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Game-piece scorer / Six iterations

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Selected stages from the proof of concept to the final game-piece scorer, developed through six iterations.

The problem

The game piece needed to transfer from the intake to the scorer before being raised by the elevator and scored. With only about a dozen handoffs per match, each failed transfer cost us a valuable scoring opportunity. I worked through six versions of the scoring mechanism to refine that complicated handoff. I designed the mechanism for easy attachment and removal so I could swap versions and test changes quickly.

Before the iterations

How the handoff works.

The intake feeds the game piece into the scorer while the elevator is lowered. The scorer needs to maintain contact through the transition, then hold the game piece as the elevator raises it to scoring height.

Annotated photo labeling the intake, scorer, and elevator, with an arrow showing the game piece’s path from the intake into the scorer.
The path from intake to scorer

The finished handoff in action

  1. Step 01 / Testing the idea

    Proof of concept

    Does the initial idea work in theory? Since the scorer had to move with the elevator, I wanted to keep it as simple as possible, using just one motor. I tested the basic geometry to see whether the concept was worth developing and to establish a starting point for the first real prototype.

  2. First scoring mechanism mounted on the elevator, holding a PVC game piece.

    Version 2

    Version 2

    This version used two rollers on the bottom and worked as a proof of concept for scoring.

    The design
    Two bottom rollers supported the game piece for scoring.
    What testing revealed
    The handoff was still a problem. The game piece would ram into the top plate and stop instead of feeding into the scorer.

  3. Additional Version 4 handoff test

    Close-up of the game piece between the scorer roller shafts, showing the gap between contact points.
    Roller spacing during the handoff

    Version 4

    Maintaining contact through the handoff

    What I changed
    I moved the rollers so they could actively contact the game piece during the transition from the intake to the scorer.
    What testing revealed
    The rollers were too far apart. This left a dead zone where neither roller contacted the game piece, causing it to stop in the middle of the transition.
  4. Close-up of the scoring mechanism rollers and adjustable plate connecting the roller shafts.

    Version 5

    Testing the roller height

    What I changed
    I made a small plate that let me rotate the secondary roller to different heights so I could systematically test which position worked best during the handoff.
    What I learned
    Catching the top lip of the game piece to force it downward was crucial. But with two rollers, the angle needed for the handoff was not compatible with the scoring angle we found during the proof-of-concept stage. We needed a third roller.
  5. Side-by-side CAD views showing the elevator mount plate extended into the scoring window to act as a hard stop.

    Finished design in action

    Version 6 / Final version

    Final design

    With a third roller added, we reused the adjustable roller piece to find the best angle to tilt the game piece, then push it down into the scoring position.

    Problem
    The game piece carried momentum from the handoff and could fly straight through the scorer and out the other end. I tried using sensors to stop the rollers before it escaped, but that approach was unsuccessful.
    Solution
    I extended an existing elevator mount plate into the game piece’s path, creating a physical hard stop for it to run into instead of relying on the rollers stopping in time.

See the elevator this mechanism attaches to ↗