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Linear guide system corrects misalignments

Bishop-Wisecarver's UtiliTrak^® linear guide system includes vee rails for precision and open rails for misalignment float to provide smooth and accurate motion on inaccurate structures. Because precise parallelism is difficult to achieve, it is not uncommon for mounting surfaces to be slightly out of parallel. UtiliTrak's design compensates for mounting errors and does not require absolute parallelism for accurate operation. Genius.
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Universal Robots emerges as preferred robotics platform for AI solutions at Automate 2024

At North America's largest automation show (Chicago, May 6-9), cobot pioneer Universal Robots will redefine the frontiers of physical AI, showcasing how the "ChatGPT moment for robots" has arrived in a wide range of applications. Automate attendees will also experience how Universal Robots' newest cobot models, the UR20 and UR30, automate tasks with increased payload, reach, and torque.
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Multi-stage mini vacuum pumps: Max performance

Designed to meet the demanding needs of industrial users, the CMS M series mini vacuum pump from COVAL combines robustness, performance, and modularity, offering an optimum solution for applications requiring high suction flow rates, such as gripping porous parts, emptying tanks, or material handling when integrated into vacuum grippers. Thanks to their ultra-compact design and optimized multi-stage Venturi system, these pumps guarantee powerful suction flows up to 19.42 SCFM, while reducing compressed air consumption in a compact footprint.
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Choosing a stepper motor: PM or hybrid?

Lin Engineering stepper motors are widely used in various applications that require precise control of motion, such as in robotics, 3D printing, CNC machines, and medical equipment. There are two main types of stepper motors: permanent magnet (PM) and hybrid. Learn the differences, advantages, and when to use one type or the other.
Read this informative Lin Engineering article.

Top Product: Integrated servo system is 20% smaller than standalone unit

Applied Motion Products has introduced the MDX+ series, a family of low-voltage servo systems that integrate a servo drive, motor, and encoder into one package. This all-in-one drive unit is an ideal solution for manufacturers in logistics, AGV, medical, semiconductor, the solar industries, and many others.
Read the full article.

Overhung load adaptors provide load support and contamination protection

Overhung load adaptors (OHLA) provide both overhung radial and axial load support to protect electrified mobile equipment motors from heavy application loads, extending the lifetime of the motor and alleviating the cost of downtime both from maintenance costs and loss of production. They seal out dirt, grime, and other contaminants too. Zero-Max OHLAs are available in an extensive offering of standard models (including Extra-Duty options) for typical applications or customized designs.
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Why choose electric for linear actuators?

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.
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New AC hypoid inverter-duty gearmotors

Bodine Electric Company introduces 12 new AC inverter-duty hypoid hollow shaft gearmotors. These type 42R-25H2 and 42R-30H3 drives combine an all-new AC inverter-duty, 230/460-VAC motor with two hypoid gearheads. When used with an AC inverter (VFD) control, these units deliver maintenance-free and reliable high-torque output. They are ideal for conveyors, gates, packaging, and other industrial automation equipment that demands both high torque and low power consumption from the driving gearmotor.
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Next-gen warehouse automation: Siemens, Universal Robots, and Zivid partner up

Universal Robots, Siemens, and Zivid have created a new solution combining UR's cobot arms with Siemens' SIMATIC Robot Pick AI software and Zivid's 3D sensors to create a deep-learning picking solution for warehouse automation and intra-logistics fulfillment. It works regardless of object shape, size, opacity, or transparency and is a significant leap in solving the complex challenges faced by the logistics and e-commerce sectors.
Read the full article.

Innovative DuoDrive gear and motor unit is UL/CSA certified

The DuoDrive integrated gear unit and motor from NORD DRIVE-SYSTEMS is a compact, high-efficiency solution engineered for users in the fields of intralogistics, pharmaceutical, and the food and beverage industries. This drive combines a IE5+ synchronous motor and single-stage helical gear unit into one compact housing with a smooth, easy-to-clean surface. It has a system efficiency up to 92% and is available in two case sizes with a power range of 0.5 to 4.0 hp.
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BLDC flat motor with high output torque and speed reduction

Portescap's 60ECF brushless DC slotted flat motor is the newest frame size to join its flat motor portfolio. This 60-mm BLDC motor features a 38.2-mm body length and an outer-rotor slotted configuration with an open-body design, allowing it to deliver improved heat management in a compact package. Combined with Portescap gearheads, it delivers extremely high output torque and speed reduction. Available in both sensored and sensorless options. A great choice for applications such as electric grippers and exoskeletons, eVTOLs, and surgical robots.
Learn more and view all the specs.

Application story: Complete gearbox and coupling assembly for actuator system

Learn how GAM engineers not only sized and selected the appropriate gear reducers and couplings required to drive two ball screws in unison using a single motor, but how they also designed the mounting adapters necessary to complete the system. One-stop shopping eliminated unnecessary components and resulted in a 15% reduction in system cost.
Read this informative GAM blog.

Next-gen motor for pump and fan applications

The next evolution of the award-winning Aircore EC motor from Infinitum is a high-efficiency system designed to power commercial and industrial applications such as HVAC fans, pumps, and data centers with less energy consumption, reduced emissions, and reduced waste. It features an integrated variable frequency drive and delivers upward of 93% system efficiency, as well as class-leading power and torque density in a low-footprint package that is 20% lighter than the previous version. Four sizes available.
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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.
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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.

