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This is an arcade rhythm game called DanceRush Stardom, a similar concept to Dance Dance Revolution, but the dance pad acts more like a large screen and tracks both feet.

DanceRush Stardom arcade game

Here is an example video of gameplay : DanceRush gameplay

I want to make a similar type of input device myself, but I'm unsure how this is built.

My current thought is that it may use a grid of load cells, because looking closely at the image (or video at 0:14,) you can see a 6x10 grid of components inside the pad. The video, however, shows the LEDs follow the position and shape of his feet pretty closely so there may be more than a grid of load cells used here because the grid would need to be much more dense to get that precision.

What components are used for pressure sensing in a dance pad like this?

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  • \$\begingroup\$ What make you think that pressure sensing is used? Do mobile phone touchscreens use pressure sensing? \$\endgroup\$
    – Andy aka
    Feb 4, 2023 at 15:09
  • \$\begingroup\$ I'd asked someone with some electrical engineering experience and he noticed the grid of white pieces inside the pad and thought it might've used load cells. If it is more like a giant touch screen, is there a type I could find that's built to withstand a person's weight? \$\endgroup\$
    – shrimp
    Feb 4, 2023 at 15:29
  • \$\begingroup\$ I doubt they are load cells, based on complexity and expense of the cells and associated analog circuitry. More likely simple on-off switches consisting of PCBs , a thin insulating pad with holes, and a conductive membrane, like cheaply constructed keypads. \$\endgroup\$ Feb 4, 2023 at 16:37
  • \$\begingroup\$ I have watched a few videos now, interesting stuff. There is a motion camera inside that follows your body and actually this makes sense because it knows when the user use their left and right foot. Remember that Asian/Chinese countries are a way ahead with this kind of tech because of surveilliance. This is not a cheap machine, it has very powerful hardware to do the calculations in real time. Maybe there is some IR involved to detect the dancefloor and size. Nothing special, only LEDs, drivers and very strong glass (?). Maybe a good example for Solar Roadways haha, theyfailed at strongness \$\endgroup\$
    – Codebeat
    May 1, 2023 at 5:59

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Let's list some possible sensing modalities and compare their practical characteristics:

  1. Load cells: Requires an analog circuit for each sensing element, A/D conversion. Cost is relatively high per sensor. Unlikely.
  2. Analog pressure sensor: Starts as an analog signal, requires A/D conversion. Cost relatively high per sensor. Unlikely.
  3. Pressure-actuated switch: immediate digital signal (though may require debouncing). Can be very low cost if constructed with a conductive membrane, insulator matrix, and PCB contacts (like low cost keypads/keyboards). Likely.
  4. Optical proximity sensor: detects reflection of an infrared beam. More expensive than pressure switches, but could be more rugged as the cover layer does not need to flex, but needs to be kept clean. An interesting option.
  5. Capacitive sensor: requires circuitry to detect changes in capacitance. Can be sturdy with no moving parts. But I doubt it will work with thick rubber soled shoes. Unlikely.
  6. Touchscreen, either capacitive or resistive: would not stand up to stomping, and very expensive. Very unlikely.
  7. Piezo sensor: detects shock, not steady pressure. Inexpensive. Watching the video, it looks like the lights stay on all the time the foot is on the platform, rather than only during the "strike" instant. Unlikely.

There may be more possibilities. You can differentiate between 3 and 4 by placing your hand over the surface without pressing down. An optical sensor will respond, a pressure-activated switch will not. You could also take a picture with your cellphone (don't stand on the platform) and see if there are infrared beams showing.

Come back and tell us what you find out!

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Glad to know I'm not the only one thinking about making a similar device.

The Knowns

DanceRush Stardom is a rhythm game which one uses their feet to tap notes. In addition to the standard Left foot and Right foot notes — which technically one can use any foot or body part while freestyling — there's also "DOWN" notes and "JUMP" notes.

In terms of the physical sensing devices for this game, There are some things I'm not sure about. But one thing I do know about is how the foot location sensing mechanism works. DanceRush uses a grid of infrared laser diodes and receivers located underneath the metal casings on the sides. As Mark Leavitt points out in a different answer, this optical sensing scheme allows for more accurate foot detection compared to load-cells. This reddit thread showcases these diodes' location using an IR camera. The official arcade cabinet manual also showcases the importance of cleaning and vacuuming near these sensors. Dust, dirt, and any sort of debris can cause false sensing events. Same with false detections from reflected infrared light from the sun or other sources.

DanceRush also has a built-in camera, which is used in premium play options which records you and can share via Bemani's webapp (site in japanese). More on that later.

The Lesser Well-Knowns

The following I'm not 100% confident about, but makes sense based on my observations.

In addition to the infrared laser grid, I believe pressure sensing (the 6x10 grid of load-cells that you've observed) are also used. My justification is because of the following:

  1. "DOWN" notes, which the tutorial tells you to push your legs downwards to hit and
  2. The downwards force gauge on the top left of the screen which responds accordingly to "DOWN" notes and general stepping.

I also suspect that full-body visual motion sensing is also used. This wiki page says that motion sensing similar to a Kinect is used, but it's citation is the DanceRush website and I can't seem to find a reference for specifically body motion sensing. However the previously mentioned reddit thread shows that several lasers being emitted from near the camera module and are projected towards the floor.

If body motion sensing was used, it most likely used for the following:

  1. "JUMP" notes which require you to physically jump up and off the floor. Empirically, I've also observed that I can still do "JUMP" notes while the infrared grid is having false detection issues due to dust.
  2. Locating the player's body is 3D space to approximate visual effects locations and size from the aforementioned premium play option which automatically uploads to social media of the player's choice. This is what that recorded video + vfx looks, notice how downwards and upwards vfx from "DOWN" and "JUMP" notes are adjusted accordingly to the player's location in 3d space..

I hope this helps!

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I work at an arcade and specialize in rhythm game maintenance. I can tell you for sure that this game uses no pressure sensing whatsoever. It uses whats known in Japanese amusement tech as a break beam array, which is a series of IR sensors arranged along an x and y axis.

It doesn't use pressure sensing because it doesn't need to, it simply needs to know if your foot is in a certain range of x and y locations.

ProbsNotJack stated that down notes require you to "push your foot down," this is just a confusing note of the tutorial, "down" just denotes squatting or any other body lowering action. There is a camera module above the screen and it's ir sensor is used for detecting downward motion, which is then indicated by the "down" meter on the upper left of the screen. The common confusion with this is caused by how frequently this sensor loses calibration, causing almost any movement to count as a down movement. The camera does indeed function similar to a kinect as it also uses ir for motion sensing and approximates human bodies. This is mostly for video effects, but the video mode is disabled in the US due to COPPA laws.

As for jumps, the break beam array also approximates the size of your feet as a rectangle. The area of these foot rectangles is used to define when a note is actually hit, if the area is above a certain value that counts as being "on" the pad. Conversely, if the area is below a certain value, that counts as being "off" the pad. This is Also why small debris can exist on the pad without detection, but causes issues when a player is also on the pad.

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  • \$\begingroup\$ Actually I'm curious, how does the pad degrade then? So the sensors just one by one start malfunctioning after a restart or? \$\endgroup\$ Apr 18 at 1:32

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