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Flexible planetary gearheads: Quiet, extremely robust

FAULHABER GPT gearheads for miniature and micro motors deliver high power density, exceptional flexibility, and excellent cost efficiency. Designed for seamless integration with diverse motors and encoders, these compact planetary drives feature hardened stainless steel components that reliably withstand extreme torques and abrupt load changes. Offered in standard, low-noise, and high-torque variants, they ensure precise, durable performance across wide operating temperature ranges.
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What is a low-waving linear motion guide?

If you are having a problem with your linear guides not always staying perfectly straight during use, it may be due to a phenomenon called waving -- a problem that is particularly critical in high-precision markets such as semiconductor and LCD equipment-related applications or machine tools. Thankfully, THK has an answer.
Read the full article.

NORD serves up sweet energy and cost savings for industrial bakeries

NORD DRIVE-SYSTEMS offers robust, highly configurable drive solutions designed to optimize efficiency, ensure hygiene, and reduce the TCO for automated bakery systems. From industrial-scale mixing and portioning to baking, cooling, and packaging, NORD's modular product portfolio delivers precise, reliable performance across every stage of production.
Read the full article. You may learn something even if you are not in the baking industry.

Key considerations for battery-powered motors

Battery-powered motor applications require careful design considerations to pair motor performance and power consumption profiles in concert with the correct battery type. This Power Electric article covers power requirements, performance considerations, and battery choices to assist you in selecting an efficient motor and a battery with the appropriate capacity. Good technical info.
Read the Power Electric technical article.

Driving next-gen pump and fan applications: Sinamics G210X

The Sinamics G210X is a new frequency converter for advanced pump, fan, and compressor applications, combining easy engineering with robust design. Integrated functions, seamless TIA Portal integration, and a web server reduce PLC effort to speed up commissioning, operation, and diagnostics. IP55 protection, 3C3 coating, and S2 system redundancy ensure reliable operation in demanding environments.
Learn more.

New Exlar food-grade actuator

Curtiss-Wright's Actuation Division has expanded its Exlar line with hygienic electric actuators using FDA-approved materials and finishes. Designed for food, beverage, packaging, and pharmaceutical automation, the new GTF unit enables economical USDA, 3-A, BISSC, and EHEDG certification. Its IP69K washdown option, inverted roller screw, and compact servo-driven design deliver reliable, high-performance motion for hygienic machinery.
Learn more.

New Texas conveyor system is 42 miles long!

SEW-EURODRIVE is helping power one of the most ambitious bulk material handling projects in North America through its contribution to the Dune Express conveyor system, a record-setting 42-mile single-flight conveyor across the Permian Basin.
Read the full article.

Compact servo drives for harsh environs

Built on Copley's proven NanoPlus platform, the compact, 1.2-oz R-Series Nano servo drives withstand extreme temperatures, vibration, shock, and humidity. Available in R47 (CANopen) and R48 (EtherCAT) models, they suit space-constrained, harsh environments such as mil/aero robotics and gimbals. This commercial off-the-shelf series provides a hardened option without defense-specific development lead times.
Learn more from Copley Controls.

Hybrid actuator with force up to 14,726 lb

Kyntronics' new all-electric HyCore hybrid actuator is a compact, low-cost alternative to traditional hydraulic, pneumatic, and electro-mechanical systems. Engineered for OEMs, it delivers up to 14,726 lb of force. The self-contained design eliminates leaks and wear, providing precise control, shock-load tolerance, and high efficiency. It simplifies integration and lowers operating costs for mobile equipment, packaging, assembly automation, and more.
Learn more.

SDP/SI motion products: Best sellers

SDP/SI's best sellers aren't just popular -- they're proven. These are the motion components their customers return to time and again for precision, reliability, and unbeatable value. From belts and pulleys to gears, bearings, and couplings, each product has earned its place through consistent performance in real-world applications.
Learn more and see the full products list.

Automated part grinding and finishing in one unit!

Grinding large fabrications is a classic dull, dirty, and dangerous task perfectly suited for automation, yet traditional setups require multiple costly robots. At Automate 2026, Güdel debuted a single-robot solution that utilizes two extra degrees of freedom to finish massive surfaces without complex part repositioning.
Read the full article.

