TONiC™ incremental encoder system with RESM20 rotary (angle) ring
- Readhead size: 35 x 13.5 x 10 mm
- Resolutions to 1 nm
- Speed up to 3 673 rev/min
- Ultra-low Sub-Divisional Error (SDE): typically <±30 nm
- Vacuum compatible version available
- Optical IN-TRAC™ reference mark
- Low profile ring with large internal diameter for easy integration
- Super-compact encoder readhead with dynamic signal conditioning for improved motion control
- High dirt immunity
- Diagnostic kit to assist challenging installations and aid system optimisation
What is TONiC?
TONiC is Renishaw's super-compact, non-contact encoder system that offers speeds up to 10 m/s and, when combined with the Ti interface, resolutions down to 1 nm for both linear and rotary applications. TONiC systems are quick and simple to install with wide set-up tolerances and calibration at the push of a button. TONiC's dynamic signal processing gives improved signal stability with ultra-low Sub-Divisional Error of typically <±30 nm to help realise superior motion control performance.
What is RESM20 ring?
RESM20 is a one-piece stainless steel ring with 20 µm pitch graduations marked directly on the periphery, featuring the IN-TRAC™ optical reference mark. Two versions are available in a wide range of sizes (Ø52 mm to Ø550 mm). ‘A' section rings, which offer an impressive installed accuracy and feature a taper mount system which reduces the need for highly toleranced machined parts and eliminates eccentricity. ‘B' section thin rings, which are low inertia and mass, are also available. Both 'A' and 'B' section rings have a large internal diameter for flexible integration. The non-contact format eliminates backlash, shaft wind-up (torsion) and other mechanical hysteresis errors that are inherent in traditional enclosed encoders.
Why choose this encoder system ?
High tolerance to dirt, scratches and greasy fingerprints and speeds of 10m/s mean that TONiC is ideal for more challenging applications. Furthermore, the non-contact RESM operates without friction or wear ensuring excellent reliability.
Ultimate reliability and performance in a compact size
For ultimate reliability, consistent performance and high dirt immunity, TONiC readheads incorporate third-generation filtering optics tuned for even lower noise (jitter) and now further enhanced by dynamic signal processing including Auto Gain Control and Auto Offset Control. This combination – all incorporated inside the readhead - provides signals of unrivalled purity and ultra-low Sub-Divisional Error of typically <±30 nm. The result is smoother velocity control for improved scanning performance and increased positional stability; essential parameters for so many applications, all in a compact readhead.
Quicker and easier installation
A set-up LED on the readhead gives a visual indication of signal size and an optional diagnostic kit allows remote checking of the system performance when the readhead is concealed within the machine. Calibration of the reference mark and incremental signals is done at the push of a button with no mechanical adjustment or additional diagnostic tools. The IN-TRAC customer-selectable optical reference mark is embedded in the incremental scale for compact dimensions and simplified alignment. This yields a reference mark output that is bi-directionally repeatable to unit of resolution over the full operating temperature and speed range.
TD (dual resolution) interface
- Selectable dual-resolutions quadrature output.
- Ideal for applications that require high speed movement combined with finer precision motion.
DOP (dual output) interface
- Provides simultaneous digital quadrature and 1 Vpp signals.
- Designed for applications requiring one or more operations to be synchronised with a motion axis.
DSi (Dual Signal interface)
- Renishaw's DSi combines the incremental signals from two TONiC readheads on a RESM20 ring (REST20 ring for partial rotation applications) to compensate for the effect of bearing wander and eliminates odd error harmonics, including eccentricity to give total l installed accuracy of typically ±2.0 arc second.
Optional diagnostic kit
TONiC diagnostic software can be used to optimise the installation of TONiC encoders and provide a quick and comprehensive system calibration. The software must be used in conjunction with the TONiC diagnostic hardware which can be purchased from Renishaw using part number A-9411-0011. The hardware is connected to the PC via the USB cable (provided in the kit) or in-line with the customers' electronics.
Find out all about the TONiC diagnostic kit.
