Capability:Stepper Motors

Stepper Motors
Type	Actuation
Measures/Controls	Rotational position (open-loop step counting)
Common Hardware	NEMA 17, 28BYJ-48, A4988/DRV8825 driver boards
Enables Activities	Precise positioning, 3D printing motion, CNC control
Status	Stub - Not yet implemented in BRS robots

Stepper Motors is a actuation capability that rotates in precise angular steps without feedback sensors.

Overview

This is a stub page. This capability is not yet implemented in any BRS robot. This page exists to:

• Document the concept for future implementation
• Invite community members to add it to their robots
• Provide a starting point for hardware selection

What It Controls

Rotational position (open-loop step counting)

Common Hardware

NEMA 17, 28BYJ-48, A4988/DRV8825 driver boards

Enables Activities

Adding this capability to your robot would enable:

Technical Considerations

• **Advantages**: Precise step-based control, no feedback needed, holds position without power (some types)
• **Disadvantages**: Can skip steps under load, requires driver board, higher power consumption
• **Typical cost**: $5-20 per motor + $3-10 for driver
• **Interface**: Step/direction signals to driver board
• **Resolution**: 200-400 steps per revolution (1.8° or 0.9° per step), microstepping increases resolution
• **Torque**: High holding torque, varies by size

Contributing

Want to add this capability to your robot? Here's how:

1. Select appropriate hardware (see "Common Hardware" above)
2. Mount the hardware to your robot chassis
3. Wire to your microcontroller
4. Write driver code or use existing libraries
5. Test and calibrate
6. Document your implementation
7. Update this page with your findings
8. Share on Discord

See Also

• Capabilities - All capabilities
• Activities - What this capability enables
• Robotics Ontology - How capabilities fit into BRS knowledge structure