Managing cables and hoses may seem simple, but in reality it is an important part to of any well-functioning robot.

1. TECHTALK DESIGN
ADVICE SERIES
YOUR CONTACT
THE LESS IS MORE APPROACH TO
ROBOTIC CABLE MANAGEMENT
Cable management has come into
the limelight more and more
because machine reliability has Don Nester
increased dramatically in recent
Product manager, Chainflex®
years, even though robots have
continuous-flex cables
grown more complex.
DNester@igus.com
However, the methods used to
attach and guide cables have not
quite followed suit. Since the >> Subscribe to e-newsletter
1960s, cable management on
>> Contacts in your location
robots hasn’t changed significantly (on-site within 24-48 hours)
and, in fact, is often overlooked altogether. Managing cables and hoses
>> Request catalogs / free
may seem simple, but in reality it is an important part to of any well- samples
functioning robot.
>> myigus
Most experts agree one of the top blunders designers make is
underestimating cable-management issues. For instance, during a >> myCatalog
conference hosted by the Robotic Industries Association (RIA), a group
of leading system integrators cited cable issues as the number one
reason for downtime in robotics cells. Headaches range from tangled
and corkscrewed cables to complete breaks that cause downtime, lost igus Inc.
revenue, and damaged reputations.
PO Box 14349
East Providence, RI 02914
New Thinking P. 1-800-527-2747
Currently used systems try to keep the cables static, while everything F. (401) 438-7270
operating around them is dynamic. In essence, using one, long sales@igus.com
restrictive cable package prevents movement in sync with the robot.
Restrictions stress cables, which accelerates failure. Often, technicians
severely bind cables with excessive dress packs (protective coverings
www.igus.com

2. on cables and hose), cable ties, and even duct tape. The goal
might be to minimize tangling and interference with the
machine, but instead these techniques actually causes
corkscrewing and failure.
Instead, engineers need to consider a six-axis robot as three
separate segments: the sixth to third axis; the third to second
axis; and the second to first axis. This breakdown is imperative
to longer-lasting cables. Each cable segment should feature a
minimal dress pack, strain relief with service loops, and a
junction box that contains and protects the electrical
connectors joining the cables. For the best results, follow the
following recommendations.
From the sixth to third axis:
1. Use strain-relief cables (we’ll talk more about ‘long-life’ cables in an upcoming section) on the
moving end (sixth axis) with a one- to two-foot service loop.
2. Protect cables and hoses with a modular, multi-axis cable carrier.
3. Segment cables at the third axis and install a junction box for quick diagnostics and cable
replacement.
From the third to second axis:
1. Use strain-relief cables on the third axis with a one to two-foot service loop.
2. Use a modular, multi-axis cable carrier.
3. Segment cables and install a junction box at the second axis.
Finally, from second to first axis:
1. Strain-relief cables on the second axis with a one to two foot service loop.
2. Install a multi-axis, reverse-bend cable carrier to protect and guide cables and hoses rotating
around the robot.
3. Segment cables and install a junction box at the first axis.
Segmenting the dress pack into three shorter sections prevents it from wrapping, catching, or snagging
on machines, and minimizes stress on cables and hoses. This approach applies to any six-axis robot,
regardless of manufacturer or application. While other fixes, such as duct tape and ties wraps, might
work temporarily and cost less, in the long run properly designed dress packs reduce unnecessary
downtime and maintenance costs.
igus Inc. | 1-800-521-2747 | sales@igus.com | www.igus.com

3. Additional Tips
Another step that should extend cable life is to allow sufficient clearance inside the carrier for electrical
cables, pneumatic hoses and tubing for other media. This compensates for relative forces between
cables and hoses. Carrier suppliers typically provide this data.
For instance, general rules of thumb for igus®, Triflex® R carrier are:
1. Total cable and hose diameters must not exceed 60 percent of the carrier diameter.
2. Leave at least a 10 percent clearance between any two cables and hoses.
3. Cables and hoses need to move freely inside the carrier.
Safety is also a major concern within robotics cells. With the less-is-more approach, designers can let
cables and hoses move freely, but not to the point where they could potentially injure workers.
As six-axis robots evolve, cable-management systems need to develop along with them. Designers
should consider the less-is-more approach for every robotic applications, as it eliminates cable
damage, expensive maintenance and downtime. Of course, a number of other elements, including the
robot’s function, space constraints and budget also play a role. But for any combination, there is a
suitable less-is-more approach that keeps vital cables away from harm’s way while enabling them to
mimic the fluid movements of a six-axis robot.
Continuous-flex Cables
In addition to the appropriate dress pack, it is
imperative that six-axis robots use dynamic
cables specifically designed for continuous
flexing. Two important features to take into
account are a cable ’ s torsion-resistance and
shielding. Shielded cables face a greater risk of
failure, as constant movements can easily compromise the cable jacket. Use unshielded, high-flex
cables whenever possible to avoid problems.
For example, igus® offers its own range of robotic cables called CF Robot. These including hybrid, bus,
measuring system, fiber optic, motor, servo and more. All of these cables are specifically designed for
and tested in applications involving high levels of torsion and ideal for use in Triflex® R cable carriers.
In contrast to conventional braided copper shields, which are counter-wound, a torsion-resistant, tin-
plated copper shield sheath is used with CF Robot. The forces affected on the cable by any torsional
movement are largely absorbed by sliding and buffer elements between the sheath, shield and
insulation. This prevents early failure of the shield. The outer sheath material is a high-grade TPE
mixture with particularly good wear properties.
igus Inc. | 1-800-521-2747 | sales@igus.com | www.igus.com

4. Conclusion
If you’re working on a multi-axis robot application, consider taking a less-is-more approach to cable
management. It will extend the life of your cables and hoses and improve overall performance. If you
have any questions or want to discuss a specific application, please call 1-800-521-2747 to speak with
an igus® sales engineer.
Useful Links and Tools
Learn more about Triflex® R cable carriers.
Learn more about igus®' line of high-flex cables specifically for robotic applications.
Click here to read an archived edition of TechTalk about how to specify robot cables.
igus Inc. | 1-800-521-2747 | sales@igus.com | www.igus.com