Overview

Shooting Game is an interactive game controlled using a Leap Motion sensor.

Players move their hands to control the player character and close their hands to fire projectiles at targets falling from the top of the screen. When a projectile hits a target, a visual effect is displayed.

Objective

The objective of this project was to gain experience developing a system in which projected visuals and physical hardware, specifically LEDs, operate in synchronization.

Development Process

Concept Sketch

I first created a simple sketch of the proposed system.

An LED-integrated screen was positioned on a table with a Leap Motion sensor placed in front of it. A projector was installed above the screen to display the game visuals.

Development Approach

To synchronize the projected visuals with the LEDs, I connected a custom LED controller board to the PC.

The PC sent LED commands to the microcontroller through serial communication, allowing the physical lighting effects to respond to events occurring within the game.

After we agreed on the overall system concept and divided the responsibilities, the game software was developed by my collaborator.

Today, this type of system architecture feels relatively straightforward to me. At the time, however, I had little experience integrating projected visuals with physical devices, so determining how to synchronize the video and LEDs required considerable research and experimentation.

Hardware

I constructed an LED-integrated screen and a mirror attachment that redirected the projector image onto the screen.

The screen was built as a 10-mm-thick cardboard enclosure with LEDs installed inside. To balance light diffusion, transparency, and structural strength, the upper surface was made from a combination of translucent acrylic and white paper.

The projector attachment was fabricated using a 3D printer. It was designed to hold a commercially available mirror and could be mounted directly onto the projector.

Redirecting the projection toward the floor caused some trapezoidal distortion, which was compensated for using the projector’s keystone correction function.

LED Controller Board

I designed a dedicated controller board equipped with the following components:

• Microcontroller

• Step-down voltage regulator

• DIP switches for mode selection

• Serial communication module

Because the project used serially addressable LEDs, only a small number of microcontroller pins were required.

An ATmega328 microcontroller was used, although in retrospect, its processing capability and number of available I/O pins exceeded the actual requirements of the system.

Game Design

The game was controlled through hand tracking using the Leap Motion sensor.

The player character moved horizontally according to the position of the participant’s hand. Closing the hand triggered the firing action.

When a projectile collided with a target, the target disappeared and a visual effect was displayed.

The LEDs represented the game elements using different colors:

• Green: Player character

• Yellow: Projectile

• Red: Target

The operating instructions shown in the image were created by my collaborator.

Exhibition

The project was exhibited at our college festival, where it was experienced by many visitors.

Key Learnings

• Experience synchronizing projected visuals and physical hardware through serial communication

• Experience using a stereolithography 3D printer