The new E4Q energy chain from igus can be opened and closed in seconds without tools and has been specifically developed for the special requirements of unsupported lengths and long travels. igus, the Germany-based manufacturer of motion plastics, unveiled a prototype of the new E4Q in April at Hannover Messe. The chain links have a […]
Linear drives (all)
Linear “lineup” impressive for Robotic Summit in June: Attend for technology insights
Robots aren’t all humanoid and SCARA; some take the form of linear-motion arrangements. In fact, we’ve covered how Cartesian arrangements in particular offer better energy efficiency and price points than more stereotypical robotic arrangements. You’ll get copious amount of information on such linear designs and technologies at the 2019 Robotics Summit (on commercial-robotics design, development, […]
What are planar errors and how do they affect the accuracy of a linear motion system?
In an ideal world, a linear motion system would exhibit perfectly flat, straight motion and reach the intended position with zero error every time. But even the highest precision linear guides and drives (screws, rack and pinions, belts, linear motors) have some errors due to machining tolerances, handling, mounting, and even the manner in which […]
How to measure synchronous (toothed) belt tension
Updated June 2019 || One of the benefits of synchronous belts is their ability to operate with lower tension than their V-belt counterparts. And once the proper tension is determined and applied, synchronous belts rarely need re-tensioning. But improper tension in a synchronous belt drive system — either too low or too high — can […]
When do synchronous belts need flanged pulleys?
Synchronous belts transmit power via positive engagement between profiled teeth on the belt and pulley. Although this tooth engagement (along with proper belt tension) prevents the belt from ratcheting, the belt is free to track, or move side-to-side, on the pulley. To prevent the belt from riding off the pulley, and to resist the lateral […]
Update on roller-screw actuator design and applications (with video and image galleries)
Roller screws are also called planetary roller screws or sometimes satellite roller screws for how their nut-encased rollers orbit the drive-shaft axis during operation. These mechanical rotary-to-linear devices work in an increasing number of electromechanical actuators. Satellite roller-screw geometry includes far more internal contact between load-bearing subcomponents than their ballscrew cousins, and that boosts rigidity […]
Mechanical properties of materials: Shafts in torsion
Power transmission shafts — on motors and gearboxes, for example — are subjected to torque loads that result in torsion, or twisting of the shaft about its axis. Similar to structures under tension or compression, two important mechanical properties of shafts under torque loads are shear stress and shear strain. Stress is a material’s resistance […]
Application example: Ladders on construction machinery use actuators for better ergonomics
90% of small U.S. construction companies have safety programs, but only a third have programs to improve the ergonomics of workers’ environments. It’s too bad, because the risk of musculoskeletal disorders (MSDs) is especially high in construction workers. Plus annual wage and salary losses are estimated at $46 million for the U.S. private-construction sector. Workers […]
How to size a rack and pinion drive
In linear motion applications, ball screws are widely recognized for their ability to provide high thrust forces, while linear motors are gaining market share in high-speed applications, and belt drives continue to maintain their reputation as the best solution for long travel lengths. But rack and pinion drives are the often-overlooked workhorses behind gantry and […]
Ball screw standards: What you need to know about DIN, ISO, and JIS
If you’re involved in ball screw sizing or selection, you’ve probably noticed that there are several different standards that govern various aspects of ball screw design, from lead accuracy and load capacity to ball nut tolerances and rigidity. Fortunately, in many cases, these standards are in harmony and provide the same (or virtually equivalent) specifications. […]