Article tools sponsored by

Technology you can use

By Design News Staff -- Design News, October 25, 2004

See the Light: Laser tracking makes quicker work of painstaking machinery alignments, turning a team task into a solo event. Plus, alignment data goes down on the machine's permanent record.

Portable coordinate measuring system

New device facilitates machine alignment

Once a machine is built, tested, and shipped, it's usually the purview of the field techs, not the designers, to make sure the system is tacked down properly at the customer's locale. Since field techs may not get a chance to read this, being—er, in the field—perhaps you'll pass this on to them the next time you see one.

Laser tracking one day may overshadow traditional aligning by optical transit or wire on some critical installations such as printing presses, says Chuck Pfeffer, a product manager at Faro Technologies Inc. of Lake Mary, FL. The portable coordinate measuring system—which consists of a retro-reflector, the laser tracker itself, tracking software, and a laptop to run it—brings speed and 3D feedback to an aligning job, he says. With laser tracking, a single technician can align a machine in less time than it would take two techs working together to line it up optically.

The retro-reflector, a 11/2 inch diameter sphere, holds three mirrors perpendicularly to each other. Once the technician has set up the laser tracker, he merely moves the retro-reflector to various reference positions on the machine. With a remote control, he instructs the tracker to determine the coordinates and the software to record the measurement. Or, he can let the software guide him between points of interest. He need only be in sight of the tracker and within 230 ft of it to measure points to a 0.001-inch accuracy. The laser measures distance and two angles (azimuth and zenith) for every point.

Of interest to machine designers is the system's ability to generate an installation record of the coordinates. Should trouble crop up later, a technician can shoot new measurements of the machine and compare them against the original coordinates, quickly eliminating a shift in alignment caused by, say, itinerant forklifts—or seismic events, even—as suspects.

CONTACT:Chuck Pfeffer, Faro Technologies Inc.Tel: 407-333-9911; e-mail: pfeffer@faro.comhttp://rbi.ims/ca/3857-500

Extending the Portable Power Budget

New scheme involving ultra-capacitor boost module requires no extra batteries

Average electrical burden in passenger vehicles, cars, and light trucks has escalated in recent years from 500 to 700W and higher. Year-over-year growth in electrical loads is now between 100 and 150W with no end in sight. OEMs maintain that a 14V electrical system can sustain such growth and, moreover, that 14V electrified ancillaries are containable as well. With alternator technology now exceeding 3,000W and currents above 200A, it is incumbent upon the industry to evaluate means to reset the vehicle power budget.

Ultra-Capacitor Boost Modules

The power budget of existing automotive products can be effectively reset with the addition of newly introduced D-Cell ultra-capacitor boost modules. Connected in a bootstrap, or totem pole configuration with the ultra-capacitor on top of the existing VRLA lead-acid battery, the combination electric energy storage system is capable of supporting future electrified power ancillaries while remaining backwards compatible with the existing 12V electrical component base. With this system, OEMs need not completely revise the automobile parts inventory, but simply add new 42V components as needed. The vehicle electrical charging system remains as is with the addition of a small boost converter needed to sustain charge on the D-Cell module.

In this system, a small boost converter maintains charge on the D-cell ultra-capacitor module (Rdlc and Cdlc). The power of the simulation tool Simplorer is exploited in this arrangement to develop the PWM control input to the boost switch from the ultra-capacitor voltage measurement, VMdlc, compared to a setpoint, and this error is used as feedback. Simplorer therefore completes closed-loop control of the boost regulator using only three basic equations. With the alternator and boost omitted from the simulation, the battery and ultra-capacitor respond to the connected loads. Note, the electrical distribution system (EDS) has the capacity to support the 42V bus for a significant time interval.

The Results

The major benefit of the ultra-capacitor bootstrap electric energy storage system as the charging system source for electrified ancillaries is that existing VRLA battery cycling is reduced by 60 percent. This means improved life of the VRLA battery, and better regulation of both the existing 14V EDS bus and the overlay 42V pseudo-PowerNet.

A D-Cell electric energy storage system can source power at much higher efficiency than if a second battery is installed. Under constant power discharge conditions the D-Cell exhibits better than 96 percent efficiency as opposed to the much lower efficiency of a lead acid battery. This in itself is reason for OEMs to give serious consideration to ultra-capacitor technology. Ultra-capacitor technology is expected to reach cost levels of $0.025/F, a point at which the system proposed here begins to fall within the cost targets of automotive systems.

Power Manager: The power budget of existing automotive products can be effectively reset with the addition of newly introduced D-Cell ultra-capacitor boost modules.

• related stories
• resource center
• by this author

 

 

 

• ebm-papst Engineering Solutions

• Beyond the "Black Box"

• A Bailout for U.S. Automakers: Join the Great Debate

• Gadget Freak Case #130: This Gadget Gets the Children up!

• Motors in Small Packages

• Focus on Servo Control

• Distributed Intelligence

• Delivering More for Less

View more articles by Staff Staff

Advertisement

Sponsored Content

Technology Marketplace

Article tools sponsored by

Find a supplier on oemsuppliersearch.com

Talkback

We would love your feedback!

» View All Talkback Threads

» Submit talk back

Advertisement

DN's Resource Center Get Free Information, Made Easy

• Understanding a Modular Instrumentation System for Automated Test
  National Instruments | White Paper
  Request Item
• Advanced Features of High Speed Digital I/O devices : White Paper Series
  National Instruments | White Paper
  Request Item

View More >>

View all DN resources >>