Control Engineering's Motors, Drives, and Motion Control Newsletter for November 2001
In this issue:
'Motor Decisions Matter' campaign gains 11 new sponsors
Efficient use of electric energy continues to draw attention, with industrial equipment in the spotlight.
The national campaign to develop an overall management plan for electric motors, known as 'Motor Decisions Matter' was bolstered at the end of October 2001by 10 motor manufacturers and an organization that focuses on improving energy investment returns-Advanced Energy (Raleigh, N.C.). Motor Decisions Matter (MDM) now has 29 sponsors. Comprising the new motor manufacturer sponsors of MDM are A.O. Smith Electrical Products Co., Emerson Motors, GE Industrial Systems, Leeson Electric, Lincoln Motors, Marathon Electric, Rockwell Automation/Reliance Electric, Siemens Energy & Automation, Toshiba, and WEG Electric. Earlier, Baldor Electric Co. was the first motor manufacturer to directly sponsor Motor Decisions Matter.
MDM's motor management plan addresses common motor decisions needed before equipment failure occurs. It helps ensure motor availability, lowers downtime, and reduces energy costs. The Consortium for Energy Efficiency (CEE, Boston, Mass. www.ceeformt.org ) coordinates the campaign. Other sponsors are service centers, electric utilities, government agencies, and trade associations, including EASA and NEMA. For more information, visit MDM's web site at www.motorsmatter.org , and also see July 13, 2001 Daily News at / .
Boosting 'soft motion' control
Software-based and open PC-based motion control-so-called 'soft motion' control-has just recently received a boost from a couple of sources.
On November 5, 2001, Ormec (Rochester, N.Y. www.ormec.com ) introduced ServoWire SM offering control of up to eight servo motion axes directly from a standard PC, using an IEEE-1394 (Firewire) network. ServoWire SM seeks to cut motion system cost and complexity by eliminating the need for proprietary board-level motion controllers and interface hardware, as well as simplifying system wiring. The technology should have an appeal to original equipment manufacturers (OEMs) because they can apply standard Microsoft programming languages (C or C++) and programing/debugging tools (Visual Studio) in their projects.
Firewire supplies high-speed (200 Mbit/sec) communication between the standard PC and distributed ServoWire SM drives comprising a motion system, which can operate in position, velocity, or torque control mode. The servo drives deliver a power range of 0.3-15 kW. Several servo-motor topologies are supported in software: brushless dc (rotary and linear), brush-type dc, and voice coil.
Cimetrix Inc. (Salt Lake City, Ut. www.cimetrix.com ) on October 23 launched CODE 6 (Cimetrix Open Development Environment version 6) with Core Motion technology, a PC-based motion control software package, said to eliminate the need for intelligent motion cards and cut hardware costs by up to 50%. The software places motion card functions onto the PC, allowing it to directly connect to amplifiers and feedback devices. 'This enables the PC software to control trajectory generation, position loop, velocity loop, input/output scanning, and event generation at the servo rate,' according to Cimetrix.
OEM requirements were also the target of CODE 6 with Core Motion. For example, OEMs can scale systems from small to larger size, and keep their custom algorithms in C++ functions to maintain proprietary knowledge.
For more about these items, see Nov. 6 and Oct. 23, 2001 Daily News, respectively, at / .
Motor with a heart
Advances are not all on the production line. Technology casts a wider image when it helps to extend human life or raise its quality. For example, electric motors have had a vital role in the development of medical devices. Here is a recent step forward.
A miniature brushless dc motor runs the pump inside the world's first self-contained artificial heart. To make the unit as compact as possible, the frameless, direct-drive servo motor mounts right to the heart pump in the thoracic unit of AbioCor Implantable Replacement Heart made by Abiomed Inc. (Danvers, Mass. www.abiomed.com ). The totally implantable heart provided a last chance of survival for the patient because of his condition. Kollmorgen (Radford, Va. www.motionvillage.com )-manufacturer of the custom motor measuring about one inch in diameter-had to solve demanding design problems, such as maximizing motor efficiency to prolong battery life, limit temperature rise, and apply only highly corrosion resistant materials.
AbioCor operates automatically from either internal or external lithium batteries. A separate miniaturized electronics unit, implanted in the abdominal region, monitors and controls system performance, including the pumping speed of the heart. The external batteries, worn on a belt, transfer power to the implanted system through the skin using a special TET (transcutaneous energy transmission) device, according to Abiomed. The implanted battery is an emergency power source kept charged continually by the external batteries.
When first implanted in the patient in early July 2001 at Jewish Hospital in Louisville, Ky., doctors forecasted around a 30-day 'endurance' for this innovation. As of November 7, the device was reported doing well and the patient 'better than anticipated.'
