Evolutionary rather than revolutionary changes characterize the motion control market. Motors and motor controllers continue to gravitate toward higher performance and functionality as market demands become more stringent. At the same time, higher levels of intelligence — driven largely by software advancements, are giving engineers greater control and flexibility in designing motor-based systems.
The increasing complexity of motion control applications is driving many of the changes in motors and motor controllers. “Clearly, the applications we’re seeing are more complex, and more sophisticated— wireless communications, security, and networking,” said Kirk Barker, electronics product manager for Maxon Precision Motors Inc.
Peter Nachtwey, president of Delta Computer Systems, said, “One trend is the opening up of new markets for motion control technology being made possible by the advancing ease of use of motion controllers. Engineers that couldn’t justify the motion system development learning curve in the past are now able to make use of the technology. An example of this is the great increase in the number of motion controllers that are being used in engineering and production test environments.”
Though considered mature, the motion control market continues to show steady growth. Reported sales of motors, electronic drives, controllers, actuators and other motion control components are up 3.7% from the first quarter of 2007, according to a report by the Motion Control Association (MCA).
The report found that motors—brush and brushless, servomotors with gearings mounted, direct drive, linear motors and steppers, accounted for the largest percentage of motion control sales at 36.5%. “The findings show that the motion control market as a whole is expanding at a healthy rate and therefore represents an important area of vitality within the greater economy,” said Paul Kellett, MCA’s director of market analysis.
One area of progress has been in the electronic components used to create motors and motor controllers, according to Keith Kowalski, vice president of technology for Haydon Switch & Instrument Inc. “These components are smaller, more efficient, lighter, and more powerful,” said Kowalksi. “All this allows designers to use products in ways that were never thought to be possible before, even with the same motor or actuator.”
Component integration has also reduced the number of parts inside motors and controllers, saving space and giving designers more flexibility in designing motion control systems. “As components become smaller, manufacturers are able to integrate controllers and actuators into complete systems,” said Kowalski.
As motors scale up the performance curve, smaller motors are offering the performance of their larger counterparts. “Devices previously using 16-mm-diameter motors are demanding the same performance out of a 13-mm-diameter product,” said Ted Severn, director of sales and marketing for motor manufacturer MicroMo Electronics.
One motor trend is the increasing use of piezo motors for linear actuation. These motors, which replace traditional linear motors used with a ballscrew or leadscrew, provide precise positioning.
According to Scott Jordan, director of Nanopositioning Products for Physik Instrumente LP, piezo-based motors provide centimeters to travel — longer than the few hundred microns previously—and many kilograms of pushing and holding force. Piezo motors also provide sub-nanometer positioning resolution. They are finding use in applications from industrial automation to semiconductor test and metrology equipment, Jordan noted.