Day 8: Sphero BattleBots + Maze

As a group, decide what your maze looks like. You're going to lay it out on the floor with pipe insulation walls — soft foam half-tubes that your Sphero can bump without flipping over or knocking down. The pipe insulation is the wall your Sphero has to stay between.

Grab pieces of the pipe insulation and place them on the floor along the wall lines of your maze. Open side down, so they sit flat. The foam is soft enough that a Sphero can bump it without flipping, but firm enough to redirect the path.

This is teamwork — some students plan the layout, some carry pipe insulation, some position it. Talk to each other. Adjust as you go.

Before any Sphero rolls, walk the maze yourself. Start to finish. Are there parts that are too narrow? Turns that don't work? Fix anything that looks broken — once Spheros are running, you won't want to stop and reposition.

One driver at a time. Place your Sphero at START. Hit a timer on your phone when it starts moving. Stop the timer when it crosses FINISH.

If your Sphero bumps a wall, that's a wall hit — add 5 seconds to your time as a penalty.

Three runs per driver. Best time wins. Take notes on what worked: slow and steady? Full-speed and risky? Tight cornering or wide arcs?

If your Sphero keeps drifting in the wrong direction, you need to recalibrate. Tap the heading dial, spin it until the blue tail-light points at you, then try again. Most maze failures are calibration failures, not driving failures.

Before you tackle the maze, code a simpler shape: a square.

1. In the Sphero EDU app, go to Programs → Create New → Blocks.
2. Drag in a "Roll" block. Set it to speed 60, heading 0°, for 1 second.
3. Add another Roll block. Same speed, but heading 90°, 1 second.
4. Then 180°, then 270°, then back to 0°.
5. Hit play. Does your Sphero return to (roughly) where it started?

Now apply the same idea to the maze. Walk the maze yourself first — counting how long each straight section takes and what direction you turn.

Then write the program: one Roll block per leg of the maze. Roll → turn → Roll → turn → all the way to FINISH.

Tips:

• Test in chunks. Don't code the whole maze before running. Code 2–3 moves, run them, adjust, then add more.
• Time, not distance. Sphero rolls don't measure distance — they measure time at a speed. 1 second at speed 60 ≈ 1 foot on a smooth floor. Adjust as you go.
• Slower is more reliable. Speed 40–50 is easier to predict than 100.

Once your code gets your Sphero from START to FINISH without you touching the controls — you've done what NASA engineers do for Mars rovers. They can't drive them in real time; the signal delay is too long. Every move is pre-programmed. Same problem you just solved.

• 1 clear plastic cup
• 1 balloon (inflated to about the size of your fist)
• 1 wooden skewer (the popping tool)
• Masking tape
• Scissors

1. Place your Sphero inside the cup (cup is upside down — open end on the floor, Sphero sitting on the floor under the cup). The Sphero now drags the cup around when it moves.
2. Tape your balloon to the BACK of the cup. This is your target — and the only thing your opponents can hit.
3. Tape your skewer to the FRONT of the cup, pointing forward. This is your popping tool. Make sure the pointy end sticks out.

Before the arena opens, test your rig. Drive it around. Make sure:

• The cup actually moves when the Sphero rolls (sometimes the cup is too tight or too heavy).
• The skewer points where you're driving.
• The balloon stays attached.

Adjust before you face an opponent. You won't get time to repair mid-match.

• Stay inside the pipe insulation arena — same arena you used for soccer yesterday.
• Drive at opponents' balloons, not at their phones or hands.
• When your balloon pops, you're out. Pick up your rig and step back.
• No touching other people's Spheros or cups with your hands during a match.
• If a Sphero flips out of the cup, the driver can pick up and reset — but you've lost time.

Everyone in the arena at once. Last balloon standing wins the warmup round.

This is mostly chaos — and that's the point. You'll learn what your rig does well and what it doesn't. Pay attention: are you faster than you thought, or slower? Does your skewer actually reach? Is your balloon exposed from a direction you didn't expect?

Between warmup and bracket — 5 minutes to rebuild. Re-tape the balloon if it loosened. Reposition the skewer if it wasn't pointing right. Replace the balloon if yours popped. You learned something in the warmup. Use it.

Your instructor draws the bracket. Single elimination — lose a match, you're out. Win, you advance.

Each match: two drivers face off in the arena. Whoever pops the other balloon first wins. If both balloons survive after 90 seconds, it's sudden death — first hit wins.

Stay until the final. Even when you're out, watch — there's always a move you didn't think of.

• Autonomous systems engineer — programs self-driving cars, drones, factory robots. The "code the maze" challenge today is the entry-level version of what they do daily.
• Mars rover engineer (JPL) — NASA's Jet Propulsion Lab in Pasadena programs the Mars rovers. 40-minute signal delay means every move is pre-coded.
• Robotics competition engineer — BattleBots, RoboCup, FIRST Robotics. Real engineers design real combat robots for real prize money.
• Teleoperator (remote pilot) — drone pilots, surgical robot operators, undersea ROV pilots. Live control of robots in places humans can't safely go.
• Game / sim engineer — designs the physics and AI behind games like Mario Kart, Rocket League, and BattleBots video games. Riot Games and Blizzard in Irvine hire for this.

Local path: JPL is 45 minutes north. UCI's robotics lab is 10 minutes from PAL. Cal Poly Pomona, USC Viterbi, UCLA Engineering all have robotics programs. Cypress and Orange Coast CC have intro robotics that transfer cleanly.