Vehicle painting is one of the critical bottlenecks of automobile assembly lines. Delays on paint lines can adversely affect both throughput and product quality, and increase the amount of wasted material.

Chrysler Corporation has built a custom application that significantly improves productivity at final assembly plants around the world. Chrysler's application for sequencing vehicle production, based on ILOG Optimization Suite, improves production efficiency at 18 Chrysler factories throughout Europe, Mexico and North America by optimally sequencing vehicles through the painting stages of production.

Centralized vehicle scheduler
Chrysler’s new application, the Centralized Vehicle Scheduler (CVS), minimizes the number of times paint needs to be changed in filling customer orders.

The paint area is one of the most critical scheduling zones in a car assembly plant. Whenever a paint color is changed, it must be completely purged from the lines feeding the sprayers, an operation that costs both time and money. With CVS, savings typically run at $12 a purge by reducing cleanup time and conserving paint and solvents. The application has improved purge rates by 10% to 20%, producing annual savings of about $500,000 a plant, or more than $7 million annually for the corporation. Moreover, the automobile maker expects to realize inventory reductions of up to $20 million by using ILOG components in option leveling throughout its production scheduling, achieving a significant improvement in personnel efficiency as well.

Chrysler plans to expand the CVS system to cover other production tasks, including management of vehicle types, options, production and material, plant limitations and numerous other parameters. The ILOG based CVS is expected to eventually support optimal sequencing of vehicles throughout Chrysler's manufacturing process.

Project
The CVS application, based on ILOG Solver, runs on standard PC systems, yet outperforms the previous mainframe based sequencing module. Although the problems CVS addresses are computationally intense, ILOG Solver's powerful and intuitive constraint modeling and solving engine allows Chrysler's master schedulers to configure all relevant parameters and notify production supervisors as required through a simple menu driven interface. The new application remains fully integrated with the existing mainframe package for data input and output.

About Chrysler
Chrysler Corporation is the third-largest manufacturer of passenger cars and light trucks in the US, employing 91,914 people worldwide. Headquartered in Michigan, the company markets vehicles under the Chrysler, Dodge, Eagle, Jeep, and Plymouth brand names, selling about 2.5 million vehicles annually through 7,000 dealers in more than 100 countries.