One of the major topics among motion control professionals is the number of applications that are stand-alone, single axis systems with little or no external interaction between other motion systems. There is great debate about how much of the overall market is single axis and how much is multi-axis. The industry has always engineered high performance multi-axis controls with 32 or 64 axes capability, with 20 mHz feedback rates to handle linear motors, and computing capability to coordinate as many axes as needed.
With single axis applications, the computing requirements are pretty low and performance requirements are generally simple. If the application uses a PLC as the main control system, its easy to make the motion control a sub-system that is only connected to the main control by inputs and outputs. There are lots of “indexing controls” that will provide good motion performance with a variety of motor technologies.
Many folks I know estimate that the motion market is 80-90% “low performance” single axis systems. So why all the focus on the complex, high end control platforms. In motion control, as with many technology driven markets, the reputation of the brand is built on high performance solutions.
However, this poses a significant problem. How does the industry create products that satisfy the requirements and still create significant differentiation to sell their solutions. Motion control suppliers, being the clever types that they are, have proliferated all sorts of solutions over the last few years. One solution from Animatics combines the motor, drive electronics, controller and communications capabililty all in one package. This eliminates interconnect cabling between the drive electronics and the motor, which in many servo systems costs between 10 and 20% of the hardware cost.
There are a number of stepping motor companies that supply an integrated stepping motor and control. Check out the wide variety of products offered by IMS, AMCI, Lin Engineering and others. The integrated drive and motor are very space efficient and simple to interface with.
All of these products reflect great creativity and value. But its still difficult to differentiate among the many products.
Sometimes, as you get into the details, there may be specific features that will determine the suitability of one product over another. But for me, it is symptomatic of an emerging problem that proliferates all over the motion control and automation industry. There are many overlapping products on the market. For example, every major supplier of multi-axis controllers has a PC based control platform and flat screen interface. So do the PLC companies.
The cost per axis for a motor and drive has fallen steadily. Power mosfet costs, a significant cost component in most drives, have fallen by half in the last few years. The next generation of embedded processors for high performance motor control are half the cost of DSPs. Yes, magnet prices have been rising, copper is up, lamination steel is up. But overall, prices for motion control components are falling.
When there are a number of comparable control platforms available, there can only be differentiation based on some new technology that makes the product clearly superior to other offerings, or based on cost reduction. With increasing competition within the industry and competitive product offerings from foreign sources, the most likely scenario for the coming few years is declining prices.