So far, five AbioCor systems have been implanted in patients as part of an initial clinical trial conducted under an Investigational Device Exemption from the U.S. Food and Drug Administration. AbioCor has not been approved for commercial distribution.
The North American Promotional Alliance for SERCOS (SErial Realtime COmmunications System) interface reports the availability of a new Conformance Test for three types of SERCOS interface products: controls, servo drives, and I/O stations. This development 'ensures that SERCOS interface products from various manufacturers are compatible and interoperable at the SERCOS Conformance Class A level,' says Ronald Larsen, managing director of SERCOS N.A., (Bloomingdale, Ill. www.sercos.com ). 'Tests to higher conformance classes are in development.'
SERCOS is the standardized, digital interface (IEC 61491) for communication among controls, digital drives, and I/O modules. It is based on a fiberoptic ring with transmission rates up to 16 Mbit/sec.
Conformance testing of SERCOS interface products takes place at Institute for Control Engineering of Machine Tools and Manufacturing Units at the University of Stuttgart, Germany. However, the test software-SERCOS interface Conformizer-is sold as a complete test and development environment to manufacturers for initial in-house testing of their devices. This is intended to minimize the time and cost of passing the formal test.
The software runs under Microsoft Windows NT or 2000, and the package includes more than 80 functions, variables, and I/O programming features. A free demo version and additional user materials can be downloaded form www.isw.uni-stuttgart.de/sercos .
SERCOS was also active with a full-day technical seminar highlighting its technology. The seminar, presented on Nov. 13, 2001 at the SERCOS interface interest group's ( www.sercos.org ) competency center (University of Stuttgart) was directed toward 'development and application engineers who work in the fields of conception, design and application of controls, drives and I/O assemblies based on the SERCOS standard.' Dipl.-Ing, Robert Kynast, head of SERCOS interface's Technical Working Group conducted the seminar. Also see Nov. 2 Daily News at / .
Actuator powered by shape-memory alloys
Shape-memory alloys (SMAs) rather than electromagnetism power NanoMuscle Actuators, an innovative line of linear motion devices offered by NanoMuscle Inc. (Antioch, Calif. www.nanomuscle.com ). Billed as a 'complete motion system,' these actuators consist of a NanoMuscle Motor and a NanoMuscle Interface integrated into a tiny, low-cost package containing all required drive electronics, position sensors, and control logic.
These actuators produce silent, direct linear motion similar to animate muscle movements. Two 'motor' models are presently available for 30 g (1.06 oz) and 70 g (2.5 oz) force outputs. Other typical specs include 4 mm (0.157 in.) stroke, 1-5 million cycle life, and 2-4 V operation. NanoMuscle Actuators target the solenoid devices market, offering superior control capability, repeatable movements, and lower cost.
Telemetry aids motors, motion control
Wireless methods are reaching into all areas of automation and control.
If you need early warning of overheating in dc motor windings, look into Motor Monitor, a new motor maintenance tool from Accumetrics Associates Inc. (Schenectady, N.Y. www.accumetrix.com ). Motor Monitor keeps tabs on as many as eight temperature sensors in the armature windings of industrial dc motors, transmitting digital data from the rotor to a stationary receiver, which displays the temperatures. The receiver alarms the operator if readings exceed preset limits. One current application uses Motor Monitor to explore the extent of overheating permissible without reducing normal service of large dc motors.
Want to measure torque in real-time on actual rotating machinery? Binsfeld Engineering Inc. (Maple City, Mich. www.binsfeld.com ) has introduced an Induction Powered Digital Radio Telemetry System that turns a rotating shaft (up to 4-in. diameter) into a torque sensor. TorqueTrak 9000-IP employs a fiberglass rotating collar with a miniature transmitter that rides on the shaft, broadcasting digital data from a torque-sensitive strain gage to a digital receiver. The system has seven gain settings and eight broadcast frequencies (both user-selectable) and lists at $4,690. This latest product version is an enhancement of battery-powered TorqueTrak 9000 available earlier ( CE, November 2000, p. 108 ).
Info free for the asking
Motor and motion control professionals can benefit from a wealth of information supplied by product manufacturers. Here is another sampling.
Baldor Electric Co. (Fort Smith, Ark. www.baldor.com ) has issued a new 14-page brochure (BR750), describing its SmartMotor integrated induction motors with variable-speed control. The integrated motor/control product line now includes washdown and close-coupled pump (CCP) designs-in addition to C-face and foot-mounted motor styles, up to 10-hp size at 230/460 V input. Dynamic braking is standard on general-purpose and washdown models; optional on CCP designs.
Also available from Baldor at no charge to customers and prospects is a much-improved version 7.0 of CD-ROM Electronic Catalog, providing virtually instant access to 6,500-plus Baldor motors and drives.
