Leica Geosystems Takes the Measure of Ford Motor Co.
Leica Geosystems' LTD700 PCMM

W hen Ford Motor Co. found itself in need of upgraded measurement solutions for its major North American assembly plants, it turned to Leica Geosystems' Metrology Division, headquartered in Underentfelden, Switzerland.

Ford faces the same issues that all automakers face--making accurate measurements quickly, particularly for large sheet metal and tooling pieces. The problem was how to measure these parts in place without moving either the part or the meas--uring instrument.

Although suitable for small-volume work, articulated arms for inspecting large tooling didn't yield the accuracy automakers look for due to leapfrog measuring and data alignment issues. The arms would capture many relative point locations, but no absolute positions to the overall 3-D coordinate tooling system.

Laser tracking technology ushered in many advantages with its large measurement volume capability that could capture the entire automobile envelope within three or four station relocations around the tooling. The accuracy was dead-on, and the data captured were absolute to the global coordinate system of the measured tooling. But there were still line-of-sight issues, and time-consuming station relocations.

Leica studied the interactions on the shop floor of Ford and automakers around the world. Their research and development provided the basis for creating a new product--the T-Probe--that would not only facilitate the large measurement volume required by the auto industry but also double the productivity level. The T-probe, both wireless and armless, in conjunction with a laser tracker, allows an inspector to roll the laser tracking system up to the geostation and measure the entire volume of automotive tooling from a single location, instead of three or four relocations. Early benchmarks showed nearly a 50-percent increase in time savings for tooling inspection alone.

Ford purchased its first Leica laser trackers in 2002, with full implementation beginning in 2003. In June of this year, Ford placed an upgrade order for 17 T-Probes, 17 Metrolog XG software suites and six additional Leica laser trackers for industrial measurement applications. All 28 of Ford's current laser tracker systems will be upgraded to the T-Probe/Metrolog XG configuration in the coming years.

The LTD700 has a variety of applications for Ford. In its assembly plants, the LTD700 is used to check and certify weld tools and fixtures. The laser trackers are also utilized for pallet inspection, troubleshooting sheet-metal issues and general body-in-white problem solving. In Ford's prototyping plants, the LTD700s are used in a similar fashion, including build-up and certification of prototype tooling and sheet metal. In Ford's stamping facilities, the Leica laser trackers are deployed for die and sheet metal inspection. These various and important quality assurance functions point to the versatility and flexibility of Leica's LTD700 solution.

The T-Probe is particularly well-suited to the demanding shop floors found in automotive manufacturing and assembly. The shock-resistant probing device is highly accurate and has a large measurement volume. It offers six degrees of freedom, allowing engineers and metrologists to measure deep inside parts and tooling.

Leica's LTD700 system (accompanied by the T-Probe) met Ford's high accuracy and reliability requirements for industrial measurement. The laser trackers have had minimal downtime since their installation. The overall system functionality presented many key user benefits, including ease of use, quick setup times, rapid measurement capabilities and robust software. The portable nature of the system is a greatly beneficial feature as well.

"In a nutshell, the T-probe has transformed the Leica laser tracker from being a good metrology tool to the ideal tool for the automotive industry," says Joel Martin, an industrial measurement specialist for Leica Geosystems' Metrology Division. "Measuring and recording data on the fly from large assemblies and tooling is at the top of the automotive quality inspector's wish list. On-demand inspection requires solutions that are responsive to an industry's environment and create the least amount of impact to others working in the same environment."

Leica Geosystems' LTD700 PCMM

Benefits:

• Leica's laser tracker combines with Metrolog XG software and the T-Probe to greatly expand meas-
  urement capabilities.
• The LTD700 has the fastest meas-
  urement cycle in the industry (3,000 points/second) with a measurement volume of 40 meters, a 360-degree range in the horizontal axis and a
  90-degree range in the vertical.
• The T-Probe offers accuracy of 0.06 mm in a measurement volume of up to 14 meters, with six degrees of freedom.
• The system offers great ease of use, quick setup times, rapid meas-
  urement capabilities, robust software options and portability.

www.leica-geosystems.com