Getting torque-to-inertia right
Crankshafts in running internal-combustion engines pulsate as well as rotate. This pulsation creates both primary and harmonic torsional stress on crankshaft-driven equipment such as superchargers, pumps, alternators, counterbalancers, and shafts...
Flux vector drive review and update
Variable frequency drives convert ac power to dc and then reshape that current to control ac motors. All types control speed by varying current frequency, but one subtype — flux vector drives — uses current-switching techniques to control motor torque as well....
Designing in the right cable features
Engineers designing servo and stepper systems tend to focus on the obvious: the motor, controller, amplifier, and sensors. Signal and power cables, though no less important than the components they connect, are often overlooked until the project's end, or worse, handed off to an electrician without proper training. ...
Designing for high-speed indexing
Manufacturing processes often march to the beat of short repetitive moves. These incremental or indexing cycles are prevalent on all sorts of production machinery, and they frequently hold the key to throughput and productivity. ...
Getting the right angle
Typically, an angle encoder is probably best if an application needs positioning accuracy of 5 angular sec (0.001°) or better and a minimum line count of 10,000 before subdivision...
Coupling selection for servo systems
Choosing the proper servo coupling for an application is a critical part of total system design and greatly affects its overall performance capabilities. For this reason, considering the coupling early in the design process and aligning the coupling performance attributes with the functionality goals of the system can eliminate many problems that typically occur in motion control applications. Each of the couplings we'll discuss here has individual characteristics that make them ideal for many different uses. ...
Considering both steppers and servos
Servomotors are the clear choice for today s motion applications. Then again, so are stepmotors. What s more, stepmotors are also less expensive than they were a few years ago and easier to select, install, and operate. But for that matter, so are servomotors. ...
Applying mechanical limit switches
Limit switches are sensors that provide feedback to keep some physical value (for example, pressure, temperature, or distance) within a preset range. Here we discuss mechanical limit switches and how they sense (and maintain) the position of machine parts. These electromechanical devices are triggered by physical contact, translating mechanical position into electrical responses. For example, on home appliances and automobiles they turn on lights when doors are opened. On manufacturing lines they sequence operations, limit the travel of machine parts, and detect conveyed items. ...
Swims like a fish
Inspired by the efficient swimming motion of the bluegill sunfish, MIT researchers are building a mechanical fin that could one day propel robotic submarines. The propeller-driven submarines, or autonomous underwater vehicles (AUVs), currently perform a variety of functions, from mapping the ocean floor to surveying shipwrecks. But the MIT team hopes to create a more maneuverable, propeller-less underwater robot better suited for military tasks such as sweeping mines and inspecting harbors, and for that they are hoping to mimic the action of the bluegill sunfish....
Semiconductor, packaging drive motion control growth
Thanks to capital expenditures in both the semiconductor and packaging industries, combined with growth in Asia, the general motion control (GMC) outlook is fairly rosy, according to the General Motion Control Worldwide Outlook, a new study from ARC Advisory Group, Dedham, Mass. The globally expanding GMC market is being fueled by greater capabilities and regional expansion, according to the analysts. The worldwide market for GMC systems is forecast to grow at a compounded annual growth rate (CAGR) of roughly 7% over the next five years, to reach $7.8 billion by 2011. ...
Rehab tool makes big strides
Learning to walk the first time around is cute and easy. Having to relearn a basic skill due to a stroke, brain injury, Parkinson's disease, or Multiple Sclerosis is another matter. Thanks to the AutoAmbulator system from HealthSouth Corp., Birmingham, Ala., rehabilitation therapy is now easier than ever for patients and the physical therapists who teach them how to walk again....
New automation company formed
Confero Solutions, King of Prussia, Pa., is a recently established start-up company that is developing advanced precision sensing and motion solutions. Confero designs and builds custom precision sensing and motion systems for OEMs in industries such as semiconductor, electronics manufacturing, life sciences, machine tools, and metrology....
Motor gearbox assembly becomes a star
A custom motor gearbox assembly has made its way into show business as a behind the scenes yet essential costar in "O" by Cirque du Soleil at the Bellagio in Las Vegas. The gearbox assembly is courtesy of Empire Magnetics Inc., Rohnert Park, Calif., and operates as a robust, submersible motion control solution to provide precise, reliable operation of a motorized, battery powered piano...
Motion Control Merger
Minarik Corp., a leading motion control and automation distributor in Glendale, CA, has acquired PacMation Inc. ...
Motion control keeps enemies at bay
From laser-guided bombs to night vision systems, technology advancements help fight terrorists, protect borders, and keep soldiers as safe as possible. As part of this mission, PVP Advanced Electro-Optical Systems Inc., Tustin, Calif., develops and integrates sensors and imaging systems for space, air, ship, and land-based applications that use advanced infrared and image-intensified cameras, lasers, and laser rangefinders. End users include the U.S. military, NASA, Dept. of Homeland Security, as well as aerospace and defense contractors...
