Non-contact Power & Data Exchange For Assembly Automation

InductiveCouplersAssembly automation has evolved multi-fold since Ford’s first linear assembly plant. Assembly automation is of course commonly found in Automotive or heavy industries but it has found its way in small parts assembly, consumer goods and other industries that are embracing automation full on.

Typically, in assembly automation, pallets of sub-assemblies travel along the conveyor maze making stops at various stations to get further components and assemblies put on or some kind of operation is being performed on them.

Several times, inspection, measurement or other process specifics demand sensors and actuators to be on-board these pallets. A very common challenge people face in this environment is to provide power and communicate with this traveling assembly. Pin based automatic couplers and/ or manual intervention is common solution. As explained in my previous blog “Inductive Coupling for Robotic End Effectors” the pin based coupling has downfall of being susceptible to environmental elements and mechanical wear. Thus, offering a solution that requires some regular maintenance and related downtime. Manual intervention for inspection or measurement is of course time consuming and laborious activity.

Non-contact inductive coupling offers great benefits in this scenario. Typically, the base (transmitter) is mounted along the conveyor and the remote (receiver) is mounted on the moving pallets. As the pallet moves along the assembly line, the remote, when in-zone of the base, receives power and exchanges data over small air-gap with the base unit. There are three major benefits of this approach

  1. Because of magnetic induction phenomenon, these non-contact couplers are immune to dust, humidity, oil or vibrations, unlike the pin based couplers.
  2. Misalignment tolerance: Inductive couplers do not need to be in exact axial or angular alignment. They can tolerate angular or axial offsets. The amount of offset they can tolerate depends on the particulars but typically 10-20° angular offset is acceptable. So over-time when the conveyor system develops some slag, the inductive couplers won’t fail you that easily.
  3. Scalability: Inductive couplers come in various form factors and functionality that includes Power-only, input only, analog, configurable channels of inputs and outputs, and with IO-Link bi-directional communication. IO-Link inductive couplers offer the greatest benefits as they allow exchanging up to 32bytes of data bi-directionally- so in future if the I/O needs grow for your pallets, it can be easily handled.

You can always learn more about inductive couplers on Balluff’s website at www.balluff.us. You can also learn more in our Basics overview.

Inductive Coupling: Simple Concept for Complex Automation – Part 2

Image provided by Yaskawa America, Inc., Motoman Robotics Division
Image provided by Yaskawa America, Inc., Motoman Robotics Division

In the new era of flexible or customized manufacturing, where manufacturers are producing multiple products on the same production line or performing multiple operations in the same space, robotics is becoming cornerstone of automation. Industry innovators are applying a robot’s agility and multipurpose form to solving some real life challenges and stretching horizons of possibilities to all new levels. These next generation applications bring with them a new complex age of automation that was nearly unthinkable a decade ago.  When we think about flexible manufacturing what comes to mind first are the challenges of handling product changeovers. With robots that would mean changing out the end-effectors so the robot is ready quickly for next operation.

Figure 1: Tool changer example with pin couplers
Figure 1: Tool changer example with pin couplers

With the current trends in automation, demand for robotic tool changers (quick change for end-effectors) is growing at a fast pace. This is not only limited to automotive or heavy industries but also in packaging, bakery automation, food and pharma, and importantly in life sciences. End effectors are where these innovators primarily focus on to create value for their customers by handling products in most application suitable way.  The smarts of the end effectors, sensors and actuators, need power and the ability to communicate with the controller. Traditionally, this is achieved with pin-based coupling, where the robot approaches the tool changing station, engages the tool and very accurately mates the two ends of the pin couplers to power up the tool’s smarts.

The pin based coupling is effective and widely used today but it has few of its own issues: First, the pins of the tool when not in use are open and exposed to the environment- accumulation of dust, water or oil- causes nuisances in the connection process. Second, these are mechanical contacts and over time they wear out, bend, or break and cause un-intended downtime in the application.

Inductive coupling addresses all these issues and adds further value to automation. As explained in my previous blog. Both sides of the inductive coupler (Base and Remote) are fully encapsulated, typically with IP67 protection class, so that these couplers have no environmental issues to worry about. Since both sides are magnetically coupled, they are immune to vibrations. And, yes, since there is no-contact between the base and the remote side, there are no worries about bending or breaking of the pins.

