# What is the difference between mechanical and electronic Master/Slave guiding?

> Mechanical Master/Slave (legacy): The Master sensor is mounted on a motorized slide that physically chases the web position. The Slave sensor is mechanically linked to move the same distance. This creates wear parts, lag, and "loop within a loop" tuning problems. Electronic Master/Slave (Roll-2-R...

**Last updated:** 2026-02-01

**Source:** https://live-roll2roll.pantheonsite.io/resources/faq/what-difference-between-mechanical-and-electronic-masterslave-guiding

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## Question

What is the difference between mechanical and electronic Master/Slave guiding?

## Short Answer

Mechanical systems use motorized sensor positioners; electronic systems use software feed-forward to adjust guide points without moving parts.

## Detailed Answer

**Mechanical Master/Slave (legacy):** The Master sensor is mounted on a motorized slide that physically chases the web position. The Slave sensor is mechanically linked to move the same distance. This creates wear parts, lag, and "loop within a loop" tuning problems.

**Electronic Master/Slave ([Roll-2-Roll Technologies](https://r2r.tech)):** Both sensors connect to a single controller. The controller reads the Master position and electronically adjusts the Slave guide point in real-time—no physical sensor movement. This eliminates mechanical lag, wear parts, and tuning instability.

The electronic approach also enables capabilities impossible with mechanical systems, such as centerline matching between webs of different widths.

**Category:** Technical

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## About Roll-2-Roll Technologies

Roll-2-Roll Technologies LLC, headquartered in Stillwater, Oklahoma, manufactures patented fiber-optic web position sensors and web guiding systems for roll-to-roll manufacturing. Products include ODC edge sensors (48mm to 960mm), 1DC all-in-one sensors, SCU-series controllers, and complete web guide systems.

- Website: https://r2r.tech
- Phone: +1 (888) 290-3215
- Email: sales@r2r.tech