A Guide to Industrial Motion Control & Gearing Technologies

Which Servo System Fits Best—Sigma‑7 or the New Sigma‑X?

What Problem Does a Servo Solve?

A servo motor, paired with its amplifier (SERVOPACK), closes the position, speed, and torque loop in real time. When inertia changes or a load hits the axis, the amplifier corrects within microseconds. That stability translates to faster indices, tighter registration, and less scrap.

Sigma‑7 at a Glance

Sigma‑7’s notchless adaptive filtering lets you bolt the same motor onto three completely different mechanical loads and still meet a ±0.01 ° settling spec—with no manual gain tweaks. (yaskawa.com)

Sigma‑X: The Next Step for Data‑Centric Plants

Sigma‑X (sometimes written Σ‑X) starts at 3 W and runs up to 15 kW today, with 400 V dual‑axis models expected late 2025.

• 3.5 kHz loop bandwidth raises stiffness for delta robots and high‑G pick‑and‑place. (yaskawa.com)
• Built‑in condition monitoring—servo reports temperature rise, bearing vibration, and load skew to PLC/HMI.
• Advanced Safety Module (ASM‑X) supports 11 functions (STO, SS1, SLS, SLP, etc.) under SIL 3 / PLe without extra relays, simplifying wiring in ISO 13849 Category 4 builds. (yaskawa.com)

Rule of thumb: If your application needs data for OEE dashboards—or if you’re integrating with Industry 4.0 MES systems—choose Sigma‑X. For budget retrofits where inertias are known and change rarely, Sigma‑7 still nails the performance target.

Quick Selection Flow

1. Define peak/continuous torque → use Yaskawa sizing tool.
2. Check inertia ratio (< 20:1 preferred, < 10:1 ideal).
3. Pick feedback and network → EtherCAT dominates new OEM builds; pulse/analog keeps PLC‑5 vintage machines running.
4. Add gearing if torque or inertia ratio exceeds motor envelope (see Section 4).

iCube Control: Modular Automation Platform for Next‑Level Flexibility

Yaskawa’s iCube Control platform pairs tightly with Sigma‑X servos and GA‑series drives to create a single environment for motion, logic, safety, and secure connectivity.

When to choose iCube Control:

• You need to coordinate robotics, motion, and safety from one controller.
• Your machine requires high‑speed registration across 40 + axes or more.
• You plan to stream real‑time vibration and temperature data to predictive‑maintenance software.

Transition Path: From Legacy PLC + Servo to Sigma‑X + iCube

1. Pilot on one axis—swap analog servo with Sigma‑X EtherCAT unit.
2. Install iC9200 side‑car—control that axis while legacy PLC runs the rest.
3. Migrate remaining axes during scheduled downtime; reuse field wiring with EtherCAT junction boxes.
4. Enable FSoE last—validates I/O mapping and safe‑torque‑off before final sign‑off.

How Do You Size and Select a Yaskawa Variable‑Frequency Drive?

Selecting a VFD starts with load profile, duty cycle, and environment. The table below maps common needs to Yaskawa models.

Fast Sizing Checklist

1. Gather motor FLA and service factor (nameplate).
2. Add 15 % headroom for heavy start loads unless using vector mode with autotune.
3. Confirm enclosure rating (Type 1 panel, Type 12 floor, or 3R outdoor).
4. Check short‑circuit current rating—GA800 models carry 100 kA SCCR stock.

Why Drives Need Startup‑by‑Experts

Yaskawa extends GA‑series warranties by one extra year when a Certified Drive Specialist documents start‑up procedures. BlueBay’s field service team holds that certification, lowering your long‑term cost of ownership.

When Does a Machine Need High‑Precision Spiral‑Bevel Gearboxes?

A gearbox does three things: multiplies torque, shifts the mechanical axis (right‑angle or parallel), and improves inertia matching. Spiral‑bevel boxes add overlapping tooth contact, which raises torque density and quiets operation.

Key Specs of Tandler/DieQua Spiral‑Bevel Units

• Ratios 1:1 to 6:1; torque to 10 000 Nm; ≤ 4 arc‑min backlash. (diequa.com)
• Lubricated‑for‑life options cut maintenance in food and pharma settings.
• Hollow‑shaft through‑bores enable drop‑in servo coupling without keys or collars.

Do You Always Need a Gearbox on a Servo Axis?

No. Modern servos can often direct‑drive loads up to a 20:1 inertia mismatch. Use a gearbox when:

1. Peak torque > motor peak × 2.
2. Axis makes frequent positional moves < 150 ms.
3. You need a right‑angle interface to shrink the machine footprint.
4. Mechanical resonance appears above 300 Hz even after digital notch filters.

Tip: BlueBay loads gearbox data into Yaskawa’s SigmaWorks tool so autotune accounts for reflected inertia and compliance. That avoids the “stiff motor, soft gearbox” overshoot that plagues retrofit projects.

What Services Does BlueBay Automation Provide Beyond the Parts?

Proof Point

“I’ve been in business for over 33 years and have never experienced customer service like I did at BlueBay Automation… These guys absolutely blew my mind.”

— Darren Bach, President, Pacific Coast Marine Windshields