Summary

Colorful circles are projected on the ground, and action occurs in the projected image when a person steps on it. Staff members operate controllers in accordance with the action of people, providing an experience as if the work is changing according to the people.

Purpose

• To create artwork to entertain guests for a projection mapping event at a university festival.

• To create interactive works.

Process

Development Policy

Based on last year's results, the concept of the work was decided as follows. (1) Colorful circles are projected on the ground, and (2) when people step on them, an action is triggered.

Methods for detecting human position include a laser range finder, depth sensor, and image processing. We considered creating interactive works using sensors but abandoned them for the following reasons.

• The production period was limited to three days.

• The venue was dark, and many people were moving around, so sensors could not be installed near the ground for visitor safety.

Instead, the operator will control the system manually according to the people's actions, providing an experience as if the images are changed according to the people's movements. In addition, by creating a special interface (controller) for this work and creating a system that allows movement to be added to the images with a button, the policy was designed to make it fun and easy for the operation staff to participate in the work.

System Configuration

Projected content was created in openFrameworks. The Arduino, the microcontroller in the controller, controls LEDs, reads button states, and communicates with an app on the laptop. The projector projects the openFrameworks execution screen.

Projected Contents

Two types of content were created: (1) a type in which circles disappear when people step on them, and (2) a type in which ripples spread. Transitions between scenes can be made with a keyboard on the laptop. Messages to the visitors are projected on the ground. For example, “Jump! Jump!" and "Almost at the end!” and "Thank you for playing with us!”. The position and direction of the displayed messages were tested in several patterns, and the best position for people to see the messages was decided in the end. (Image left and middle: under testing, Right: final version)

Controller Device

The main body was cut and assembled using a laser cutting machine from an MDF board. The buttons correspond to the 16 circles projected on the ground. Each button has a built-in LED to make the button light up. Full-color LEDs are built so that the color of the controller buttons matches the circle of the projected content. The buttons are made of 3D-printed parts, and when the buttons are pushed, two tact switches placed below each button are pressed. The two switches are connected in parallel, so it is recognized if either one is pressed. In addition, translucent filaments were used for the button’s material to diffuse the LED light.

Experience

• Experience using Open Frameworks, a new visual programming tool.

• Experience in connecting applications on a PC and a microcontroller via serial communication.

Future Work

I want to add sound effects and background music.

Gallery