Control systems in a package: going "lean" goes beyond production management. It even affects several aspects of control systems hardware, software, and application development

Automotive Design & Production, Dec, 2006 by Lawrence S. Gould

Running a lean ship in the auto industry is not new. What is new is where that leanness manifests itself. One place is in labor. Because the number of people supporting the production line itself and whatever system(s) sequencing work instructions to the operators on that line has been reduced, there tends not to be an IT support person. Instead, there is a controls person doing two jobs: control systems and IT support. Lean also shows up in production strategy. Make-to-order (MTO) is replacing building to stock and shoving inventory out to dealerships, even though the tools that make MTO possible are still evolving. A third place is in data collection, now very much legitimized by the high warranty and recall costs for products. Information can cut to the chase, enabling automakers to recall the exact vehicles that might be having problems. Then there's the need to protect all these investments in IT and control systems with minimal fuss and expense. Here are some examples of how some controls vendors are helping the auto industry lean out in this realm.

PREPROGRAMMED CONTROL

Bosch Rexroth Corp. (Hoffman Estates, IL; www.boschrexroth-us.com) recently announced plug-and-play control that includes all the necessary hardware and software components--with predefined motion function blocks--for two types of applications: articulated robot pick-and-place and roll feed systems.

IndraMotion for Handling, based on Rexroth's IndraControl L40 motion logic controller, is for Cartesian gantries with up to three linear axes and three rotary axes of motion. This motion is controlled by IEC 61131-based motion function blocks that require a few basic parameters for setup. Depending on what the gantry has to do, between 70% and 90% of the code is basically finished, claims Karl Rapp, automation and machine tool branch manager for Bosch Rexroth, Electric Drives and Controls. Similarly, IndraMotion for Metal Forming has the motion functions for such applications as roll feed, coilers, and traveling cutters. To set up, a user need only enter length, speed, and quantity parameters. This IndraMotion system comes in three versions with differing OEM programming options. One version requires no programming; another lets users program functions blocks to integrate IndraDrives into custom roll feed systems.

The IndraMotion code comes on a CD as "open source." Explains Rapp, the code is finished, but modifiable. "It's not like we compile it and then the user can't do anything with it." The screens are provided as compiled run-time files that can be loaded into Microsoft Windows CE devices, non-CE devices, or PCs. And both IndraMotion packages support SERCOS (fiber and Ethernet), Profibus, and DeviceNet interfaces. "The OEM doesn't have to worry about generating the motion engine or the programming method," continues Rapp. "There's no syntax to learn. Users need only enter, teach, or read the point coordinates from the programmable logic controller [PLC] program or the network connection. All moves are velocity optimized and can be blended. Points can be named so they match the application by simply changing text in the PLC program--no human/machine interface [HMI] change required. The same applies to inputs and outputs, such as grippers."

The benefits are huge. Because the programming methods of the motion itself are standardized, the OEMs only need to focus on the process and integration aspects of their handling or metalworking systems. Engineering and startup times are short. For end users, the standardized programming and troubleshooting methods across all IndraMotion-based systems saves time in installing, training, and maintaining Rexroth-based systems.

MANAGING THE EXECUTION OF CONTROL

Proficy Assembly from GE Fanuc Automation, Inc. (Albany, NY; www.gefanuc.com/en/Industries/Automotive/index.html) for Tier 0.5/1 automotive suppliers is basically a manufacturing execution system (MES) with lean manufacturing components and other built-in capabilities. For instance, in-line sequencing, which responds to OEM broadcasts, releases orders into production and to subassembly feeder lines. Option build data is generated at individual assembly stations. Error proofing capabilities include displaying process steps to the operator; activating pick-to-light; torque control devices, materials handling equipment, and other devices for the operator; and, through appropriate manual, semi-automatic, and automatic feedback, confirming the operator's following of those process steps. Product reporting provides canned reports by line, station, step, and takt time, as well as sending relevant alerts about production. Proficy Assembly will also generate product birth certificates that include the details of each order, its bill of materials (BOM), component serial numbers, process steps and key parameters about production, quality inspections, and any alerts during production.

Here's the kicker, explains Rich Breuning, director of discrete market development for GE Fanuc. OEMs and Tier 1 manufacturer might typically spend millions of dollars for an MES--homegrown or third-party purchase. Instead, turnkey installation of Proficy Assembly is $250,000 per production line (figure 40 to 50 stations). Deployment is expected to take less than six weeks. Typically, such production lines have a PLC for conveyor control with some rudimentary interfaces to pick-to-light bins and some error-proofing equipment, continues Breuning. The PLC remains, but it gets its "marching" orders from Proficy Assembly running on a Dell server. In the very near future, adds Jack Faett, GE Fanuc's director of discrete OEM solutions, the MES will run inside a GE PACSystem server, a controller with a single board computer (SBC). (Points out Faett, there are SBCs just as powerful, if not more powerful, than desktop servers.) The SBC can be put inside an industrialized PC or be part of a VME rack system.