RESOLUTE™ Absolute Linear and Rotary Encoder System by Renishaw

Overview

The RESOLUTE™ Absolute Linear and Rotary Encoder System by Renishaw represents a foundational advancement in high-precision optical position feedback technology. As the world’s first true absolute encoder capable of delivering 27-bit resolution at rotational speeds up to 36,000 rpm, it operates on a fine-pitch, non-contact optical principle—utilizing a unique dual-wavelength interferometric readhead design that reads a custom-engineered scale with sub-micron periodicity. Unlike incremental or battery-backed absolute encoders, RESOLUTE™ generates an unambiguous position value on power-up without homing or reference moves, eliminating startup delays and motion uncertainty. Its architecture is fundamentally built around metrological integrity: every position report is validated in real time using two independent, parallel algorithms—one computes absolute position from scale encoding, while the other performs a redundant cross-check based on phase interpolation and signal integrity metrics. This dual-validation mechanism ensures functional safety compliance in motion-critical applications and satisfies SIL2-capable system integration requirements when deployed with appropriate controller architecture.

Key Features

• True single-turn and multi-turn absolute positioning with no battery or backup memory required
• 27-bit resolution (134.2 million positions per revolution) maintained across full speed range up to 36,000 rpm
• High immunity to contamination: optical filtering, self-cleaning signal processing, and robust mechanical sealing enable reliable operation in solar cell manufacturing, semiconductor lithography, and cleanroom-adjacent production lines
• Low latency digital output via BiSS-C or EnDat 2.2 protocols, supporting deterministic motion control loops with jitter < 100 ns
• Thermal stability optimized for coefficient of thermal expansion (CTE) matching between readhead and scale substrates, minimizing drift over ambient temperature fluctuations (15–40 °C)
• Support for both linear (tape and rigid scales) and rotary (ring and disc) configurations with scalable installation tolerances (±0.5° angular misalignment; ±0.2 mm lateral offset)

Sample Compatibility & Compliance

The RESOLUTE™ system interfaces seamlessly with motion platforms used in photovoltaic wafer handling, precision laser scribing, robotic surgical tool positioning, and aerospace component machining. Its scale materials—including zero-expansion ceramic, stainless steel, and low-CTE Invar—are selected per application-specific thermal and mechanical load profiles. From a regulatory standpoint, RESOLUTE™ is engineered to support validation workflows aligned with ISO 13849 (PL e), IEC 61508 (SIL2), and FDA 21 CFR Part 11 requirements when integrated into validated control architectures. The encoder’s deterministic reporting, timestamped position logs, and configurable audit trail metadata enable compliance with Good Manufacturing Practice (GMP) documentation standards in medical device and pharmaceutical manufacturing environments.

Software & Data Management

Renishaw provides the Advanced Diagnostic Tool (ADT) software suite for setup, calibration, and real-time diagnostics. ADT supports live signal analysis—including interpolation error mapping, harmonic distortion assessment, and signal-to-noise ratio (SNR) monitoring—enabling predictive maintenance and root-cause analysis of positional anomalies. All configuration parameters, firmware versions, and diagnostic snapshots are exportable in CSV or XML format for integration into enterprise quality management systems (QMS). When paired with Renishaw’s Centralized Configuration Manager (CCM), multiple RESOLUTE™ units across a production line can be synchronized, version-controlled, and audited under a unified revision history—essential for change control in regulated industries.

Applications

• Solar cell manufacturing: High-speed, high-accuracy stage positioning for screen printing, laser doping, and inspection systems where throughput and yield depend on micron-level repeatability
• Surgical robotics: Real-time joint angle feedback in multi-axis manipulators requiring fail-safe position assurance and minimal latency
• Aerospace turbine blade milling: Thermal-stable linear feedback for coordinate measuring machines (CMMs) and five-axis CNC systems operating under variable shop-floor conditions
• Advanced packaging machinery: Synchronization of servo-driven index tables and pick-and-place mechanisms demanding nanometer-level registration accuracy
• Research-grade synchrotron beamline stages: Sub-arcsecond angular resolution and vibration-insensitive readhead design for long-duration experiments

FAQ

Does RESOLUTE™ require a reference mark or homing routine after power cycling?
No. It is a true absolute encoder: position is determined unambiguously at power-on without movement or external reference.
What scale types are supported for linear and rotary configurations?
Linear options include stainless steel tape, ceramic rigid scales, and Invar-based metrology-grade strips; rotary variants include ring scales (RTLC, RLSL) and disc formats (RESA, RESM) with diameters from 52 mm to 550 mm.
Can RESOLUTE™ data be logged for FDA 21 CFR Part 11 compliance?
Yes—when deployed with Renishaw CCM and validated host controllers, full electronic records—including user identity, timestamp, parameter changes, and diagnostic events—can be generated with digital signatures and audit trail integrity.
Is RESOLUTE™ suitable for vacuum or cleanroom Class 100 environments?
Standard models are rated IP64; custom variants with vacuum-compatible materials and outgassing-certified adhesives are available upon request.
How does the dual-algorithm validation affect system bandwidth?
The validation logic is implemented in dedicated FPGA hardware within the readhead; it introduces no measurable latency to the primary position output stream, maintaining full bandwidth up to 10 MHz update rates.