RESM20: one-piece low profile stainless steel ring. Standard ‘A' section with tapered internal diameter or low inertia ‘B' section rings available
Also available for partial rotation applications as REST20
Readhead size (LxHxW)
35 mm x 13.5 mm x 10 mm
|Coefficient of thermal expansion at 20 °C||15.5 ±0.5 μm/m/°C|
Ring outer diameter
52 mm to 550 mm. For larger custom sizes, contact Renishaw
8 192 to 86 400 (depending on ring size)
RESM20: single IN-TRAC reference mark ring
REST20: two reference mark ring for partial rotation applications
±3.97 to ±0.38 arc seconds (depending on ring diameter)
±4.20 to ±0.40 arc seconds (depending on ring diameter)
(See data sheet for details)
3 673 rpm at -3 dB (on 52 mm RESM20)
3 673 rpm (5 μm resolution TONiC on 52 mm RESM20)
Sub-Divisional Error (SDE)
Typically <±30 nm
Dynamic signal control
Real time signal conditioning including Auto Gain Control (AGC) and Auto Offset Control (AOC) for optimised performance during operation
(See data sheet for details of angular resolutions)
1 Vpp (20 μm period)
Resolutions from 5 μm to 1 nm
0.5 m, 1 m, 1.5 m, 3 m, 5 m and 10 m cable lengths with mini connector (connects direct to TONiC interface)
5 V ±10%, <100 mA (analogue system), <200 mA (digital systems) (unterminated)
100 m/s2 max @ 55 Hz to 2 000 Hz
1 000 m/s2, 6 ms, ½ sine
Operating temperature (system)
0 °C to +70 °C
* System accuracy is graduation error plus SDE. Graduation accuracy is the maximum difference between the angle measured by a single readhead and the true rotation of the encoder as graduated. Application disturbances such as eccentricity are not included.
Refer to data sheets for full details.
- Installation drawing: RESM angle encoder
- 3D model: TONiC™ readhead
- 3D model: Ti interface
- 3D model: TONiC™ interboard connector PCB
- 3D model: RESx 52 mm A section ring
- 3D model: RESx 57 mm A section ring
- 3D model: RESx 75 mm A section ring
- 3D model: RESx 100 mm A section ring
- 3D model: RESx 103 mm A section ring
- 3D model: RESx 104 mm A section ring
- 3D model: RESx 150 mm A section ring
- 3D model: RESx 200 mm A section ring
- 3D model: RESx 206 mm A section ring
- 3D model: RESx 209 mm A section ring
- 3D model: RESx 255 mm A section ring
- 3D model: RESx 300 mm A section ring
- 3D model: RESx 350 mm A section ring
- 3D model: RESx 413 mm A section ring
- 3D model: RESx 417 mm A section ring
- 3D model: RESx 489 mm A section ring
- 3D model: RESx 550 mm A section ring
- 3D model: RESx 52 mm B section ring
- 3D model: RESx 75 mm B section ring
- 3D model: RESx 100 mm B section ring
- 3D model: RESx 115 mm B section ring
- 3D model: RESx 150 mm B section ring
- 3D model: RESx 165 mm B section ring
- 3D model: RESx 200 mm B section ring
How it works
TONiC features the third generation of Renishaw's unique filtering optics that average the contributions from many scale periods and effectively filter out non-periodic features such as dirt. The nominally square-wave scale pattern is also filtered to leave a pure sinusoidal fringe field at the detector. Here, a multiple finger structure is employed, fine enough to produce photocurrents in the form of four symmetrically phased signals. These are combined to remove DC components and produce sine and cosine signal outputs with high spectral purity and low offset while maintaining bandwidth to beyond 500 kHz.
Fully integrated advanced dynamic signal conditioning, Auto Gain , Auto Balance and Auto Offset Controls combine to ensure ultra-low Sub- Divisional Error (SDE) of typically <±30 nm.
This evolution of filtering optics, combined with carefully-selected electronics, provide incremental signals with wide bandwidth achieving a maximum speed of 10 m/s with the lowest positional jitter (noise) of any encoder in its class. Interpolation is by CORDIC algorithm within the TONiC Ti interface, with fine resolution versions being further augmented by additional noise-reducing electronics to achieve jitter of just 0.5 nm RMS.
The IN-TRAC reference mark is fully-integrated in the incremental scale and is detected by a split photodetector within the readhead. As the diagram shows, the reference mark split detector is embedded directly into the centre of the incremental channel linear photodiode array ensuring greater immunity from yaw-dephasing. Yielding a reference mark output that is bi-directionally repeatable to unit of resolution at all speeds. This unique arrangement also benefits from an automatic calibration routine that electronically phases the reference mark and optimises the dynamic signal conditioning