Looking to make a floor button to trigger when you stand on it

[smdftw]

Hi Guys,

 

I'm currently making an interactive film project. The idea is that I will put a sticker or shaped doormat on the floor, and when someone steps on that, a video starts playing on a screen. 

 

I need some help on how to build that kind of trigger.

Can someone give me some advice on how to approach something like this? I was thinking about some arduino stuff that can trigger a simple keypress. 

I've tried some google-ing but without luck!

 

 

[samcool55]

You can always take a cheap mouse, take it apart, put the sensor on the play button and re-wire the left mouseclick to the pressure thing you have.

Someone steps on it, triggers the click and it plays

 

0 programming required, but ghetto AF. If you only need it to work for like a few times it's good enough tho.

[smdftw]

I was thinking about something like that as well. But  I think it needs to be a little more professional. It will be displayed at a convention so potentially hundreds of people will need to be able to step on it. Also I don't have something like a pressure sensitive pad, as I don't know where to start. Can you point me in the right direction on what I would need?

[Rolling Potatoe]

Id do it mostly like samcool55 recommended.

Build a plattfform with another plattform held up by springs or foam so it can be pushed down a few mm,

mount a switch (something like an arcade button, cost like 1-2$) that will be pressed when someone steps on the plattform.

Connect the switch to your pc with something like this http://www.ebay.de/itm/Zero-Delay-Game-Controller-USB-to-Joystick-for-MAME-Raspberry-Pi-1-2-3-AC425-/272843252457?hash=item3f86b9a2e9:g:MfsAAOSw881ZttLN and use something like auto hotkey to make it start your video.

[Dujith]

For detecting when someone steps on a doormat i would not reinvent the wheel  

You can get a cheap large one from anywhere. 

 

[mariushm]

There's all kinds of switches manufactured .. momentary switches, emergency stop switches, rocker switches, all kinds.

Here's some links to browse and use your imagination :

 

Snap action, Limit switches (used typically to detect if something has reached the end of something or as emergency stop, or sometimes to detect if doors are opened completely or not ) : https://www.digikey.com/products/en/switches/snap-action-limit-switches/198

^ use actuator type and features column to filter to your needs

 

Magnetic switches, reed switches : https://www.digikey.com/products/en/switches/magnetic-reed-switches/193

You put the switch on the top lid and a magnet all the way to the bottom of the box. When someone steps on the thing, the top goes down and gets close to the magnet so the switch triggers ... when the magnet goes far enough (user steps off and springs lift the top)

 

You may also get it working with regular tactile switches, there's all kinds of other categories out there, see https://www.digikey.com/products/en/switches/15?newproducts=1

 

As for interaction with computer, the absolute easiest would be to get the cheapest usb mouse, desolder one of the mouse buttons and solder the wires from the switch to the mouse button .. while foot pedal is pressed, the mouse button will be pressed. 

It's cheapest but crappiest as well, because the mouse button being pressed will affect windows applications and your application perhaps.

 

Another cheap way would be a 1-2$ microcontroller with USB functionality (pic18f for example) ... you can quickly program it to be recognized as a generic usb keyboard, and make it send some combination of keys typically not typed by people .. your application would detect the key combination and do stuff.

 

A simpler way would be to use an arduino and some serial to usb adapter (if your computer doesn't have any serial ports) .. each time the button is pressed arduino sends through serial port that the button is pressed, and sends "button no longer pressed" when the switch is off. You would need to have a custom application that would listen on the serial port and read the incoming messages (very easy but requires custom programming, it's not like reading keys in windows.

 

Note that there's also such things as load cells , which can measure the actual weight or trigger only when enough weight is on them (or pressure) : https://www.digikey.com/short/q7dqbv

A bit overkill for a foot switch.

[Hackentosher]

I remember reading about making pressure plates in The Dangerous Book for Boys when I was like 9. You can do it with some aluminum foil, some cardboard, and a sponge, but I think the mouse idea would be easier to interface with the computer.

[samcool55]

I guess a makey makey could also work with a pressure pad. Not cheap tho (50 bucks)

Or the makey makey go, only 20 bucks and should give you the functionality you need.

Programming in AHK might be required tho. Don't know, i'm not that familiar with it.

[Ahoy Hoy]

14 hours ago, smdftw said:

Hi Guys,

 

I'm currently making an interactive film project. The idea is that I will put a sticker or shaped doormat on the floor, and when someone steps on that, a video starts playing on a screen. 

 

I need some help on how to build that kind of trigger.

Can someone give me some advice on how to approach something like this? I was thinking about some arduino stuff that can trigger a simple keypress. 

I've tried some google-ing but without luck!

 

 

Midi signals is all you need.