At its Baltimore plant, Allison Transmission, a division of General Motors Corp. (Detroit), employs a rigorous battery of tests to assure critical product tolerances are met for the plant's transmission bodies. These tests-which take place on a workbench separate from the production line-include hundreds of quality checks performed in the course of each shift to the tops and bottoms of a number of different valve bodies and transmission housings.
In the past, due to the complexity of the test, workers would sometimes skip steps to keep up with the company's testing schedule. The process was so arduous it required 3 weeks of training to qualify each operator.
To remedy an unreliable and unwieldy situation, Allison implemented an Apogee Interactive Solutions (AIS) system from Apogee Designs Ltd. (Baltimore), a product initially created to help companies fill vacancies in complicated production lines. Each AIS system includes a computer, AIS software, custom I/O boards and peripherals that are used to create an interactive workstation allowing all assembly and testing processes to be both clearly explained and monitored.
Components can be customized to satisfy a wide range of quality, assembly and training requirements. Supervisors program each station by filling in cells on a Microsoft Excel spreadsheet. AIS software coordinates the interactions between the spreadsheet and components such as lights, motors, tools and gauges. Images and work instructions combined with pick-to-light indicators on tools and part bins greatly reduce the likelihood that an operation is performed incorrectly.
For Allison, the testing workstation now consists of a mounting platen, or fixture, a tool and instrument storage rack, a video monitor, the AIS computer, and a battery of control electronics. Tools, parts and quality instruments are mounted along the sides of the workstation, each with an identifying "use me" LED. The mounting platen holds the assembly and positions it for easy access to areas being tested.
When an assembly is being tested, each step of the procedure is presented visually at its correct time, and the appropriate LED identifies the tool to be used at that point in the test process. Video directions will not advance unless the preceding test is performed and validated. Real-time "go, no-go" or numeric data is displayed at the click of a mouse, and if within range, recorded on the next click. All relevant information along with video documentation can be downloaded to statistical quality control charts or other reports to track short- and long-term trends.
According to Bruce Barnett, body manufacturing and quality engineer at the Allison Baltimore plant, one of the most appealing aspects to the system is the ease of programming whenever there are changes in quality parameters or new products come on-line. "You can walk any individual who has used an Excel worksheet through the process and make changes in minutes," Barnett says.
The new AIS-based process has also improved the company's training regime and the overall effectiveness of its quality control.
"Aside from reducing training time from 3 weeks to 1 day, the system mandates that all steps be performed in the designated order and its internal clock alerts personnel which item is next and when it is due for inspection," Barnett says. "The new system has lifted a huge burden off of our employees and our QA staff. The average testing time has actually increased slightly, giving us assurance that skipped quality steps are now a dead issue."
For more on testing and training systems, call 410-633-6336, visit www.apogeedesigns.com or eInquiry 10.
AIA: Software Smoothes Testing Process
April 1, 2006