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Versatile Transport System: Turbocharge conveyance

THK's Versatile Transport System is a high-mix production solution that will keep your production line moving. Its linear motor drive enables high-speed operations, and processing can be performed directly on top of the system's freely recirculating sliders. This highly precise, modular system has many unique features, including easily adjustable stop positions, flex layouts with path splitting and parallelization, and easy addition/subtraction of extension pieces.
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Tech Tip: How to keep heavy loads balanced

Some Thomson smart linear actuators have a position-based synchro-nization option to help manage unbalanced loads when using multiple units. The system adjusts the speed of each actuator to keep them starting, moving, and stopping synchronously, regardless of their respective load distribution. So useful. So smart.
Learn all about this feature.

Micropositioning stages ensure high accuracy

PI now offers fast delivery of the L-511 linear microposi-tioning stage, which is designed for applications requiring minimum incremental motion down to 20 nm and drive forces up to 22 lb. The L-511 can be combined to form XY or XYZ motion systems and integrated with rotary stages for enhanced flexibility. Features high-load recirculating ball bearings for exceptional durability, even under demanding, repetitive cycles. To enhance positioning accuracy and automation throughput, this stage integrates non-contact, direction-sensing optical reference point switches located at mid-travel.
Learn more.

Robots think and act on the fly at moving assembly line speeds

Inbolt and FANUC are launching a manufacturing breakthrough enabling FANUC robots to tackle one of the most complex automation challenges: performing production tasks on continuously moving parts at line speeds. With Inbolt's AI-powered 3D vision, manufacturers can now automate screw insertion, bolt rundown, glue application, and other high-precision tasks on parts moving down the line without costly infrastructure investments or cycle time compromises.
Learn more.

Best high-speed rotary bearing in THK history

THK has developed its best-performing, high-speed rotary bearing ever: the High-Speed, Double-Row Angular Contact Ring BWH. This rotary bearing has balls aligned inside a cage between the inner and outer rings and is part of the THK Rotary Series, along with the cross-roller ring. The main features of this product are its ability to receive loads in all directions as well as its high rigidity and rotational accuracy, which are equal to that of cross-roller rings. By adopting a new structure to change the rolling elements from rollers to balls, this product achieves the greatest high-speed performance ever offered by THK.
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Elevating tables: Precise vertical positioning in tight spaces

As semicon-ductors and optical components become smaller and more sophisticated, the TZ Series of precision elevating tables from IKO International provides exceptional vertical positioning accuracy in a compact size. This unit features a unique wedge mechanism guided in the vertical direction by a pair of IKO C-Lube Super MX linear motion rolling guides arranged in parallel to achieve highly precise positioning with exceptional rigidity. An optional linear encoder provides full closed loop control to achieve positioning accuracy as high as 0.005 mm, with repeatability of +/-0.001 mm.
Learn more and get all the specs.

This cobot is all about safety around people

The COBOTTA PRO from DENSO Robotics is a lightweight, high-speed collaborative robot designed for communication between workers and robots while maximizing productivity. It delivers a blend of productivity and safety for both simple tasks and multi-step processes like assembly and inspection work. The 6-axis unit operates at speeds up to 2,500 mm per sec when no workers are near and slows or stops when people approach. Two models available: PRO 900 (max payload 6 kg) and PRO 1300 (max payload 12 kg). Many more functions and features.
Learn more.

Powerful, pull-type clapper solenoids handle myriad jobs

New powerful, low-profile, pull-type clapper solenoids are available from Magnetic Sensor Systems (MSS). Applications include valve control, locks, starters, ventilators, clamping, sorting, appliances, tools, HVAC, brakes, clutches, switches, mixing, fire suppression systems, door controls, detent latches, and more. The S-16-264 Series of 17 Pull-Type Clapper Solenoids have ampere turns (windings) adjusted to meet the specific force and duty cycle requirements of your application. They provide up to 130 lb (578 N) of force.
Get all the specs for these solenoids and other options.

Tech Tip: Belt, screw, or chain-driven actuator?

Bishop-Wisecarver provides a quick, very useful guide to help you evaluate the right drive strategy for your system: belt, screw, or chain-driven actuator. Each drive type has unique advantages and limitations, so evaluating all your options will help you find the most suitable actuator setup for your specific application needs.
Read the Bishop-Wisecarver blog.

