Renishaw: Artos™ DHR Rotary Absolute Magnetic Encoder System Readhead DHR162DC21BAAS15MW00
Artos is an absolute magnetic encoder system designed for motion control
applications as a feedback element for angle and velocity control loops.
A highly reliable measurement principle and processing provide low position
latency, high resolution and high angular velocity. The robust design protects the
readhead and magnetic ring from liquid ingress and high temperatures, so they
remain undamaged even in extremely contaminated and hot environments.
Artos provides a true-absolute position information immediately after power-on via the selected communication protocol. The
encoder system is extremely reliable due to the large installation tolerances (axial/radial/tangential offsets) and the robust IP67
design of the ring and readhead.
The measuring principle is based on a magnetic ring/scale magnetised with the incremental and absolute track with a pseudorandom binary sequence (PRBS) read by RLS proprietary sensor technology. Once installed, the encoder system does not need to
be calibrated. To ensure the installation is correct, the operator can observe the setup LED while rotating the magnetic ring/scale
in either direction.
The magnetic ring is available in two versions: exposed and protected with a cover foil. The version with the visible elasto-ferrite
layer, called the exposed ring, is intended for applications where aggressive liquids are not expected to damage the sensitive part
of the ring. The exposed ring can withstand dust, moisture and dirt. If, on the other hand, a thin layer of stainless steel is applied
over the elasto-ferrite layer, the ring becomes more robust and suitable for harsh environments. The cover foil can be applied in
two different ways. In one variant, the cover foil is wrapped around the circumference of the ring, with the elasto-ferrite layer of
the ring visible from the sides. This type of protection is suitable for high rotational speeds and protects the sensitive elasto-ferrite
layer from rotational forces. In the second variant, the cover foil is applied and welded around the entire circumference. This type
of protection gives the ring IP67 protection and can withstand significantly higher rotational speeds. The fully protected version
is intended for demanding applications, e.g. in the machine tool industry, where various aggressive liquids are present - oils,
coolants, greases, solid non-ferrous particles (swarf) and high-speed applications.
The magnetic rings are available in different sizes, from 57 mm up to 478 mm outer diameter. In addition, the readhead supports
partial arc applications from the smallest diameter of 200 mm upwards. For partial arc applications, the flexible magnetic scale
DS19 is used, which can be attached to shafts with larger diameters. The use of the DS19 magnetic scale does not support a full
360° rotation of the shaft, but is intended for applications with large shaft where full rotation is not required.