American engineers have created a robot that applies metal conductive paths to walls for interactive panels. For example, with its help, the developers applied a touch-sensitive musical synthesizer and a coffee machine control panel to the wall. The authors have published an article in The Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies (IMWUT) magazine, as well as self-build instructions on GitHub.
We have talked more than once about projects in which engineers make walls, tables or other household surfaces interactive. One of the most popular methods for this involves applying metal elements to the wall to act as touch panels. For example, last year, engineers created a program in which the user creates the interface he needs, and then receives stencils with which the interface can be sprayed onto the wall with paint on his own.
Developers led by HyunJoo Oh of the Georgia Institute of Technology have increased the automation of this approach by creating a robot that applies shaped paths to a wall.
The engineers chose a simple and popular pendant plotter design. It consists of a robot suspended on two cables – in this case, the drive belts. On the one hand, each cable is fixed on the robot, and on the other, it is attached to the wall with glue or in another way. The principle of operation of such a mechanism is very simple: the motors at the attachment points pull the cables and thereby control the movement of the robot horizontally and vertically, moving it to the desired point.
The robot itself has three compartments into which you can load “pens” with ink: you can use only one view at a time, but the platform can rotate, so the robot can first draw conducting paths, and draw a drawing or instructions on top or next to it with ordinary ink. The robot is made on the basis of available components, such as the Arduino board, and most of the parts are 3D printed, so you can assemble it yourself: documentation, code and files for the interfaces are published on GitHub.
To create the interfaces, the developers wrote a simple application in which you can draw the desired diagram and get the instruction files for the robot. As an example, the authors painted several interactive panels on the wall, including a synthesizer with keys and buttons for setting, as well as a control panel for a coffee machine. After the robot has drawn the conductive tracks, a simple microcontroller must be attached to them (the authors used ESP32). In the case of the coffee machine, they also used the IFTTT service, which takes a command from the ESP32 and sends it to the coffee machine.
The construction of a hanging plotter has already been used for drawing on walls, however, not with metallic ink, but with ordinary ink. In 2018, the Scribit company raised money on Kickstarter for the production of such a robot, however, it was not able to establish production, judging by customer reviews.