General

Both product lines provide the same edge detection accuracy and material versatility. The difference is in how they integrate:

ODC 96 Family

• Best for: End users who want easy setup with touchscreen interface
• Requires SCU5 or SCU6x controller
• Intuitive touchscreen operation
• No coding required
• Sensing ranges: 48-960mm

1DC 960 Series

• Best for: OEMs and technical users who prefer Ethernet/PLC interfaces
• All-in-one sensor (no external controller needed)
• Direct Ethernet connectivity
• EtherNet/IP, PROFINET, EtherCAT, Modbus/TCP
• Sensing ranges: 96-960mm

Both are priced similarly—choose based on your integration preference, not cost.

Roll-2-Roll Technologies actuators are specifically designed for hydraulic cylinder replacement in unwind and rewind guiding applications:

What You Eliminate:

• Hydraulic fluid and the risk of product contamination from leaks
• Filter changes and fluid maintenance (typically 2-4 times per year)
• Seal replacement and valve rebalancing
• Hydraulic power unit (HPU) maintenance and energy costs

What You Gain:

• Clean, dry operation—critical for food, pharmaceutical, and medical applications
• Full thrust at zero speed (hydraulics struggle with static positioning)
• Smooth response at variable speeds without the "stick-slip" behavior of hydraulics
• Digital communication via EtherNet/IP, PROFINET, or EtherCAT for integration with modern PLCs

Retrofit Options:

• RLA Series: Rotary stepper with belt/pulley and ball screw, thrust up to 2,000 lbf
• BLA Series: Inline stepper with external ball screw for terminal guide applications

Most hydraulic retrofits can be completed in a scheduled maintenance window without major mechanical modifications to the existing stand structure.

No. With Roll-2-Roll® Sensors, you do not need to purchase or install a separate sensor for line/contrast guiding. The same ODC or 1DC sensor family handles edge detection, line guiding, center guiding, and contrast guiding. For most high-contrast applications, the standard infrared light source works for both edge and line detection. For low-contrast or UV-printed lines, white light or UV light source options are available.

Location and Function

• Terminal Guides: These are located at the very entry (unwind) and exit (rewind) of a roll-to-roll machine. Their purpose is to manage the master roll—either ensuring the web feeds correctly into the machine (unwind) or ensuring the roll winds up straight out of the machine (rewind).
• Intermediate Guides: These are located within the interior of the machine, typically just before a critical process such as printing, coating, laminating, or slitting. Their job is to shift the running web to align it for that specific downstream process.

Mechanism of Movement

• Terminal (Moving the Roll): Terminal guides function by moving the entire roll of material laterally. They typically utilize a "shifting stand" or "shifting base" on linear bearings to position the heavy unwind or rewind rolls.
• Intermediate (Moving the Web): Intermediate guides function by twisting or bending the web itself while the machine frame stays stationary. Mechanisms like Displacement Guides or Steering Guides displace the web by rotating or translating rollers over which the web passes.

Dynamics and Application

• Unwind vs. Rewind Dynamics:
  • Unwind Guides: Function as true guides. They shift the unwind stand to ensure the web enters the machine at a predetermined position.
  • Rewind Guides: Function as chasing systems. They do not control the web's lateral position; instead, the rewind stand moves to align the winding roll with the incoming web edge to ensure a straight roll.
• Intermediate Dynamics: Most intermediate guides (specifically Displacement and Steering guides) rely on the Normal Entry Rule, which states that a web will align itself perpendicular to the axis of the roller it is approaching.

Sensor Placement

• Terminal Guides:
  • Unwind: The sensor must be fixed to the machine frame (it does not move with the stand) and positioned immediately downstream of the shifting idler,.
  • Rewind: The sensor must be attached to the moving rewind stand so it moves with the carriage to "chase" the web.
• Intermediate Guides: The sensor is always located in the exit span (the span immediately following the guide roller) and moves with the web, not the guide mechanism. It should be placed as close to the exit roller as possible.

Actuator Requirements

• Terminal Guides: Because they often move heavy master rolls (potentially thousands of pounds), they typically require high-thrust actuators and robust mechanical rigidity to avoid resonance.
• Intermediate Guides: These move lighter guide frames and rollers, focusing more on dynamic response and low friction than raw thrust.

Preventing Loss of Focus

In line or contrast guiding, optical sensors or cameras are used to track a printed feature or line. These sensors require a stable focal distance to operate accurately. However, as the web guide mechanism actuates (moves back and forth), it creates a "twisting" effect in the web span, causing the web plane to shift closer to or further away from the sensor. This movement, known as pass line variation, can cause the sensor to lose focus, affecting the amount of light reflected back and disrupting the "teaching" or tracking of the feature.

Web Stabilization

The dead bar acts as a stabilizer. By wrapping the web over this bar, the web is forced to maintain a fixed distance relative to the sensor, regardless of the guide's movement or the twisting happening in the span. The sensor is then mounted specifically to "look" at the web directly over this dead bar.

Installation Specifications

• Mounting: The sensor should be installed to view the web while it is in contact with the dead bar.
• Wrap Angle: To prevent the dead bar from influencing the lateral dynamics of the web too heavily (which could cause drag or steering issues), the wrap angle should be kept small.
  • Dead Bar (Stationary): Maximum of 5 degrees wrap.
  • Idler/Backup Roller (Rotating): Up to 15 degrees wrap.

Application in Terminal Guides

For unwind or rewind applications where line guiding is required, the setup is slightly different to accommodate the moving stands:

• Unwind: A shifting idler or dead bar must move with the unwind stand to support the web, but the sensor must be fixed to the machine frame,.
• Rewind: The sensor moves with the rewind stand (chasing the web), and a fixed idler or dead bar is placed in the span just before the rewind.