Rockford RBS ball screws and nuts now available

Automation-Direct now offers US-manufactured RBS ball screws and nuts for precise linear motion in OEM and maintenance applications. Achieving over 90% efficiency, they feature low friction, high accuracy, and minimal wear. Available in various diameters, lengths, and leads, these precision-matched components handle axial loads with minimal backlash, providing a dependable solution that reduces maintenance and extends operational life. Great prices too.
Learn more.

Next-gen conveyor transports 3,000-kg payloads

Building on its established portfolio of twin-strand conveyors that are currently used in a variety of industry verticals, Bosch Rexroth is introducing the TS 7plus transfer system, which is the world's first freely configurable, fully electric conveyance solution to workpieces weighing up to 3,000 kg. TS 7plus transports material via conveyor rollers on freely configurable modular sections with lift/transverse, rotary, and positioning units, as well as stop gates. Great for automotive, battery, aerospace/defense, and more.
Learn more.

Next-generation air bearing linear slide

The A-123 noncontact nanoposi-tioning stage integrates a brushless motor, air bearings, and a 1-nm encoder, supporting 40-kg payloads over 750-mm travel. Its pressurized air film eliminates the friction, wear, and vibration of mechanical stages, ensuring zero particle generation. Customizable with options such as granite bases and isolation systems, it is ideal for semiconductor metrology, inspection, photonics, and more.
Learn more.

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.

What's a unified momentum model? New theory could improve the design and operation of wind farms

Engineers at MIT have developed a comprehensive model that accurately represents the airflow around rotors even under extreme conditions, such as when the blades are operating at high forces and speeds, or are angled in certain directions. [Credit: Image courtesy of the researchers]

 

 

 

 

The first comprehensive model of rotor aerodynamics could improve the way turbine blades and wind farms are designed and how wind turbines are controlled.

By David L. Chandler, MIT

The blades of propellers and wind turbines are designed based on aerodynamics principles that were first described mathematically more than a century ago. However, engineers have long realized that these formulas don't work in every situation. To compensate, they have added ad-hoc "correction factors" based on empirical observations.

Now, for the first time, engineers at MIT have developed a comprehensive, physics-based model that accurately represents the airflow around rotors even under extreme conditions, such as when the blades are operating at high forces and speeds, or are angled in certain directions. The model could improve the way rotors themselves are designed, but also the way wind farms are laid out and operated. The new findings are described in the journal Nature Communications, in an open-access paper by MIT postdoc Jaime Liew, doctoral student Kirby Heck, and Michael Howland, the Esther and Harold E. Edgerton Assistant Professor of Civil and Environmental Engineering.

"We've developed a new theory for the aerodynamics of rotors," Howland says. This theory can be used to determine the forces, flow velocities, and power of a rotor, whether that rotor is extracting energy from the airflow, as in a wind turbine, or applying energy to the flow, as in a ship or airplane propeller. "The theory works in both directions," he says.

Because the new understanding is a fundamental mathematical model, some of its implications could potentially be applied right away. For example, operators of wind farms must constantly adjust a variety of parameters, including the orientation of each turbine as well as its rotation speed and the angle of its blades, in order to maximize power output while maintaining safety margins. The new model can provide a simple, speedy way of optimizing those factors in real time.

"This is what we're so excited about, is that it has immediate and direct potential for impact across the value chain of wind power," Howland says.

Modeling the momentum
Known as momentum theory, the previous model of how rotors interact with their fluid environment -- air, water, or otherwise -- was initially developed late in the 19th century. With this theory, engineers can start with a given rotor design and configuration, and determine the maximum amount of power that can be derived from that rotor -- or, conversely, if it's a propeller, how much power is needed to generate a given amount of propulsive force.

Momentum theory equations "are the first thing you would read about in a wind energy textbook, and are the first thing that I talk about in my classes when I teach about wind power," Howland says. From that theory, physicist Albert Betz calculated in 1920 the maximum amount of energy that could theoretically be extracted from wind. Known as the Betz limit, this amount is 59.3% of the kinetic energy of the incoming wind.

Just a few years later, however, others found that the momentum theory broke down "in a pretty dramatic way" at higher forces that correspond to faster blade rotation speeds or different blade angles, Howland says. It fails to predict not only the amount, but even the direction of changes in thrust force at higher rotation speeds or different blade angles: Whereas the theory said the force should start going down above a certain rotation speed or blade angle, experiments show the opposite -- that the force continues to increase. "So, it's not just quantitatively wrong, it's qualitatively wrong," Howland says.

