Table of Contents

How a Linear Axis Works

A linear axis is more than a motor — it is a complete motion module: a drive, a guide, a carriage, an encoder, and a mounting. This page explains the anatomy of a NILAB linear axis and how it produces motion. Use it together with the How a Tubular Linear Motor Works page, which explains the motor itself.

The anatomy of a linear axis

Component Role Typical NILAB implementation
Drive Generates the force along the axis Tubular linear motor (GDM, MCSS), ironcore linear motor (LM, NL-BCJ), belt (ULCO)
Guide / rails Keeps the carriage on the axis and carries the load WON recirculating ball guides (LF seal), profile guides, T-slot profiles (ULCO)
Carriage / slide Moves the payload; supports the load Carriage with integrated guides and rails
Encoder Provides position feedback Magnet-type encoder (GDM), SIN/COS / ABZ / Hiperface / SSI (LM), absolute encoder (RM)
Mounting Connects the axis to the machine frame Base, flange, bellows, cable chain, T-slots

How the axis produces motion

- The drive generates force directly along the axis — there is no gearbox, lead screw, or belt between the motor and the load (except in belt-driven units like ULCO). This gives zero backlash and very high dynamic response. - The guide keeps the carriage on the axis and carries the load; it determines the stiffness and the natural frequency of the axis. - The encoder gives the position feedback that the servo drive or motion controller needs for closed-loop control.

Axis vs bare motor

A bare motor needs a guide, carriage, and encoder to become a usable axis. An integrated axis (GDM, LM, RM, MCSS, ULCO, NL-BCJ) is delivered ready to install — it already includes the guide, carriage, and encoder, and is matched to the motor.

Key performance factors

- Guide stiffness — determines the load capacity and the natural frequency of the axis; keep it high to avoid exciting vibrations (see Machine design: lowest natural frequency ≥ ~200 Hz). - Force — rated force (Fr) and peak force (Fp); for belt-driven units (ULCO) the belt also limits force and speed. - Precision — depends on the guide quality and the encoder resolution (SIN/COS with interpolation, absolute encoders). - Speed and acceleration — direct-drive tubular/ironcore axes are fast and dynamic; belt-driven units (ULCO) run quieter but have a lower speed and force limit.

* Linear axes selection * Multi-axis systems * How a tubular linear motor works * Machine design