Lecture Notes: Designing a 3D Moving Basketball Hoop

Overview

• Goal: To create a basketball hoop that can move in 3D to ensure every shot goes in.
• Purpose: Impress the speaker's wife by making a hoop that corrects for missed shots.

Development Stages

1. Initial Concepts

   • Started with a specially shaped hoop.
   • Progressed to a moving hoop.
   • Encountered limitations with backboard-based designs.

2. 3D Movement

   • Designed a robot to move in 3D space.
   • Challenges included tracking a basketball and predicting its path quickly.

Challenges and Solutions

• Time Constraint: Ball is in the air for a short time.
• Movement and Rotation: Required six degrees of freedom (six DOFs).
• Cable Actuated Robot: Chosen for its lightness and stiffness.
  • Cable and Motor System: Designed to adjust cable lengths to move the backboard.

Prototype and Mechanisms

• Actuator Design

  • Initial designs were complex; required wood and motors.
  • Used overpowered motors due to availability.
  • Integrated a disc brake system for safety.

• Motor and Power Management

  • Used a power distribution box due to high power needs.
  • Needed a microcontroller to coordinate motor movements.

Electronics and Programming

• Microcontroller: Small computer to control motor directions.
• Big Boss Program: Runs on a separate computer to predict ball trajectory and direct movements.
• Tracking System: OptiTrack camera system for precise ball tracking.

Calibration and Testing

• Inverse Kinematics: Calculate cable lengths based on target backboard position.
• Calibration Tools: Used a custom tool for accurate pulley positioning.

Ball Tracking Issues and Solutions

• Reflective Markers: Placed inside a foam ball for accurate tracking.
• Software Improvements: Required to handle tracking inaccuracies.

Final Testing and Adjustments

• Safety Concerns: Limited movement to avoid human injuries.
• Continuous Adjustments: Required to optimize the hoop's operation.

Conclusion

• Project Success: Achieved a functioning 3D hoop that impresses and entertains.
• Future Improvements: Potential for increased speed and more dynamic interactions.
• Community Support: Acknowledged support from viewers and sponsors.

Additional Information

• Sponsorship: Kiwico provided sponsorship, promoting educational crates for children.
• Future Plans: Intent to create larger and more complex projects.