Ultra-precise linear stage -- down to 0.005 microns

PI, a global leader in precision motion control and nanoposi-tioning, now offers fast delivery of the L-511 linear micropositioning stage, which is designed for applications requiring minimum incremental motion down to 20 nm, drive forces up to 22 lb, and multi-axis configuration options. The L-511 can be combined to form XY or XYZ motion systems and integrated with rotary stages. A variety of drive and encoder options (stepper and servo motors, rotary, and linear encoders) enable ultra-fine sensitivity. Applications include: metrology, laser processing, semiconductors, biotech, optical alignment, and advanced automation.
Learn more and get all the specs.

Choosing the right stepper motor: PM or hybrid?

According to the experts at Lin Engineering, there are two primary types of stepper motors to consider: permanent magnet (PM) and hybrid. But which is right for your application? Both types have their advantages and disadvantages, and the choice ultimately depends on your specific requirements.
Read this informative Lin Engineering article.

New PTFE-free linear guide for precise positioning

The new drylin WWP linear guide from igus features a PTFE-free locking carriage. Engineered from lubrication-free, high-performance polymers and aluminum, the guide offers a lightweight, hygienic, and low-maintenance alternative to complex mechanical and electronic adjustment systems. It is significantly more compact and lightweight than conventional recirculating ball-bearing systems. Applications include interior components in vehicles, aircraft, and furniture.
Learn more and get all the specs.

Heavy-duty gear units for mixing and agitating systems

MAXXDRIVE industrial gear units from NORD DRIVE-SYSTEMS are an established drive solution for heavy-duty applications. In addition to conveying, lifting, and driving, they also play an important role in mixing and agitating systems. MAXXDRIVE units feature a compact, one-piece UNICASE housing that delivers long service life, easy maintenance, and quiet operation. Their robust design handles high axial and radial loads, achieves output torques up to 2,495,900 lb-in., and powers up to 8,075 hp.
Learn more.

What are non-captive linear actuators?

According to PBC Linear, their new non-captive linear actuators are different from the more common external versions of lead screw-driven linear actuators because they allow the lead screw to completely pass through the motor. This fundamental difference offers advantages for designs that have limited space available or for engineers looking to shrink the overall size of their design package.
Read the full PBC Linear blog.

Güdel introduces Swiss-quality tracks for cobots

Güdel Inc. is highlighting new technologies at Automate 2025 booth #2418 that demonstrate its unmatched ability to solve automation engineering challenges. One is the Cobomover, a 7th-axis linear track purpose-built for collaborative and lightweight robots. Designed and manufactured in Switzerland, this unit extends the working range of robots up to 5 m, allowing them to operate multiple workstations and perform a variety of tasks without manual repositioning. Compatible with over 60 cobots and small traditional robots.
Learn more and get all the specs.

Computer vision challenger: RFID tags provide new way for robots to track moving objects with unprecedented precision

By Rob Matheson, MIT

A novel system developed at MIT uses RFID tags to help robots home in on moving objects with unprecedented speed and accuracy. The system could enable greater collaboration and precision by robots working on packaging and assembly, and by swarms of drones carrying out search-and-rescue missions.

In a paper presented at the USENIX Symposium on Networked Systems Design and Implementation in February 2019, the researchers show that robots using the system can locate tagged objects within 7.5 msec, on average, and with an error of less than a centimeter.

In the system, called TurboTrack, an RFID (radio-frequency identification) tag can be applied to any object. A reader sends a wireless signal that reflects off the RFID tag and other nearby objects, and rebounds to the reader. An algorithm sifts through all the reflected signals to find the RFID tag's response. Final computations then leverage the RFID tag's movement -- even though this usually decreases precision -- to improve its localization accuracy.

MIT Media Lab researchers are using RFID tags to help robots home in on moving objects with unprecedented speed and accuracy, potentially enabling greater collaboration in robotic packaging and assembly and among swarms of drones. [Photo courtesy of the researchers]

 

 

 

 

The researchers say the system could replace computer vision for some robotic tasks. As with its human counterpart, computer vision is limited by what it can see, and it can fail to notice objects in cluttered environments. Radio frequency signals have no such restrictions: They can identify targets without visualization, within clutter, and through walls.

