Gyro Precision Glossary

Quick definitions for the core terms used in this session.

gyro: Short for gyroscope — a sensor inside the hub that detects how the robot is turning. It lets the robot feel which way it’s facing instead of just counting wheel-spins.

gyroscope: The full name for the gyro. It measures rotation, which the robot uses to make turns and straights more accurate.

IMU: Stands for inertial measurement unit — the chip inside the hub that holds the gyro (and more). When you read hub.imu.heading(), you’re asking the IMU which way the robot is facing.

heading: The direction the robot is facing, in degrees. It starts at 0 when the program begins, and positive = clockwise. You read it with hub.imu.heading().

use_gyro: The DriveBase command that turns the gyro on or off: robot.use_gyro(True). With it on, the same straight() and turn() commands use the gyro to hold a straighter, more accurate path.

accuracy: How close the robot gets to what you asked for. Turning the gyro on makes turns more accurate — they end up closer to the angle you typed.

drift: When the robot slowly veers off course because of tiny errors (slipping wheels, an uneven floor). Small drifts add up over many moves. The gyro reduces drift.

calibration: Measuring what the robot actually does and adjusting the numbers until the code matches reality. Today you calibrate a true 360° turn — your hub might need turn(357) or turn(362) for one real full turn.

DriveBase: The Pybricks tool that controls both drive motors together (from Day 1). It’s the thing you call use_gyro(), straight(), and turn() on.

degree: The unit turn() and heading() use for angles. A quarter turn is 90 degrees; a full spin is 360 degrees.

bug: When the robot does something you didn’t want. It’s not a mystery — it’s sensor data: the robot did exactly what the code said. Read the code to find what you actually told it to do.