A drive, at its most basic level, is a device that controls the speed of a motor. And there are as many drives as there are motor types and then some: drives for ac motors, dc motors and variable frequency drives among others.
Over the years, a lot of advances in motion control systems have happened at the drive level, due in large part to rapid developments in electronics. Those developments are continuing to change the landscape of motor drives. One such technological advance is the development of the drive-on-motor, or integrated drive servomotors. Allen Tubbs, product manager for Electric Drives and Controls at Bosch Rexroth, points to the company’s IndraDrive Mi drive system as an example, with a new addition of a machine-mount servo power supply. “This removes the need to mount a large power supply inside a machine control cabinet, and it fits with our development of cabinet-less control products, a growing trend in machine design,” said Tubbs.
“Another technological advance in drive technology is the capability to connect to the outside data system world, or the Internet of Things,” Tubbs added. As the “Big Data” industry continues to develop tools and technology to process machine floor data, the machine floor components must be capable of providing that data in an easy, usable form.
The packaging industry, said Tubbs, created a push for cabinet-free machine designs. Composite placement machines use motor-integrated drive technology to reduce wiring and minimize electric enclosures and exposure to composite and metal dust.
Last fall’s Pack Expo provided at least one real-world example, mentioned Tubbs. At the show, Cama displayed its IG 270 pick-and-place sorting machine with 12 four-axis delta robots. The machine had no control cabinet, and the necessary components that could not be mounted on the machine directly were built into the frame of the machine. The implementation of this technology leads to increased operation visibility for operators, increased accessibility for maintenance technicians and a smaller overall machine footprint for the end-user. These improvements provide a safer and more cost-effective machine, proving that with the correct technologies, it is possible to have a safer machine at a lower cost.
And on the user end of things, OEMs are expecting more intelligence and functionality in the drives, including (among other things) multi-Ethernet protocol support, cabinet-free drive design and single cable solutions.
Doug Burns, director of Business Development for Lenze America, also sees advances driven by user experience. “The biggest advances in automation and integrated control (drives and motion) is with ease of use,” he said.
Tom Kutcher, marketing communications manager for Yaskawa America, Drives & Motion Div., sees much the same thing. “Customers still desire ac drives that are even easier to use (meaning, they work out of the box without adjustments). Drive manufacturers are spending more of their time addressing these requests.”
Changes in the design of drives are also being spurred by changes in other industries. For instance, Burns adds that “the biggest growth area for motion control is with integrated robotics in machine design. Not only has the standard robot market grown, but robotic functions are now being integrated into packaging machines, assembly systems and material handling applications. This use can be attributed to easy-to-use kinematics programming tools, so that machine builders can easily configure the move profile, optimizing the move.”
Burns points out that the integration of robotics into machines has been one of tthe biggest changes over the last decade. “In the past, a customer would have used a fixed mechanical design,” he said. “Now they can leverage the flexibility of a robot for the motion that they need. Also, robot varieties have increased to allow the best match to what the application needs.”
Another driver is power quality. “Across many industries, including HVAC, oil and gas, and water, the concern for power quality continues to increase,” said Kutcher. “This is driving a movement for cost-effective, low-harmonic solutions, and some drive suppliers are responding with new impressive technologies.” Kutcher added that “market price pressures continue to keep ac drive companies looking for lower cost materials and more efficient ways to produce. Additionally, more attention is being paid to product designs that are more easily adaptable to variation in customer installation.”
For end users, these factors combined with manufacturing production increases means some good news: Prices have gone down while performance and features have increased.