PoleFX livens up acrobatic dance with Raspberry Pi | The MagPi #123

The networking power of Raspberry Pi drives LED lights to liven up acrobatic dance routines. Lucy Hattersley gives PoleFX a twirl in the latest issue of The MagPi, out now.

Billing itself as the world’s most advanced dance pole, PoleFX uses thousands of LED lights embedded inside a network-connected pole. On the sidelines, a Raspberry Pi-powered network box is using OpenCV to image match videos and turn them into light-based visual animations.

polefx fitter stood in dance club showing off LED lit pole installation
The outer shell of the pole is made using extruded black polycarbonate tubes that allow light to shine through

“Our goal is to create functional pieces of art and embed show technology into new places,” explains Spencer Hochberg, inventor and owner of PoleFX.

Amongst the dazzle and display, it is easy to overlook the technical requirements of this build. The pole itself needs to be “structurally strong” explains Spencer, to withstand the dynamic moves of acrobats, “while protecting and displaying an array of thousands of integrated pixels.”

polefx inventor stoof in workshop
Maker Spencer Hochberg spent his teenage years inventing unicycle tricks with photography and videography as a side effect. He earned a degree in mechanical engineering from UCLA, and now works with small teams on live shows.

Those thousands of pixels create an LED screen inside the pole structure. “The pole acts as a canvas for digital art that complements the performer,” explains Spencer.

Networked light

Inside PoleFX sits a Raspberry Pi acting as the system’s content server and control interface. Each pole is connected to PoleFX via an Ethernet cable, and the poles receive frames of data “on-the-fly” from Raspberry Pi. 

The control surface is a local web interface. “We also support simple control using a USB keyboard, encoder with OLED display, as well as DMX [Digital Multiplex lighting controller],” Spencer tells us.

inside polefx box showing PCBs with Raspberry Pi mounted
Inside the PoleFX box is a custom ESP32-based board with an Ethernet interface. Each pole is connected to the board via an Ethernet cable which transmits the data to the LEDs

“Raspberry Pi made it easy for us to put a flexible, low-cost brain in the middle of our system. The giant community of users has made it easy to find tutorials to get started and configure everything,” he notes.

The low power requirements for Raspberry Pi were also a consideration, and the “huge amount of online resources” made it quick and painless to implement. 

close up of LED lit dance poles
The animated poles enable the dance to have an extra layer of expression while the dancers perform their routines

The current poles are powered using a Raspberry Pi 3 Model B, which is processing and sending frames out at 60 fps.

Pole design

The poles had to be specially designed and custom-built for purpose. The outer shell of the pole is made using “extruded black polycarbonate tubes.” Spencer tells us this material is “resistant to cracking and hides the LEDs.” They allow the light to shine through.

Inside the pole, 3D-printed parts are used to mount non-structural components, and an internal slip ring that enables the wire connections to spin as the pole rotates.

PoleFX is “mostly built from off the shelf components.” The main mounting plate inside is a custom PCB (printed circuit board), which is an “easy way to fabricate a mounting plate and simplifies the internal wiring.” The back panel of the enclosure where the ports are exposed is also a PCB, used only for mechanical and cosmetic qualities.

Smart software

The main code is written in Python and the patterns are encoded as H.264 video files. The video frames are read using OpenCV to sample the pixel values. “We then composite and make other post-processing adjustments before sending the pixel data out over the Ethernet network in multicast sACN/E1.31 packets,” Spencer reveals.

polefx box housing raspberry pi technology
The PoleFX box contains a Raspberry Pi and the ESP32 board, and connects to the poles via Ethernet cables

Raspberry Pi is configured as a wireless LAN hotspot that hosts an Open Stage Control server, so the user can connect to the network and load the control UI without having to install anything.

Apart from controlling dance poles, the content-server side of the project is generally useful for storing, generating, and playing back LED animations for a wide range of installations where a whole PC would be “overkill”, and “a microcontroller alone is too limited.”

An early motivation for building load-bearing, pixel-mapped poles was to then use them to build larger structures. “Touch-reactive LED handrails and jungle gyms may be just around the corner!”


AndrewS avatar

It’s like a super-sized version of one of Toby’s lightsabers! :)

Ashley Whittaker avatar

do *not* advise waving one of these around in combat, however.

Liz Upton avatar

Having waved one of the lightsabers around in combat, I’m not sure I’d recommend that, either; that’s a hell of a lever arm to whack people across the head with. (Sorry not sorry, Antonia.)

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