PC-based control reinvigorates lab workhorse

Beyond improving capability, upgrading test stands also requires enhancing their versatility, efficiency, ease of operation, and maintenance. During one recent upgrade, BFGoodrich Aerospace (BFG, Troy, O.) overcame these challenges with help from VMIC (Huntsville, Ala.).BFG designs and manufactures aircraft wheels and brakes.


Beyond improving capability, upgrading test stands also requires enhancing their versatility, efficiency, ease of operation, and maintenance. During one recent upgrade, BFGoodrich Aerospace (BFG, Troy, O.) overcame these challenges with help from VMIC (Huntsville, Ala.).

BFG designs and manufactures aircraft wheels and brakes. The facility features a test lab, which operates special-purpose test stands, such as the Young static test stand or Young Press. Commissioned in the mid-1950s, this dual-axis press applies independently controlled vertical and horizontal loads to the test specimen. Testing requirements imposed by aircraft manufacturers and the FAA recently prompted BFG to upgrade the Young Press so the horizontal axis could statically apply torque to a wheel, brake, or tire assembly.

The torque upgrade meant BFG would also upgrade the machine's controls. The existing manual open-loop controls forced operators to juggle control of both load axes while following test procedures. In fact, a second operator was often required to control parameters, such as tire pressure. The test stand needed automated closed-loop control.

Control aids flexibility

Since long-term objectives required more versatility and faster execution speeds than BFG felt a PLC could deliver, its engineers decided to implement PC-based control. System requirements included execution of automatic control programs, calibration required by frequent transducer substitution, deterministic data sampling, and a graphical user interface (GUI).

IOWorks, VMIC's PC-based control package, met all of BFG's requirements for precise control. To collect, file, save, and communicate dynamometer and other test data, BFG and VMIC also installed a VMEbus system, using an Intel Pentium single-board computer running Microsoft Windows NT, as the new system's architecture. IOWorks, as the control engine, allows programming in either conventional ladder diagrams or C++ code.

VMIC's VMEbus analog-to-digital converter boards send critical test parameters, such as vertical and horizontal loads, torques, and tire pressures to the control system. These boards are accessed with function calls that, when coded into a ladder-logic function block, are nearly transparent to the programmer.

Digital and analog I/O devices are controlled via a Profibus network. The Profibus master is daisy-chained to slave stations. Sensors and actuators are wired to I/O modules on the nearest slave. This configuration reduces wiring and provides flexibility for future upgrades.

The risk of BFG and VMIC's approach has been rewarded by performance beyond initial expectations. Control of critical parameters is very tight with minimal operator intervention. Test requirements are being met more accurately, more quickly, and with less time and labor than previously possible.

"It's a night and day difference. The new setup makes my job much easier. The reliability and repeatability of tests is 10 times better than previous manual controls," says John Yost, BFG's machine operator. "The old system was a kind of balancing act adjusting the control knobs. The new system is much more precise."

For more information, visit www.vmic.com visit www.citect.com ; or visit www.controleng.com/freeinfo .

Author Information

Joseph R. Britton, electrical systems engineer, Test Lab Instrumentation and Facilities, BFGoodrich Aerospace, and Cary D. McCormick, regional sales manager, Industrial Automation, VMIC.

No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Robot advances in connectivity, collaboration, and programming; Advanced process control; Industrial wireless developments; Multiplatform system integration
Sensor-to-cloud interoperability; PID and digital control efficiency; Alarm management system design; Automotive industry advances
Make Big Data and Industrial Internet of Things work for you, 2017 Engineers' Choice Finalists, Avoid control design pitfalls, Managing IIoT processes
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Big Data and bigger solutions; Tablet technologies; SCADA developments
SCADA at the junction, Managing risk through maintenance, Moving at the speed of data
Flexible offshore fire protection; Big Data's impact on operations; Bridging the skills gap; Identifying security risks
click me