Multi-Axis Motion Control & Servo Systems Knowledge Hub

Motion control is the engineering discipline of orchestrating motor velocity, acceleration, and position trajectories in hard real-time to execute synchronized machine processes.

Omron NJ and NX series controllers incorporate dedicated hardware trajectory engines coupled directly to EtherCAT, communicating natively with 1S and G5 series servo drives via standardized PLCopen motion commands.

Omron Servo Drive Families

Drive Series	Drive Model	Power Range	Feedback (Encoder)	Fieldbus	Distinguishing Features
Omron 1S	`R88D-1SN`	100 W – 15 kW	23-bit Multi-Turn Absolute (Battery-free)	EtherCAT	Battery-less absolute encoder, integrated STO / FSoE safety, screwless push-in terminals
Omron G5	`R88D-1KN`	50 W – 15 kW	17-bit / 20-bit Incremental & Absolute	EtherCAT / Pulse	Proven industrial durability, broad servomotor line-up, external battery backup
Accurax G5	`R88D-KN`	100 W – 5 kW	Linear Optical / Magnetic Scale	EtherCAT	Direct linear motor drive, ironless core high-dynamic stages

PLCopen Motion Function Block Architecture

In Sysmac Studio, motion sequences are programmed using standardized PLCopen function blocks (FBs):

1. Single-Axis Motion Blocks

MC_Power: Energizes the servo axis and enables torque generation (Servo ON / OFF).
MC_Home: Executes axis origin referencing (Limit switch, proximity marker, encoder Z phase, or push-to-stop torque limit).
MC_MoveAbsolute: Moves the axis to a target coordinate with specified velocity, acceleration, deceleration, and jerk.
MC_MoveRelative: Advances the axis by a relative distance offset from its current position.
MC_MoveVelocity: Drives continuous speed regulation independent of position targets.
MC_Stop & MC_Halt: Decelerates the axis to a controlled stop.

2. Multi-Axis Synchronization Blocks

MC_GearIn / MC_GearOut: Synchronizes two axes via an adjustable electronic gear ratio (Numerator / Denominator).
MC_CamIn / MC_CamOut: Couples a slave axis dynamically to a master axis trajectory defined in a multi-point Cam Table (flying shears, rotary cutters).
MC_Phasing: Introduces dynamic phase shift offsets between synchronized axes on the fly.

Field Commissioning Lessons & Tuning

Critical engineering checks during servo commissioning:

Mechanical Axis Scaling (Unit Conversion): Define precise physical units (e.g., millimeters per motor revolution on a ball screw) under Sysmac Studio Axis Settings. Any discrepancy propagates through all target coordinates.
Following Error Limits: Configures the allowable deviation threshold between command position and actual encoder feedback. Setting this window too narrow triggers nuisance trips during high acceleration; setting it too wide masks mechanical binding.
Resonance Suppression & Notch Filters: Use Sysmac Studio Autotuning to calculate load inertia ratios and engage adaptive notch filters to eliminate high-frequency mechanical resonance spikes.

Motion Control Tutorials & Field Guides

Introduction to Omron NJ/NX PLC Programming: Motion axis configuration and Structured Text status polling.
1S and G5 Servo EtherCAT Homing Modes (Upcoming): MC_Home parameterization, mechanical stoppers, Z-phase alignment, and error recovery.
Master-Slave Synchronization: MC_GearIn & MC_CamIn (Upcoming): Electronic gearing and Cam Table Editor profiling workflows.
Thermoforming Multi-Axis Servo Case Study (Upcoming): High-speed station synchronization and cycle-time optimization.

Official Documentation Reference

Omron W507: NJ/NX-series Motion Control Instructions Reference Manual
Omron W508: NJ/NX-series Motion Control User’s Manual
Omron I580: 1S-series with Built-in EtherCAT Communications User’s Manual
Omron I571: G5-series with Built-in EtherCAT Communications User’s Manual