October 13, 2015 Volume 11 Issue 38

Motion Control News & Products

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Telescoping linear actuators for space-constrained applications

Rollon's new TLS telescoping linear actuators enable long stroke lengths with minimal closed lengths, which is especially good for applications with minimal vertical clearance. These actuators integrate seamlessly into multi-axis systems and are available in two- or three-stage versions. Equipped with a built-in automated lubrication system, the TLS Series features a synchronized drive system, requiring only a single motor to achieve motion. Four sizes (100, 230, 280, and 360) with up to 3,000-mm stroke length.
Learn more.


Competitively priced long-stroke parallel gripper

The DHPL from Festo is a new generation of pneumatic long-stroke grippers that offers a host of advantages for high-load and high-torque applications. It is interchangeable with competitive long-stroke grippers and provides the added benefits of lighter weight, higher precision, and no maintenance. It is ideal for gripping larger items, including stacking boxes, gripping shaped parts, and keeping bags open. It has high repetition accuracy due to three rugged guide rods and a rack-and-pinion design.
Learn more.


Extend your range of motion: Controllers for mini motors

FAULHABER has added another extremely compact Motion Controller without housing to its product range. The new MC3603 controller is ideal for integration in equipment manufacturing and medical tech applications. With 36 V and 3 A (peak current 9 A), it covers the power range up to 100 W and is suitable for DC motors with encoder, brushless drives, or linear motors.
Learn more.


When is a frameless brushless DC motor the right choice?

Frameless BLDC motors fit easily into small, compact machines that require high precision, high torque, and high efficiency, such as robotic applications where a mix of low weight and inertia is critical. Learn from the experts at SDP/SI how these motors can replace heavier, less efficient hydraulic components by decreasing operating and maintenance costs. These motors are also more environmentally friendly than others.
View the video.


Tiny and smart: Step motor with closed-loop control

Nanotec's new PD1-C step motor features an integrated controller and absolute encoder with closed-loop control. With a flange size of merely 28 mm (NEMA 11), this compact motor reaches a max holding torque of 18 Ncm and a peak current of 3 A. Three motor versions are available: IP20 protection, IP65 protection, and a motor with open housing that can be modified with custom connectors. Ideal for applications with space constraints, effectively reducing both wiring complexity and installation costs.
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Closed loop steppers drive new motion control applications

According to the motion experts at Performance Motion Devices, when it comes to step motors, the drive technique called closed loop stepper is making everything old new again and driving a burst of interest in the use of two-phase step motors. It's "winning back machine designers who may have relegated step motors to the category of low cost but low performance."
Read this informative Performance Motion Devices article.


Intelligent compact drives with extended fieldbus options

The intelligent PD6 compact drives from Nanotec are now available with Profinet and EtherNet/IP. They combine motor, controller, and encoder in a space-saving package. With its 80-mm flange and a rated power of 942 W, the PD6-EB is the most powerful brushless DC motor of this product family. The stepper motor version has an 86-mm flange (NEMA 34) and a holding torque up to 10 Nm. Features include acceleration feed forward and jerk-limited ramps. Reduced installation time and wiring make the PD6 series a highly profitable choice for machine tools, packaging machines, or conveyor belts.
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FAULHABER IEP3 incremental encoder: Impressive accuracy through latest chip tech

With a diameter of just 8 mm, FAULHABER's new IEP3 incremental encoder is lightweight and compact yet still offers a resolution up to 10,000 lines per revolution -- made possible by the latest chip technology with high interpolation. The chip ensures a high positional accuracy of 0.3° m as well as high repeatability thanks to accuracy compensation. Application areas include telescopes, microscopes, lasers, and cameras; semiconductor production; robotics; and prosthetics.
Learn more.


Compact wheel drive for automated guided vehicles

Nanotec has introduced the WD42 compact wheel drive, a very short drive unit for automated guided vehicles (AGVs) and service robots. Each unit consists of a powerful BLDC motor, a high-torque planetary gearbox, a magnetic encoder, and an exchangeable wheel. All components are integrated directly at the wheel, which makes the drive only 103 mm long and reduces the number of moving parts and connections.
Learn more.


Bottom tapped rails available for quick ship

Bottom tapped rails are useful for mounting from the bottom of a base, as well as when contamination protection is required -- eliminating the need for bolt-hole caps. See the available models from THK, including standard and radial LM guides and standard and radial caged ball. All units are available for quick shipping.
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Hybrid actuation system reduces energy consumption, simplifies designs

Learn how a leading manufacturer of household cleaning products solved its downtime problems due to an overloaded ball screw in its production-line electromechanical automated plastic cap dumping function. A Hybrid Actuation System (HAS) did the trick, combining the controllability of traditional electromechanical actuators with the power density, longer life, and failsafe conditions commonly found on traditional hydraulic systems.
Read this informative Parker blog.