ASI Robicon (New Kensington, Pa. www.asirobicon.com ) offers a brochure on its new Active Harmonic Filters, said to eliminate equipment damage caused by voltage harmonics and provide compliance with the harmonics requirements of IEEE 519 standard. The six-page publication includes data and dimensions on various filter models rated at 25-400 A with inputs of 208-600 V ac.
Technical information galore on Baumer Electric Ltd. (Southington, Conn. www.baumerelectric.com ) optical rotary encoders-incremental, absolute, and multi-turn (absolute)-is found in the company's 200-plus page catalog. For example, the expanded absolute multi-turn line supports DeviceNet, CANopen, CAN bus, Interbus, and Profibus networks.
Lo-Cog brush-commutated dc servo motors are profiled in a 20-page product bulletin from Pittman (Harleysville, Pa. www.pittmannet.com ). Bulletin LCM covers specifications and performance data for Lo-Cog Series 8000, 9000, and 14000 motors capable of speeds up to 10,650 rpm and up to 410 oz-in. peak torque.
Companies, organizations in motion
Siemens Energy & Automation Inc. (Alpharetta. Ga. www.sea.siemens.com ) announced in mid-October 2001 the opening of a western region technical center in Cypress, Calif. (Los Angeles area), for the support of its machine tool automation products, specifically CNC, servo, and spindle-drive systems. The new tech center intends to combine OEM sales, application engineering, and field service for Siemens E&A's Motion Control Systems business unit. The company's primary locations for motion control are in Elk Grove Village, Ill., and South Lebanon, O.
'The Motor & Motion Association' is the new name for SMMA (Sherborn, Mass. www.smma.org ). It replaces the organization's original name of Small Motors & Motion Association, but keeps the acronym. The change was recommended by the Board of Directors and approved by SMMA's membership.
Roy-G-Biv Corp. (RGB, Bingen, Wa. www.roygbiv.com ), in late October, partnered with Galil Motion Control (Rocklin, Calif. www.galilmc.com ) to provide its XMC (eXtensions for Motion Control) software products for added connectivity and integration functions in Galil's motion control systems. XMC software from RGB supplies a 'motion middleware' bridge between motion control boards and open PC-based systems, including Internet connectivity. Galil produces motion controllers in PCI, ISA, PC/104 formats, VME board-level products, and stand-alone controllers with RS-232 and Ethernet interfaces.
Earlier, Roy-G-Biv announced that its XMC for OPC software provides direct communications and data exchange between RSView32, an HMI software package from Rockwell Software (Milwaukee, Wis. www.rockwellsoftware.com ) and single or multi-axis motion control systems. XMC for OPC is said to enhance connectivity among Rockwell Software products, Rockwell Automation Logix products, as well as third-party motion control systems.
In September 2001, International Rectifier (El Segundo, Calif. www.irf.com ) opened a new design center for high-voltage integrated circuits (ICs) in Pavia, Italy. The center will focus on R&D work for high-performance, high-voltage motor drive ICs and chipsets intended for industrial motor and servo drives and uninterruptible power supplies.
Danfoss Drives (Loves Park, Ill. www.danfossdrives.com ) has moved into a new 124,000 sq-ft office, testing, and assembly facility here. Danfoss Drives is part of the Motion Controls group and a division of Denmark-based Danfoss A/S Corp.-a leading manufacturer of ac variable-frequency drives. The Drives Division has manufacturing plants in Graasten, Denmark; Rockford, Ill; and Milwaukee, Wis.
Also expanding its facilities, Advanced Motion Controls (AMC, Camarillo, Calif. www.a-m-c.com ) completed construction of its new 86.000 sq-ft world headquarters in late August. The new building will provide more than three times the space of AMC's old site for design, engineering labs, and manufacturing lines. AMC produces PWM servo amplifiers and drives used in robotics and factory-automation systems.
Control Engineering in November
Each in-print issue contains information devoted to motors, drives, and motion control.
My Back to Basics article on 'Types of AC Variable-Speed Drives' discusses the three major approaches-open-loop control, sensorless vector control, and closed-loop flux vector control-plus other variants of this technology.
In November's 'Products & Software' section, Unico Inc.'s (Franksville, Wis.; www.unicous.com ) 2400 Performance Vector Drive incorporates software specifically for test stand and dynamometer applications. Also featured are Goldline Direct Drive Rotary servo motors from Kollmorgen (Radford, Va. www.motionvillage.com ) designed for optional 400 or 480 V operation; and newly introduced MVC Plus Series Medium Voltage Soft Starter manufactured by Motortronics (Clearwater, Fla. www.motortronics.com ) for MV motors in the 2.3-13.8 kV range.