SO-101 teaching arm
Compact serial arms are ideal for first closed-loop control: visible motion, bounded power, and a path from teach mode to simple teleoperation.
Animated schematic: three linked segments (pure CSS) to visualize joint motion — not a calibrated model.
Learning outcomes
- Name joint types and explain workspace vs singularities in plain language.
- Contrast joint-space jog with teach/playback for a classroom demo.
- List minimum safety checks before hands-on use.
Kinematic chain, serial bus basics, and modes: jog, teach, playback.
Small joint deltas in joint space; record two poses and interpolate.
Film a 20s clip: estop drill + one repeatable pick motion; post notes on the Forum.
Self-check
Why start in joint space?
What belongs in a session log?
STEM alignment: systems thinking, debugging physical systems, measurement & iteration — suitable for CSTA “creating” and NGSS engineering practices.
1. Kinematics & workspace
Understand the joint chain (base rotation, shoulder, elbow, wrist, gripper) and each joint’s software limits. Map the reachable workspace and discuss singular configurations where two joints align and small Cartesian moves require large joint motion.
2. Serial bus & power
Many teaching arms use a daisy-chained serial bus for servos. Stress clean cabling, correct termination, and separate logic vs actuator power so USB hosts do not brown out. Each actuator has an ID; first power-on calibration establishes zero without forcing the mechanism.
3. Modes: position, teach, playback
Start with joint-space jog commands, then teach mode (record key poses) and interpolated playback. Cartesian targets require inverse kinematics on the controller — confirm what the stock firmware exposes before promising Cartesian labs.
4. Teleoperation entry point
Map a gamepad or keyboard to small joint deltas; pair with Communication & architecture for latency and command-rate limits. For research-grade teleop stacks that also target OpenArm, see our demonstration data tutorial.
5. Compared to OpenArm
SO-101-class arms optimize for teaching throughput and portability; OpenArm targets higher bandwidth sensing, CAN-based drives, and learning-ready logging. Use SO-101 to build intuition, then graduate to OpenArm for data-centric workflows and same-day pickup at SVRC when you are ready for production-style hardware.