The theory also breaks down when there is any misalignment between the rotor and the airflow, which Howland says is "ubiquitous" on wind farms, where turbines are constantly adjusting to changes in wind directions. In fact, in an earlier paper in 2022, Howland and his team found that deliberately misaligning some turbines slightly relative to the incoming airflow within a wind farm significantly improves the overall power output of the wind farm by reducing wake disturbances to the downstream turbines.

In the past, when designing the profile of rotor blades, the layout of wind turbines in a farm, or the day-to-day operation of wind turbines, engineers have relied on ad-hoc adjustments added to the original mathematical formulas, based on some wind tunnel tests and experience with operating wind farms, but with no theoretical underpinnings.

Instead, to arrive at the new model, the team analyzed the interaction of airflow and turbines using detailed computational modeling of the aerodynamics. They found that, for example, the original model had assumed that a drop in air pressure immediately behind the rotor would rapidly return to normal ambient pressure just a short way downstream. However, it turns out, Howland says, that as the thrust force keeps increasing, "that assumption is increasingly inaccurate."

And the inaccuracy occurs very close to the point of the Betz limit that theoretically predicts the maximum performance of a turbine -- and therefore is just the desired operating regime for the turbines. "So, we have Betz's prediction of where we should operate turbines, and within 10 percent of that operational set point that we think maximizes power, the theory completely deteriorates and doesn't work," Howland says.

Through their modeling, the researchers also found a way to compensate for the original formula's reliance on a one-dimensional modeling that assumed the rotor was always precisely aligned with the airflow. To do so, they used fundamental equations that were developed to predict the lift of three-dimensional wings for aerospace applications.

The researchers derived their new model, which they call a unified momentum model, based on theoretical analysis, and then validated it using computational fluid dynamics modeling. In follow-up work not yet published, they are doing further validation using wind tunnel and field tests.

Fundamental understanding
One interesting outcome of the new formula is that it changes the calculation of the Betz limit, showing that it's possible to extract a bit more power than the original formula predicted. Although it's not a significant change -- on the order of a few percent -- "it's interesting that now we have a new theory, and the Betz limit that's been the rule of thumb for a hundred years is actually modified because of the new theory," Howland says, "and that's immediately useful." The new model shows how to maximize power from turbines that are misaligned with the airflow, which the Betz limit cannot account for.

The aspects related to controlling both individual turbines and arrays of turbines can be implemented without requiring any modifications to existing hardware in place within wind farms. In fact, this has already happened, based on earlier work from Howland and his collaborators two years ago that dealt with the wake interactions between turbines in a wind farm, and was based on the existing, empirically based formulas.

"This breakthrough is a natural extension of our previous work on optimizing utility-scale wind farms," he says, because in doing that analysis, they saw the shortcomings of the existing methods for analyzing the forces at work and predicting power produced by wind turbines. "Existing modeling using empiricism just wasn't getting the job done," he says.

In a wind farm, individual turbines will sap some of the energy available to neighboring turbines because of wake effects. Accurate wake modeling is important both for designing the layout of turbines in a wind farm, and also for the operation of that farm, determining moment to moment how to set the angles and speeds of each turbine in the array.

Until now, Howland says, even the operators of wind farms, the manufacturers, and the designers of the turbine blades had no way to predict how much the power output of a turbine would be affected by a given change such as its angle to the wind without using empirical corrections. "That's because there was no theory for it. So, that's what we worked on here. Our theory can directly tell you, without any empirical corrections, for the first time, how you should actually operate a wind turbine to maximize its power," he says.

Because the fluid flow regimes are similar, the model also applies to propellers, whether for aircraft or ships, and also for hydrokinetic turbines such as tidal or river turbines. Although they didn't focus on that aspect in this research, "it's in the theoretical modeling naturally," he says.

The new theory exists in the form of a set of mathematical formulas that a user could incorporate in their own software, or as an open-source software package that can be freely downloaded from GitHub. "It's an engineering model developed for fast-running tools for rapid prototyping and control and optimization," Howland says. "The goal of our modeling is to position the field of wind energy research to move more aggressively in the development of the wind capacity and reliability necessary to respond to climate change."

Published September 2024

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