Quick Look on Robot Cable Management
In robotic work cell designing, end-user has to consider multiple variables and components. Cabling is one of the important elements of robotics work cell which is mostly ignored in the design phase of the robotic work cells. Without proper planning for the robot cable management, cable wear may lead to the considerable downtime of the work cell.
The generic criteria considered while designing cables are.
Correct Cabling – Selecting the right type of cables for the required applications is very important for the robotic work cells. e.g welding and foundry work cells would require special demand in cables and using common flex cables will not be correct. Common mistakes done while selecting the cables are
- Selecting standard or off-the-shelf cables in place of high-flex cables.
- Not considering bend radius for the cables required for the applications. In accurate calculations of the bend radius causes cracks and results in failure of the conductor.
- Ignoring “how cables need to be protected?” – This depends on the application of the robots, application or usage and he environment.
- Installing the cables incorrectly while setting up the robotics work cell.
*Mark Noschang, applications engineering manager with Adept Inc. of Livermore, Calif., says, “A common mistake is not using the proper cabling for the job. Frequently, standard cabling is used where high-flex cable is required. The impact of repetitive motions on the cabling is magnified with faster robots, causing cabling used for end-of-arm tooling to wear prematurely.
Long Enough but Not too Long – Proper length is fundamental to the success of a robotic work cell.
*Uday Pathre, device building manager with DELMIA Corporation, Auburn Hills, Mich. “Integrators must make sure cables are long enough to be connected properly, but if too long, they could get snagged. End-users can save time and money by simulating the robotic system before it gets to the factory floor.”
Flexing vs. Twisting – Selecting the cables based on applicable subject to continuous flexing and that those are designed for torsion is important.
Firm but Not Rigid – Following points should be considered.
- Cables should not be secured too tight to the robotic work cells.
- Over-clamping of cables should be prevented in order keep the optimal movements of the cables.
Wire Less – Robotics work cell without cables would be the next big thing.
*Robert Winkel, senior product development engineer with FANUC Robotics America Inc. of Rochester Hills, Mich., addresses the desire for wireless work cells. “FANUC’s customers continuously inquire when wireless technologies will be used on robots. While we have seen an advance in some wireless communication equipment, these technologies still must be better validated in an industrial environment before they can be used to eliminate cables in robot systems.”
Besides there are many more parameters which are considered during the selection of the correct cables....
** In case of six-axis robots, cable design can be divided into three separate segments: the sixth to third axis; the third to second axis; and the second to first axis.
From the sixth to third axis:
- Use strain-relief cables on the moving end (sixth axis) with a one- to two-foot service loop.
- Protect cables and hoses with a modular, multi-axis cable carrier.
- Segment cables at the third axis and install a junction box for quick diagnostics and cable replacement.
From the third to second axis:
- Use strain-relief cables on the third axis with a one to two-foot service loop.
- Use a modular, multi-axis cable carrier.
- Segment cables and install a junction box at the second axis.
Finally, from second to first axis:
- Strain-relief cables on the second axis with a one to two foot service loop.
- Install a multi-axis, reverse-bend cable carrier to protect and guide cables and hoses rotating around the robot.
- 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.
In the next series of the blog post "DELMIA V5 Robot Cables Unplugged." we will go through DELMIA V5 Robot Cable Creation.. So keep watching for the post in this community...
References:
*Twisting and bending: A user's guide to robotic cables - Bennett Brumson, Robotic Industries Association
**The less is more approach to Robotic Cable Management – Techtalk Design Advice Series from IGUS [www.igus.com]