New method rapidly verifies that a robot will avoid collisions

Faster and more accurate than some alternatives, this approach could be useful for robots that interact with humans or work in tight spaces.

By Adam Zewe, MIT

Before a robot can grab dishes off a shelf to set the table, it must ensure its gripper and arm won't crash into anything and potentially shatter the fine china. As part of its motion planning process, a robot typically runs "safety check" algorithms that verify its trajectory is collision-free.

However, sometimes these algorithms generate false positives, claiming a trajectory is safe when the robot would actually collide with something. Other methods that can avoid false positives are typically too slow for robots in the real world.

Now, MIT researchers have developed a safety check technique that can prove with 100% accuracy that a robot's trajectory will remain collision-free (assuming the model of the robot and environment is itself accurate). Their method, which is so precise it can discriminate between trajectories that differ by only millimeters, provides proof in only a few seconds.

But a user doesn't need to take the researchers' word for it -- the mathematical proof generated by this technique can be checked quickly with relatively simple math.

The researchers accomplished this using a special algorithmic technique, called sum-of-squares programming, and adapted it to effectively solve the safety-check problem. Using sum-of-squares programming enables their method to generalize to a wide range of complex motions.

This technique could be especially useful for robots that must move rapidly to avoid collisions in spaces crowded with objects, such as food preparation robots in a commercial kitchen. It is also well suited for situations where robot collisions could cause injuries, like home health robots that care for frail patients.

"With this work, we have shown that you can solve some challenging problems with conceptually simple tools. Sum-of-squares programming is a powerful algorithmic idea, and while it doesn't solve every problem, if you are careful in how you apply it, you can solve some pretty nontrivial problems," says Alexandre Amice, an electrical engineering and computer science (EECS) graduate student and lead author of a paper on this technique.

Amice is joined on the paper fellow EECS graduate student Peter Werner and senior author Russ Tedrake, the Toyota Professor of EECS, Aeronautics and Astronautics, and Mechanical Engineering, and a member of the Computer Science and Artificial Intelligence Laboratory (CSAIL). The work will be presented at the International Conference on Robots and Automation.

Certifying safety
Many existing methods that check whether a robot's planned motion is collision-free do so by simulating the trajectory and checking every few seconds to see whether the robot hits anything. However, these static safety checks can't tell if the robot will collide with something in the intermediate seconds.

This might not be a problem for a robot wandering around an open space with few obstacles, but for robots performing intricate tasks in small spaces, a few seconds of motion can make an enormous difference.

Conceptually, one way to prove that a robot is not headed for a collision would be to hold up a piece of paper that separates the robot from any obstacles in the environment. Mathematically, this piece of paper is called a hyperplane. Many safety-check algorithms work by generating this hyperplane at a single point in time. However, each time the robot moves, a new hyperplane needs to be recomputed to perform the safety check.

Instead, this new technique generates a hyperplane function that moves with the robot, so it can prove that an entire trajectory is collision-free rather than working one hyperplane at a time.

The researchers used sum-of-squares programming, an algorithmic toolbox that can effectively turn a static problem into a function. This function is an equation that describes where the hyperplane needs to be at each point in the planned trajectory so it remains collision-free.

Sum-of-squares can generalize the optimization program to find a family of collision-free hyperplanes. Often, sum-of-squares is considered a heavy optimization that is only suitable for offline use, but the researchers have shown that for this problem it is extremely efficient and accurate.

"The key here was figuring out how to apply sum-of-squares to our particular problem. The biggest challenge was coming up with the initial formulation. If I don't want my robot to run into anything, what does that mean mathematically, and can the computer give me an answer?" Amice says.

In the end, like the name suggests, sum-of-squares produces a function that is the sum of several squared values. The function is always positive, since the square of any number is always a positive value.

Trust but verify
By double-checking that the hyperplane function contains squared values, a human can easily verify that the function is positive, which means the trajectory is collision-free, Amice explains.

While the method certifies with perfect accuracy, this assumes the user has an accurate model of the robot and environment; the mathematical certifier is only as good as the model.

"One really nice thing about this approach is that the proofs are really easy to interpret, so you don't have to trust me that I coded it right because you can check it yourself," he adds.

They tested their technique in simulation by certifying that complex motion plans for robots with one and two arms were collision-free. At its slowest, their method took just a few hundred milliseconds to generate a proof, making it much faster than some alternate techniques.

While their approach is fast enough to be used as a final safety check in some real-world situations, it is still too slow to be implemented directly in a robot motion planning loop, where decisions need to be made in microseconds, Amice says.

The researchers plan to accelerate their process by ignoring situations that don't require safety checks, like when the robot is far away from any objects it might collide with. They also want to experiment with specialized optimization solvers that could run faster.

"Robots often get into trouble by scraping obstacles due to poor approximations that are made when generating their routes. Amice, Werner, and Tedrake have come to the rescue with a powerful new algorithm to quickly ensure that robots never overstep their bounds, by carefully leveraging advanced methods from computational algebraic geometry," adds Steven LaValle, professor in the Faculty of Information Technology and Electrical Engineering at the University of Oulu in Finland, who was not involved with this work.

This work was supported, in part, by Amazon and the U.S. Air Force Research Laboratory.

Published April 2024

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