I named the project Bigfoot because the foot pedal itself is modeled on my own oversized right foot.

The pedal is made to be comfortable.  The usual pedals are too high and require me to either bend my foot upwards, or else hold my foot and leg in a sort of hover above the pedal.

The Bigfoot pedal is made to support my foot so that I can work the pedal with just the ball of my foot.

Let's take a look at Bigfoot's big foot:

That's a beech wood foot with a "heel" and a "sole" to support it.  There's a layer of thick felt underneath it all to keep it from scratching the floor.

The cable has three conductors for the signals and a steel cable to keep it from breaking if you pull on it hard - the steel cable is anchored in the connector and in the pedal. The connector is an Amphenol 3-pin screw in model.  It is really overkill and cost way more  than is reasonable for a personal project.

The actual working part of Bigfoot's big foot is that black pedal.  It is a Hall effect accelerator pedal like this one on Amazon.  It has three connections: +5V, ground, signal.  The signal output is a voltage between about 0.2 and 4.8V that is linearly proportional to how far you have pressed it.  0.2V = all the way up, 4.8V all the way down.  It is as easy to read with the Arduino as a potentiometer would be, but it won't wear out the way a potentiometer would.  The hinges or the spring might give out, but I'm pretty sure the sensor won't.

The pedal appearance doesn't quite match that of the sewing machine I use it with.  My Adler 8 sits on a shellacked box made of oak.  Bigfoot's foot is made of beech wood stained walnut with a coat of hardwood floor sealant instead of shellac.  I'd have made it of oak, but I didn't have any oak scraps left - I'd have had to buy about 30 Euros worth of wood for just that little piece.  I used hardwood floor sealant on it because I expect it will be kicked around quite a bit - shellac looks good but it isn't tough enough.

The "design" is literally just  a tracing of my foot that I scanned into the computer.  I drew cutouts and mounting holes for the pedal using Inkscape then used the printed template to do the woodworking.