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The pressing force of one button

Sclv

May 21, 2023
2
Joined
May 21, 2023
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Hello

Perhaps, for example, you are developing a keyboard. Not necessarily the same as the one I have from the pyramids. https://maker.pro/raspberry-pi/projects/mouse-keyboard-pyramids Any keypad. I see some people here are doing this.

Probably the first thing you need to know is that your device would be convenient not only for you, and with what effort someone else will have to press one button? How many newtons or pascals must be applied to make typing easy and comfortable? The exact value here is needed to calculate the spring force. Of course, you can try just pressing the button and measuring the force itself. This is a costly method and it does not give an answer to the result, how comfortable this or that effort is.

I decided to try a different path. I decided to use musicians whose experience in this area is the most studied. A piano performer spends about 200 kilocalories for one concert hour. The guitar player is a little under 160, but I decided that my keyboard is closer to the guitar. Five rows of pyramids are like five strings. The efficiency of muscle work ranges from 10% when lifting weights to 20-25 when riding a bicycle. I took 13% out of caution. The average typing speed per minute is 200 characters, and per hour 12,000, which is two-and-a-half sheets, and that’s roughly how it works out for me. When calculating, it turns out that there are about 7 joules (1.73 calories) per symbol. In my device, the force is applied from above, but the movement occurs in the horizontal plane. Multiplying by the cosine, I got a pressing force to calculate the springs of approximately 5 newtons. Of course, from this we also need to remove the resistance of the hollow plastic body of the key itself - the pyramid.

I wonder if anyone else has used a similar method before me?
 
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