Summary

I developed an experiential balancing game. It is a labyrinth game in which participants control the tilt of the maze with a Nintendo Wii Balance Board and carry a ball to the goal without dropping it in any holes. As measured by the Wii Balance Board, the center of gravity of the experiencer's body is reflected in real-time in the maze's tilt. The game starts with the start button and ends when the ball falls into the hole. LEDs embedded in the maze guide the course with a flowing light production.

Purpose

• Create a work to be exhibited at a visiting day of a technical college to which I belonged for junior high school students.

• Communicate to junior high school students the knowledge and skills they will acquire upon entering a technical college.

Development Process

Sketch

In order for junior high school students to enjoy learning about the technical college and our department, the exhibits were designed to be interactive rather than to be observed. First, the theme was set as "an interactive labyrinth game," and a simple sketch of the image was created. The size of the maze was set to be approximately one meter square so that it would have a presence in the classroom at the venue.

Hardware Design

Hardware was designed in CAD. In addition to the maze itself, joint parts for tilting the maze, servo motor mounts, and sensor holders were also designed. The main body of the maze was made of wood, and the other parts were output by a 3D printer. This project was my first example of 3D printing applied to a work.

Maze body

Joint parts in the center of the maze

Servo motor mount

Assembly

The hardware was assembled after machining the materials and completing the 3D printing. I also worked concurrently to install the LEDs and sensors to be incorporated into the maze and design and build the electronic circuits and boards.

System Configuration

Two microcontroller boards (Arduino UNO) are used in this work. Both microcontrollers are connected with cables to communicate with serial communication. One unit (The green area in the system configuration diagram) controls the maze inclination using the user’s center of gravity position data. It communicates with the Wii Balance Board via Bluetooth. As input, it received the position data of the user’s center of gravity. As the output, control the angle of two servo motors that change the inclination of the maze. The other unit (The yellow area in the system configuration diagram) manages the scene transitions throughout the game. Two push switches, three photo sensors, and string LEDs are connected to the Arduino UNO. It controls the game's progress in response to inputs such as the start button, a switch that detects when the ball has dropped into a hole, and a sensor that detects when the ball has passed a checkpoint on the course. The Arduino in the yellow area can send a control signal that activates or deactivates the motion control of the maze to the Arduino in the green area.

Software Implementation

The system includes “standby,” “opening,” “activating,” and “ending” states. The maze does not move in the standby state, even if the player gets on the Wii Balance Board. Pressing the start button translates to an opening state and a countdown by LED starts. After that, the system translates to an activating state. During that, the maze tilts with the player’s center of gravity position. There are three checkpoints along the course, and LEDs flash when the ball passes through them. The game transitions to the ending state when the ball falls into the hole and hits the switch to detect the ball drop. During that, LEDs perform the lighting performance. This code is embedded in the Arduino in the yellow area in the system configuration diagram.

State transition diagram

Start button

Switch to detect ball drop

Two microcontrollers which manage the system

Exhibition Day

Many visitors experienced this work on the visiting day. Through this work, I could convey to many people the knowledge gained at a technical college and the joy of making things.

Experiences

• Creating parts using a 3D printer

• Consideration of part geometry for 3D printing

• Experience in production using Bluetooth communication devices

Gallery