LEARN MORE

Zones



Iscar Metals
Assembling the Assembly Systems

A battalion of robots lifting, carrying and joining like soldiers is an impressive image. Perhaps almost as impressive as the effort that goes into creating the system in the first place.

 

The goal at DaimlerChrysler's new minivan plant (to be completed in 2002) is to have 13 basic modules to assemble to make a finished vehicle. Working on the assembly systems for four of those modules is Peak Industries (Dearborn, MI). Actually a second-tier supplier for this project, Peak works most closely with its customer, Advanced Manufacturing Engineering. However, Peak is also a part of weekly meetings at DaimlerChrysler, and is in frequent contact with companies working on other parts of the line.

 

Usually, second tier suppliers don't have so much involvement with the OEM, but these 13 modular components pose several engineering challenges, and DaimlerChrysler wants everything to go as smoothly as possible when production starts up.

Responsible for the automation of installing the instrument panel (IP), rear suspension system, headliner, and seats, the first thing Peak engineers noticed is that the modular systems are pretty large items that have to be wedged into some pretty tight spaces. "These modular systems, like the seats and IP, are bigger than what came before them," says Peak's engineering manager Jeff Miles. "But the opening isn't getting any bigger."

As an example, Miles offer the installation of the front seats. The original proposed assembly system left mere centimeters between the seats and the door. The distance between successful insertion and scratching the finish of the vehicle was too small for DaimlerChrysler, so a new solution has been designed and is in the process of being tested and refined.

Another challenge modularity presents is model variations. Rather than have to try and program different motion sequences for each variation, engineers try to find points of commonality between all models. A good example of this is the Minivan's headliner, which has variations that include a hole for a sunroof, a control panel, and so on. "The hardest part was keeping it simple," observes Miles, "But we think we've found a good solution, and we're building a prototype to test it right now."

The solution is a unit that lifts the headliner lengthwise and inserts it into the vehicle through the windshield. Hard to picture? Imagine a pallet that looks like the big spatulas used to put pizzas in the oven. It scoops up the headliner and puts it in place, holding it there while non-automated assembly units (people) attach the headliner and retract the pallet.

Keeping In Touch

On the average, Peak engineers will work through four of five design iterations in-house before presenting it to the customer. From there, they can count on a few more modifications before they're ready to try out a prototype. This used to be a process that took months, but the growing sophistication of CAD, CAM, CAE, and animated simulation software has helped speed up the process significantly. "Some designs don't even leave the engineer's desk," says Miles. "Since we're designing based on the OEM's CAD files, we can throw unworkable ideas out pretty quickly."

The computer age not only makes it easier to design, redesign, simulate and re-simulate quickly, but also helps communicate these changes back and forth faster. Various electronic data exchange methods (like e-mail and ftp) let Peak stay in nearly constant contact with its customer and with the OEM. "We have access [from DaimlerChrysler] to the CAD drawings of the assemblies we're responsible for, that way any changes they make can be adopted in our CAD drawings," explains Miles.

Taking this one step further, a virtual plant is housed in DaimlerChrysler's system, letting them put all of the components of the assembly line together as they are refined to see if it all works. Not to say that it's an exact match, but it's as close as you can get without being Steven Spielberg.

Reality Check

All of this virtual stuff is great, but there's nothing like the real thing, so once a design has reached the point where everyone thinks it'll work, a prototype is made. The headliner installation module mentioned previously is being prototyped using robotic components and plywood. It will be used to lift prototypes of the headliner into a prototype of the vehicle. If all goes well, Peak will then begin building the actual assembly module.

To do so, Peak will use its own state-of-the-art facility that includes CNC machines, metalforming systems, measurement and inspection equipment, and a final-build and test area where the completed system will be tested one last time before it's shipped out.

From there it will be integrated into DaimlerChrysler's line (once the plant is actually built), and Peak engineers will spend some time on site making sure everything goes well.

(And don't think we've forgotten about the IP, rear suspension, and seat installation systems. We could tell you about them, too. We've been told that they're secret, so then we'd have to kill you.)