Machine tending solution now compatible with any CNC machine

The Robotiq Machine Tending Solution has made automation accessible to businesses of all sizes, overturning the belief that automation is too complicated. The company says their part-feeding solutions can provide up to a 30% production runtime increase -- without communication cards, expensive wiring, custom programming, or permanent modifications.
Learn how to boost your CNC productivity.


How to implement redundancy in stepper motors

Some of the recent research activities in the area of electric motor drives for safety-critical applications (such as aerospace and nuclear power plants) are focused on looking at various fault-tolerant motor and drive topologies. After discussing different solutions, this article focuses on a miniature permanent magnet (PM) stepper motor design that provides increased redundancy.
Read this informative Faulhaber article.


Why choose electric for linear actuators? When precision, multiple positions, repeatability, or position feedback is important

Tolomatic has been delivering a new type of linear motion technology that is giving hydraulics a run for its money. Learn the benefits of electric linear motion systems, the iceberg principle showing total cost of ownership, critical parameters of sizing, and conversion tips.
Read this informative e-book. (No registration required)


New mini gearhead for robotics, semiconductor fab

Harmonic Drive is proud to announce the release of its CSF-2XH mini gearhead designed for servo and stepper motors. Available with an output shaft or flange, these gearheads are offered in four sizes with gear ratios of 30:1 to 100:1 and peak torque of .5 to 28 Nm. These mini strain wave gears are ideal for applications such as semiconductor manufacturing and robotics. Available through Electromate.
Learn more.


New technology automatically 'tunes' powered prosthetics while walking

By Matt Shipman, NC State

When amputees receive powered prosthetic legs, the power of the prosthetic limbs needs to be tuned by a prosthetics expert so that a patient can move normally -- but the prosthetic often needs repeated re-tuning. Biomedical engineering researchers at North Carolina State University and the University of North Carolina at Chapel Hill have now developed software that allows powered prosthetics to tune themselves automatically, making the devices more functionally useful and lowering the costs associated with powered prosthetic use.

"When a patient gets a powered prosthetic, it needs to be customized to account for each individual patient's physical condition, because people are different in size and strength. And that tuning is done by a prosthetist," says Helen Huang, lead author of a paper on the work and an associate professor in the biomedical engineering program at NC State and UNC-Chapel Hill. "In addition, people are dynamic -- a patient's physical condition may change as he or she becomes accustomed to a prosthetic leg, for example, or they may gain weight. These changes mean the prosthetic needs to be re-tuned, and working with a prosthetist takes time and money."

To address this problem, the researchers developed an algorithm that can be incorporated into the software of any powered prosthesis to automatically tune the amount of power a prosthetic limb needs in order for a patient to walk comfortably. The algorithm would not only make it easier for patients to walk while reducing prosthetist-related costs, but would also allow a prosthesis to adjust to changing conditions.

"For example, the algorithm could provide more power to a prosthesis when a patient carries a heavy suitcase through an airport," Huang says.

At this stage of development, the system works by taking into account the angle of a prosthetic knee while walking.

Powered prosthetic legs are programmed so that the angle of the prosthetic joints -- the knee or ankle -- while walking mimics the normal movement of the joints when an able-bodied person is walking. During the conventional prosthetic tuning process, a prosthetist adjusts the powered prosthesis' system so that it exerts the power necessary to recreate those normal joint motions while walking.

But changes in a person's weight, or gait, can affect the prosthesis' ability to achieve that "natural" joint angle.

The automatic-tuning algorithm takes a similar approach, tracking the angle of the prosthetic joint while walking. But it is able to adjust the amount of power the prosthesis receives in real time, in order to maintain the proper angle.

"In testing, we found that the computer -- using the algorithm -- performed better than prosthetists at achieving the proper joint angle," Huang says. "So we know our approach works. But we're still working to make it better.

"Prosthetists rely on years of experience to not only adjust the joint angle, but to adjust a prosthesis to help patients maintain a comfortable posture while walking," Huang adds. "We're not yet able to replicate the prosthetist's success in achieving those comfortable trunk motions, but it's something we're working on."

The paper, "A Cyber Expert System for Auto-Tuning Powered Prosthesis Impedance Control Parameters," is published in the journal Annals of Biomedical Engineering. The paper was co-authored by Dustin Crouch, Ming Liu, Gregory Sawicki, and Ding Wang of the joint biomedical engineering program at NC State and UNC-Chapel Hill. The work was supported by the National Science Foundation under grants 1361549, 1406750, and 1527202.

Published October 2015

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