Stage 1B - Power Transmissions
Learning Objectives
Students will: - Understand the relationship between torque and speed in power transmissions - Learn about motors, shafts, bearings commonly used in FRC - Gain proficiency modeling different types of power transmissions (gears, belts, chain) - Practice creating more complex assemblies and following best practices
Suggested Teaching Flow
1. Theory Introduction
- Begin with the basic physics of torque and speed, using real-world examples
- Explain mechanical advantage and gear ratios
- Introduce motors commonly used in FRC and their characteristics
- Discuss shafts, bearings and other supporting components
2. CAD Skills Introduction
- Demonstrate use of relevant Featurescripts (Belt & Chain Gen, Shaft Generator)
- Show how to calculate center-to-center distances and gear ratios
- Introduce MKCAD library components for power transmission
- Explain best practices for modeling power transmissions
3. Guided Practice
Have students complete 3 progressively more complex exercises:
Exercise 1: Simple Gearbox - Single stage reduction - Focus on basic gearbox plate design - Introduction to MKCAD and standard content
Exercise 2: Two Stage Gearbox
- Multiple reduction stages
- More complex plate design
- Part lightening techniques
Exercise 3: Belt and Gear Transmission - Mixed power transmission types - Frame integration - Advanced layout sketching
4. Assessment & Support
- Review student work as they complete exercises
- Common issues to watch for:
- Improper gear/belt spacing
- Over-constrained shafts
- Poor organization of features/assemblies
- Missing considerations for manufacturing
- Provide feedback on best practices and design intent
Tips for Success
- Emphasize importance of layout sketches in power transmission design
- Encourage use of design calculators and references
- Have students explain their design choices
- Point out real examples of power transmissions from FRC robots
- Share common pitfalls and solutions
- Make connections to future mechanism designs
The goal is to build strong fundamentals that will enable students to design more complex mechanisms in later stages. Focus on good practices and understanding rather than speed for now.