New applications for Hiperface DSL

New
motor feedback systems for new fields of application. SICK is expanding its
Hiperface DSL product portfolio, allowing demanding applications to benefit
from Hiperface DSL. The EES37 single-turn encoder and EEM37 multi-turn encoder are specifically designed for applications in
packaging technology, material handling, woodworking, and robotics. In these instances,
the encoders are distinguished by their
resistance to vibrations, extreme accelerations, or impact loads.

The new EES37 and EEM37 motor feedback systems are
available as single-turn and multi-turn versions with a 15- or 17-bit
resolution. The mechanical multi-turn can capture up to 4,096 revolutions.
Furthermore, mechanical engineers have the option of using the motor feedback
systems with or without the functional safety feature.

In terms of how they work,
and given their robustness against external
conditions, the new EES37 and EEM37 motor feedback systems do not use an
optical method when determining the angular position, but rather the capacitive
measurement principle. For this reason, the new series from SICK is also
resistant to dust and mechanical effects. The motor feedback system rotor
rotates in a capacitive measurement chamber and is
scanned in all its aspects. The EES/EEM37 series is therefore perfect
for tapping into new applications. With their highly dynamic reverse motions
and acceleration forces, robotic applications are a typical example.

In contrast to the commonly used resolvers, the new
motor feedback system provides robot manufacturers as well as machine and
systems manufacturers with all the advantages of the Hiperface DSL as a digital
protocol. These include, for example, the E2Prom with 8 kB of memory capacity, which allows motors to be recognised
automatically via the electronic type label – a true asset, particularly given the long and therefore expensive
engineering and commissioning times.

Easy
to install and precise

The new motor feedback system also benefits from the
easy installation. The feedback system can be
mounted to the flange and motor shaft without the need for additional
alignment tools. After the installation, the rotor position can be determined
precisely using a control command, meaning that reliable conclusions may be drawn as to the accuracy of the installation.
Motor manufacturers can, therefore, use this procedure to check outgoing goods,
for example. Furthermore, parameters (supply voltage, speed, temperature, and
the rotor position) are saved in cycles by the histogram function during
operation. If an error occurs, these values are also saved in the error log in
addition to the error message and will help you to analyse the causes of the
error.

Hiperface
DSL single-cable connection technology

With the Hiperface DSL protocol, SICK has triumphed as
the inventor of the single-cable interface in the machine and systems construction. The purely digital interface has
therefore revolutionised installation by halving the number of cables between
the drive and motor. This brings a number of advantages. Firstly, the connection
between the drive and servo motor no longer requires two cables, but one hybrid
cable, cutting the time needed for installation by half. Secondly, having fewer
cables also requires less space and applies less weight to the scales –
something which results in lower inertia
in highly dynamic applications.

Another general advantage of Hiperface DSL is the
performance of the new EES37 and EEM37 systems. The performance of a motor
feedback system is one of the crucial factors in determining how well the drive
system as a whole can be regulated. However, it is insufficient only to take a look at the resolution during
validation, as this only provides one value for the measurement scale
for feedback systems – and not a value for measurement accuracy. As a
consequence, resolution and measurement accuracy are always of equal importance
when selecting the most suitable system. Following this principle, SICK has
designed the new product family in such a way that makes it perfect for
applications in which robustness is just
as vital as measurement accuracy. This,
therefore, completes SICK’s portfolio of Hiperface DSL motor feedback systems.

Shock resistance goes hand in hand with safety
technology – something which is becoming increasingly important for modern
automated installations. That’s why the single-turn and multi-turn motor
feedback systems are complete with functional
safety. These system support functions are based
on safe speeds, as well as those based on safe single-turn positions. This ranges from safe stop functions and safe
speed limits right up to safe directions of movement or safely restricted
positions. Functions such as these are becoming more and more important,
particularly in material handling and robotics, for ensuring the safety of personnel
and machines without the need for cumbersome safety distances or elaborate
protective housings. The new motor feedback systems are expected to be
certified according to SIL2 as specified in IEC 61508 and to reach Performance
Level D as stipulated by ISO 13849 by early 2018.

A
tailored range of solutions

This complete product portfolio is a simple way for
SICK to create the opportunity to perfectly configure new motor feedback
systems with Hiperface DSL without any expensive excess functionalities.

SICK has the right encoder for every application. And
to prevent the broad range of solutions using Hiperface DSL as the shared means
of communication from growing uncontrollably, SICK has developed a universally
standardised mechanical interface for the motor feedback systems. Motor
manufacturers, therefore, have the chance to make adjustments to the feedback
system without considering the encoder option.

This feature is truly beneficial for motor
manufacturers as it allows them to produce components in a significantly more
standardised way. In practice, motor types can be
manufactured at high volumes, disassociated from any specific order,
because the specifications of the motor feedback system can be optimised to
customer requirements afterwards. This, therefore,
makes it possible to link large-scale series production to the
customer-specific application later down the line, since the motor manufacturer
does not need to make any changes to the end plate on the ventilation side or
to the shaft as the same mechanical encoder interface is used. Gone are the days of having to check which exact feedback
system will be used with a standard motor by the customer at a later point down
the line. As a result, the universal mechanical
interface to the encoder system considerably reduces variation also because
standardised replacement motors can be stored
in the warehouse, regardless of the specific motor feedback system required – a
true advantage for the manufacturer and operator in equal measure. To avoid
mix-ups between single or multi-turn when carrying out installations quickly
and in the heat of the moment, SICK also signposts these two types using clear
and unmistakable colour coding. At SICK, red stands for multi-turn and green
for single-turn.

Conclusion

With the new EES/EEM37 motor feedback systems, SICK
has expanded its portfolio for new applications. The new sensor design with its
capacitive measurement method makes the new product family resistant to dirt
and vibrations.

By Christian
Lohner, Product Manager for Motor Feedback Systems, SICK Stegmann GmbH,
Donaueschingen, (Germany)

Leave a Reply