo-pages/cars2/images/5SG-CHR4.JPG https://stall.net/victorysiren/photo-pages/cars2/images/5SG-... then you can use whatever large, cheap, widely spaced, easy to access, easy to maintain, valves you can find. The trade would be size, noise, and power, but the gain would be easy to build, mass produced parts, easy to repair, large and solid and relatively reliable.
  - contingencies 3y ago
    Most valves are actuated by solenoids which use a lot of power. An array of them is not only physically huge but will exceed USB power availability at a count of one or two valves and you need many per braille block. Worse, you generally need to actuate huge numbers of them simultaneously. This approach is therefore difficult to consider for a real world deployment.
    - jodrellblank 3y ago
      The top comment on this thread by gostsamo is "As someone blind, my two pens [pence?] are that noise, power consumption, and fragility are things that could be compromised to a large degree." How many do you consider 'huge numbers'? There's another comment saying a Braille cell is 8 dots, and if you average changing half of the dots each time to change state, you could barely get into double digits to keep ahead of the fingers. > "This approach is therefore difficult to consider for a real world deployment." It only had 10 seconds of thought; I just skim read the article which was all about mechanical actuation and the difficulty of making so many small and precise and reliable actuators cheaply enough, and wondered about options that didn't require that part. Air, electric current (e.g. the vibration felt in a pot on an induction hob vibrating some loose rods without having to actually lift them), or a one-finger glove where there is only a few actuators and they change as the finger slides over a table, or no actuators - a design like the way a CRT screen has a scanning electron beam activating each pixel, although I have no ideas how a design like that could activate Braille dots.

ajb 3y ago

Yes, I was wondering if something could be done using 3d printed fluidic logic. If so then the entire thing could have no solid moving parts, and just be one big 3d print, except: (maybe) a single big rubber membrane in which dots are raised by fluid pressure. Plus of course the fluid pressure source; and the valves to interface the device to electronics, to input the display data. Otherwise it could be a big shift register in fluidic logic with an amplifier at each bit to output to each dot. The difficulty with fluidic logic is that the devices from the original flowering of the field don't work at the low Reynolds numbers found in smaller devices. Maybe something from the new micro fluidic field would work, but I don't know if they can control sufficient pressure to be felt, or to raise a rubber membrane.

buu700 3y ago

"A smooth surface which feels lumpy" seems intuitively unlikely but stranger things have happened. I wonder how well it would work if you did something similar to Force Touch, but instead of one uniform trackpad it were separated into a matrix of small dots.

contingencies 3y ago

Yes, you can do that but you still need a cheap valve with a size ideally smaller than one dowel pin 'cell' at standard braille densities. AFAIK this does not exist commercially, if it does it would be cost prohibitive, and therefore would need to be designed in some unknown manner focused on low fabrication cost. Since most valves operate based upon electromagnetism (solenoid-driven) you also have an electrical control problem. All in all, not an attractive solution path.

jodrellblank 3y ago
The reason for suggesting that is because it wouldn't need tiny expensive custom delicate valves; connect the pinhole to a funnel which gets wider like the horns on this siren: https://stall.net/victorysiren/photo-pages/cars2/images/5SG-CHR4.JPG https://stall.net/victorysiren/photo-pages/cars2/images/5SG-... then you can use whatever large, cheap, widely spaced, easy to access, easy to maintain, valves you can find. The trade would be size, noise, and power, but the gain would be easy to build, mass produced parts, easy to repair, large and solid and relatively reliable.
- contingencies 3y ago
  Most valves are actuated by solenoids which use a lot of power. An array of them is not only physically huge but will exceed USB power availability at a count of one or two valves and you need many per braille block. Worse, you generally need to actuate huge numbers of them simultaneously. This approach is therefore difficult to consider for a real world deployment.
  - jodrellblank 3y ago
    The top comment on this thread by gostsamo is "As someone blind, my two pens [pence?] are that noise, power consumption, and fragility are things that could be compromised to a large degree." How many do you consider 'huge numbers'? There's another comment saying a Braille cell is 8 dots, and if you average changing half of the dots each time to change state, you could barely get into double digits to keep ahead of the fingers. > "This approach is therefore difficult to consider for a real world deployment." It only had 10 seconds of thought; I just skim read the article which was all about mechanical actuation and the difficulty of making so many small and precise and reliable actuators cheaply enough, and wondered about options that didn't require that part. Air, electric current (e.g. the vibration felt in a pot on an induction hob vibrating some loose rods without having to actually lift them), or a one-finger glove where there is only a few actuators and they change as the finger slides over a table, or no actuators - a design like the way a CRT screen has a scanning electron beam activating each pixel, although I have no ideas how a design like that could activate Braille dots.