No Sensors Needed!? A Magical Interactive Game Powered by Scratch and Human Power
I’m Ken Kuwako, your Science Trainer. Every day is an experiment!
Have you ever been to a high-tech arcade and played those “motion-sensing” games? You throw a ball at the screen, and the characters react instantly—it feels like pure magic. You might find yourself wondering, “What kind of incredibly complex sensors are they using?” But here’s a secret: you can recreate that same excitement yourself with nothing more than a clever idea.
Handmade with Scratch! The 20-Second Bug Hunt Challenge
I decided to build my own immersive motion game using “Scratch,” a programming language designed for education. You can check out the actual program right here.
The rules are simple: Hit the start button, and bugs begin swarming the screen. Your mission is to hit as many bugs as possible with a ball within a 20-second time limit. It’s a high-intensity score attack!
To play, you simply toss a real ball toward the screen like this:
The Secret Sensor? It’s a Human! The Analog Magic Behind High-Tech
Now, let’s pull back the curtain on this little trick. The moment the ball hits the bug on the screen, someone is secretly tapping that bug on the iPad. This triggers the program to make the bug vanish and log a point.
The player feels like a sophisticated sensor is tracking their ball, but behind the scenes, it’s a perfectly timed analog effort. In the world of science and design, this method—where a system appears automated but is actually operated by a human—is known as the “Wizard of Oz method,” named after the famous fairy tale.
You don’t need expensive infrared sensors to create an arcade-like experience. This “human-powered” approach is more than enough to spark joy. Here is how the player’s interaction flow is designed:
The user journey looks something like this:
Designing Experiences with Computational Thinking
You might ask, “Does this really count as programming?” The answer is a resounding yes! This is the essence of computational thinking.
The core of programming is building logic: “If [this happens], Then [do that].” In our game, as long as the logic “If the screen is tapped, then delete the bug and play a sound” is solid, the User Experience (UX)—the fun—remains the same. It doesn’t matter if the “trigger” is a cutting-edge laser or your friend’s finger sitting next to you.
For a deeper look at the programming logic, take a look at these diagrams:
You don’t need a massive budget to make the world more interesting; you just need a bit of creativity. Why not try building your own “Analog-Digital Hybrid” game to surprise your friends and family?
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