Here are the primary advantages of center guiding:

Inherent Error Reduction (Averaging Effect)

The most distinct technical advantage of center guiding is that it averages the position of both web edges. By calculating the centerline based on inputs from two sensors (or one wide Roll-2-Roll® Sensor), the system inherently filters out edge imperfections.

• Fuzzy or Serrated Edges: If a web has rough, serrated edges (common in extrusion or nonwovens), a single-edge guide might oscillate as it tries to trace the jagged profile. Center guiding averages the left and right edge positions, smoothing out these variations and stabilizing the web.
• Wrinkles: Wrinkles effectively reduce the web width by pulling the edges inward. While a single-edge sensor might interpret a wrinkle as a position error and move the guide unnecessarily, center guiding sees the width change on both sides and maintains the centerline, reducing oscillation.
• Variable Opacity/Porosity: For materials that allow light to leak through (like nonwovens), legacy sensor readings can fluctuate. Center guiding significantly reduces the standard deviation of these errors compared to single-edge guiding. However, with Roll-2-Roll® Sensor this is not a problem.

Simplified Width Changeovers

In single-edge guiding, any change in web width requires the operator to physically move the sensor to the new edge location to maintain alignment. Center guiding eliminates this requirement for centered processes.

• No Sensor Repositioning: If the sensors are equidistant from the machine centerline and a wide sensor like Roll-2-Roll® Sensor is used, the web width can change (e.g., from a wide master roll to a narrower roll) without requiring the operator to move the sensors or adjust the guide point. The centerline remains constant relative to the machine. For legacy horseshoe/fork sensors it is important to ensure that width change does not snag the web. This is not an issue with Roll-2-Roll® Sensors since they are single sided. 
• Elimination of Mechanical Positioners: Traditional systems often required complex "sensor positioners" (motorized lead screws) to physically move sensors during width changes. Modern wide-sensor center guiding eliminates these moving parts, reducing mechanical wear and maintenance.

Simultaneous Process Monitoring

Because center guiding requires the detection of both web edges, it provides valuable secondary data that single-edge systems cannot:

• Width Measurement: The system can calculate and monitor the real-time width of the web while guiding it. This data can be used for quality control purposes.
• Web Break Detection: The presence of two sensors (or a wide field of view sensor) acts as a redundant web presence check. If the web breaks, the system knows immediately because it loses both edges, functioning as an inherent web break detector.

Process alignment

Center guiding is the standard requirement when downstream processes (such as printing, coating, or lamination) must be aligned to the middle of the machine rather than a specific edge. It ensures that despite variations in the incoming roll's width, the material remains centered relative to the tool or die or the print system.

Electronic guide point adjustment drastically simplifies product changeovers by eliminating the need for operators to physically reposition sensors when the web width changes. Instead of unlocking, moving, and re-locking a sensor hardware assembly, the operator simply changes the target position setting on the controller's touchscreen interface. Better yet with Roll-2-Roll® Controllers this can be completely automated with remote guidepoint adjustment either via industrial ethernet or digital I/O inputs.

Electronic guide point offers three specific benefits for product changeovers:

1. Elimination of Mechanical Adjustments & Safety Risks: In traditional "single edge guiding," a width change requires the sensor to be physically moved to the new edge location. This often forces operators to climb into the machine or reach into hazardous areas to adjust brackets. By using Roll-2-Roll® Sensor (e.g., 48mm to 960mm sensing window), the sensor remains fixed to the machine frame, and the "guide point" is moved electronically within the sensor's viewing window. This removes the operator from the machine, improving plant safety.
2. Reduction of Operator Error & Waste: Physical sensor repositioning is prone to human error. If an operator locks the sensor in the slightly wrong position, or if the sensor bracket is not rigid, the web will be aligned incorrectly, leading to immediate material waste. Electronic adjustment allows for precise, digital settings (e.g., 0.25mm increments with Roll-2-Roll® Controller) that are repeatable. Furthermore, these settings can be pre-programmed based on product codes, allowing for "recipe-based" changeovers where the guide point updates automatically without human intervention.
3. Removal of Mechanical Wear: Legacy systems sometimes use "sensor positioners" (electromechanical actuators that move the sensors) to automate this process. However, these introduce additional moving parts, maintenance requirements, and mechanical wear and tear. Electronic guide point adjustment achieves the same result mathematically using software and wide sensors, completely removing the need for mechanical sensor chasing mechanisms.

Unlike other forms of guiding, the goal is to align the rewind roll to the position of the incoming web, ensuring a straight wound roll.

Specific reasons for this configuration include:

• Chasing Control System: Rewind guiding is fundamentally a "chasing control system" rather than a lateral control system. The rewind stand must physically move to position the winding roll directly downstream of wherever the web happens to be.
• Maintaining Relative Position: If the sensor were fixed to the ground (as it is in unwind guiding), the system would not know the relative position between the winding roll and the incoming web. By attaching the sensor to the moving stand, the sensor moves with the carriage. When the sensor detects the web edge, the controller moves the entire stand (and the attached sensor) until the sensor is re-aligned with the web, effectively "chasing" it to maintain the correct relationship.
• Roll Alignment: This setup ensures that the edge of the rewind roll is constantly aligned with the edge of the approaching web, regardless of where the web is drifting laterally.

Ideally, this sensor should be located just ahead of the last fixed idler in the machine and as close to the winder as possible to minimize instability caused by the mechanical arm's stiffness.