To validate the system, the researchers attached one RFID tag to a cap and another to a bottle. A robotic arm located the cap and placed it onto the bottle, held by another robotic arm. In another demonstration, the researchers tracked RFID-equipped nanodrones during docking, maneuvering, and flying. In both tasks, the system was as accurate and fast as traditional computer-vision systems, while working in scenarios where computer vision fails, the researchers report.

"If you use RF signals for tasks typically done using computer vision, not only do you enable robots to do human things, but you can also enable them to do superhuman things," says Fadel Adib, an assistant professor and principal investigator in the MIT Media Lab, and founding director of the Signal Kinetics Research Group. "And you can do it in a scalable way, because these RFID tags are only 3 cents each."

In manufacturing, the system could enable robot arms to be more precise and versatile in, say, picking up, assembling, and packaging items along an assembly line. Another promising application is using handheld "nanodrones" for search-and-rescue missions. Nanodrones currently use computer vision and methods to stitch together captured images for localization purposes. These drones often get confused in chaotic areas, lose each other behind walls, and can't uniquely identify each other. This all limits their ability to, say, spread out over an area and collaborate to search for a missing person. Using the researchers' system, nanodrones in swarms could better locate each other, for greater control and collaboration.

"You could enable a swarm of nanodrones to form in certain ways, fly into cluttered environments and even environments hidden from sight, with great precision," says first author Zhihong Luo, a graduate student in the Signal Kinetics Research Group.

The other Media Lab co-authors on the paper are visiting student Qiping Zhang, postdoc Yunfei Ma, and Research Assistant Manish Singh.

Super resolution
Adib's group has been working for years on using radio signals for tracking and identification purposes, such as detecting contamination in bottled foods, communicating with devices inside the body, and managing warehouse inventory.

Similar systems have attempted to use RFID tags for localization tasks. But these come with tradeoffs in either accuracy or speed. To be accurate, it may take them several seconds to find a moving object; to increase speed, they lose accuracy.

The challenge was achieving both speed and accuracy simultaneously. To do so, the researchers drew inspiration from an imaging technique called "super-resolution imaging." These systems stitch together images from multiple angles to achieve a finer-resolution image.

"The idea was to apply these super-resolution systems to radio signals," Adib says. "As something moves, you get more perspectives in tracking it, so you can exploit the movement for accuracy."

The system combines a standard RFID reader with a "helper" component that's used to localize radio frequency signals. The helper shoots out a wideband signal comprising multiple frequencies, building on a modulation scheme used in wireless communication, called orthogonal frequency-division multiplexing.

The system captures all the signals rebounding off objects in the environment, including the RFID tag. One of those signals carries a signal that's specific to the specific RFID tag, because RFID signals reflect and absorb an incoming signal in a certain pattern, corresponding to bits of 0s and 1s, that the system can recognize.

Because these signals travel at the speed of light, the system can compute a "time of flight" -- measuring distance by calculating the time it takes a signal to travel between a transmitter and receiver -- to gauge the location of the tag, as well as the other objects in the environment. But this provides only a ballpark localization figure, not subcentimeter precision.

Leveraging movement
To zoom in on the tag's location, the researchers developed what they call a "space-time super-resolution" algorithm.

The algorithm combines the location estimations for all rebounding signals, including the RFID signal, which it determined using time of flight. Using some probability calculations, it narrows down that group to a handful of potential locations for the RFID tag.

As the tag moves, its signal angle slightly alters -- a change that also corresponds to a certain location. The algorithm then can use that angle change to track the tag's distance as it moves. By constantly comparing that changing distance measurement to all other distance measurements from other signals, it can find the tag in a three-dimensional space. This all happens in a fraction of a second.

"The high-level idea is that, by combining these measurements over time and over space, you get a better reconstruction of the tag's position," Adib says.

"The work reports sub-centimeter accuracy, which is very impressive for RFID," says Lili Qiu, a professor of computer science at the University of Texas at Austin whose research focuses on wireless networking and communications. "The paper proposes an interesting idea that lets a ‘helper' transmit a wideband signal compatible with RFID protocol to achieve high tracking accuracy [and] develops a … framework for RF localization that fuses measurements across time and across multiple antennas. The system has potential to support [the researchers'] target applications, such as robotic assembly and nanodrones. … It would be very interesting to see the field test results in the future."

The work was sponsored, in part, by the National Science Foundation.

Published March 2019

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