Complex motion controllers are scaring engineers away from productivity improvements in simple applications.
While visiting motion-control exhibits at trade shows, we see that vendors are leapfrogging one another with DSPs, multitasking controllers, high-speed networks, and graphical programming languages. These advanced units are certainly needed for some applications. However, companies are down sizing their engineering departments and relying more on their suppliers to provide complete solutions.
Thus, there is a divergence between growing motion-control sophistication and the technical capabilities of those persons the products are intended to serve. Plus, the capabilities continue to change at a blinding pace, while many of the needs have stayed the same.
One such example is my recent experience with upgrading my PC spreadsheet software. My old 1985 version does everything I need, and even has a number of still unexplored features. However, this reliable servant is no longer compatible with newer packages in the office. So I upgraded my old program — which resided in 700K on a floppy — with a new one that requires 7 megs on the hard drive. When using it, I am overwhelmed with multiple tool bars, submenues, spell checkers, shortcut icons, format options, and an 800-page reference manual. I am almost embarrassed to use such a powerful tool to manipulate a few columns of numbers. My spreadsheet need has not changed, but I now have to deal with more complexity to do the same job.
I believe this type of frustration also affects those considering motion control applications. The real needs have not changed, but many of the tools are now so powerful and flexible that it is easy to conclude that programmable motion control is only beneficial for large, high-visibility monumental projects involving many axes of synchronized servos and sophisticated operator interfaces. While monuments are impressive to look at, irrigation ditches are often more useful. One way to help revitalize our manufacturing infrastructure is to focus more on digging useful ditches and less on building monuments.
During visits to many OEMs and users involve in advanced automation, we walk by rows of manually operated machines enroute to the “monument” under assembly. When I ask about adding simple servos to these existing machines, I am told that they are old, that there is no one available to work on then, or that it would not produce a significant benefit.
In reality, some of the most successful projects are those that add a few sensors, controls, and actuators to existing, proven machines. Rather than requiring a great capital appropriation or a hardware- software design team, these small projects may involve a single axis and a simple move sequence. These tasks can frequently be defined and programmed by the people using or maintaining the machine. Doing a basic feed-to-length, ratio, or rotary cutoff application builds experience for determining the feasibility of using automation on a larger scale.
If we start by taking another look at simple applications where a few thousand dollars of equipment is applied in a few days and has a pay back of a few months, the knowledge and experience gained will serve us well as we go on to solve more complex problems.
— Donald G. White
MTS Systems Corp.
Eden Prairie, Minn.