Inductive coupling with IO-Link technology adds more benefits besides replacing the pin coupling. IO-Link enabled inductive couplers allow transferring up to 32 bytes of data in addition to power for actuation or sensors. When you connect IO-Link enabled I/O hubs or valve connectors to the remote side, (as shown in the picture below) you can also store identification data on the IO-Link hub or valve. When the connection is establish the controller can request the identification data from the tool to ensure that robot or system is utilizing the correct tool for the upcoming process. You might say, “wait a minute– this identification is also possible with pin-based coupling, so what is so great about inductive coupling?” Great question! With pin based coupling you first need to engage the tool to mate the two ends of the pin couplers and then request the identification. Up to 4-5 seconds are wasted before you realize it is a wrong tool. With inductive coupling, just the base need to be brought closer to the remote so that you could quickly couple and identify the tool before engaging the tool– saving you precious seconds. Coupling usually takes less than a second and most importantly the base and remote do not need to be well aligned to couple misalignment up to 15-20 degrees of angular offset or 2-4mm of axial offset still provides functionality.

Robot

So, you may ask, what are the limitations with Inductive coupling? The most important factor is how much energy your tool’s smarts require. Generally speaking 24W-48W is probably the most commonly available inductive couplers. If your tool requires any more than that then pin based coupling is the way to go. Another deciding factor is – metal dust in the environment. In the presence of metal dust on the surface of the couplers may cause interruptions in the communication as the basis of the communication is magnetic induction.

I hope this blog helps you decide the right coupler for your next application. In the next blog of this series we will review how inductive coupling can simplify automation along the assembly lines.

Rise of the Robots – 3 Ways to Be On Their Team

While originally a mixed reviewed 1994 console video game, the recently published report by The Boston Consulting Group titled “The Rise of Robotics”  really made me realize how important it is that we embrace robotics in our manufacturing processes.  And I strongly agree with this statement: “Because robots can sharply improve productivity and offset regional differences in labor costs and availability, they’ll likely have a major impact on the competitiveness of companies and countries alike.”  They studied the growth of the usage of robots in personal, commercial, military and industrial use and the numbers were quite powerful.  Of interest to me is the rise in industrial robotics; doubling in 5 years from $5.8b to $11.0b in 2015.  And the growth is expected to more than double again by 2025 to $24.4b in the industrial space.

What this means for manufacturers, machine builders and component suppliers is we need to make sure our people are trained to support this growth and that we we have strong peripheral technologies to support robots as they grow and expand.  Even today there are some great technologies available in sensors and controls that make robotic integration easier for manufacturing companies.

So here are the three ways to make sure you are your robot’s ally.

  1. Maximize Their Payload!

    No one wants to be treated like they can’t help… especially your robots, they want you to utilize them and feel appreciated.  For most robotics right now, payload size & payload weight is a limiting factor.  Mini sensing products with precision switch points, small form factors and low mass allow for the design of low weight, compact payloads without limiting the functionality or speed of the robot.

  2. Keep them Working!

    A working robot is a happy robot.  By adding flexible tooling or quick-change tooling to the end-effector of a robot you can have one arm perform multiple functions and keep idle arms to a minimum, increasing their value and “happiness.”  Multiple products are out there to allow for this, however there is a technology that allows for sensor connections through inductive coupling that dramatically decreases repair issues and downtime due to tool changer pins.

  3. Remove the Chains!  

    What’s the deal with cable dress packs… they look like really bad suspenders sometimes… you see them, you don’t like how they look, but you need it to keep your pants on… I guarantee that robots don’t like these things either… And with all that flexing something in there will fail regularly.  There are some great technologies to reduce the sensor cables running on the arm and add flexibility and they are supported by the open standard IO-Link (discussed in other posts here!).

So as you integrate robots more and more into the manufacturing we are doing, please start thinking how to align yourself as a robot’s ally.  Because I know I want to be on this guy’s team…

“Gorilla” Warfare in Metalforming – How to Couple Stamping Die Segments Without a Hard Wire Connection

This post will show how to couple stamping die segments without a hard wire connection, AND prevent the potential gorilla-like effects of forklifts during die change! Have you ever experienced or heard about a forklift removing a stamping die with the giant Mil-Spec connector still attached (OOPS!!!!)? It certainly isn’t a pretty sight. Below is a typical Mil-spec connector, they aren’t cheap or easy to re-wire.

Or, have you ever tried to figure out a way to add sensors in very complex progressive die segments that will facilitate rapid die change?  If so, I have an answer for you with a non-contact connector system. Take a peek at the picture below.

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