DiamlerChrysler Robot Swap

The following is from an article that appeared in Robotics World magazine.

Simulation/Offline Programming

Applied Manufacturing Technologies (AMT) began using ROBCAD for simulation and off-line programming of robotic cells in 1992. During the first few years of use of ROBCAD, AMT staff developed particular expertise in off-line programming of robotic paint cells where tolerances for position accuracy are not so demanding. A few years ago, in an effort to extend the use of off-line programming to welding and other applications, AMT investigated solutions using calibration systems and selected Dynalog Inc. as the calibration vendor AMT recommends for their off-line programming customers for many applications.

DaimlerChrysler JR Program – Robot Swap at SHAP
Recently, in anticipation of the launch of the JR program at the Sterling Heights Assembly Plant (SHAP), DaimlerChrysler's Advance Manufacturing Engineering group enlisted AMT and Dynalog to perform two types of robot program transfers:

• Robot Swap: the transfer of existing production robot programs to new robots being installed at the plant; and
• Robot Cell Cloning: the transfer of existing production robot programs between parallel production lines at the plant.

Both the Robot Swap and Robot Cell Cloning tasks were scheduled on a rolling basis to minimize production interruption by performing the tasks during weekend down-time. As a result, the time required to physically remove the existing robots and then commission the new robots left very little time for programming of the new robots yet the current production cycle time had to be maintained!

As Dennis Archer of DaimlerChrysler's Advance Manufacturing Engineering stated at the 1999 NASCAPE Conference in Detroit, "We know that definitions of off-line programming vary throughout our industry. Our definition is quite simple: no 'touch up' with the teach pendant. The SHAP situation, as in any launch situation, required that we keep production interruption to an absolute minimum. Speed and accuracy of the calibration process were critical to our success. Because of the unique circumstances of our Robot Swap [between robots produced by different vendors], it was essential that we minimize risk by leveraging our past experience, DaimlerChrysler's and AMT's, off-line programming thousands of the "old" and "new" robots using Tecnomatix' ROBCAD software and Dynalog's DynaCal™ System." 

Description of the Swap and Cloning Process
The SHAP SWAP project required more than a download of a robot program created in simulation to the "new" robot. The project required a means to "upload" existing production robot programs from the "old" robot (JA vehicle program) to the simulation environment. In the simulation environment the "new" robot could be inserted in place of the old robot in order to generate a robot program ready to run on the "new" robot.

Of course as two different robot manufacturers built the robots, a language translator was required to insure that the new robots could execute production robot programs for both the existing JA and the upcoming JR vehicle programs. So, Archer created a language translator using ROBCAD's ROSE environment, to convert the production robot programs from the old robot language to the new robot language.  

Process Description

• Calibrate 'Old' Robot Cell (Robot, End-Effector, and Fixture) with DynaCal System.
• 'Reverse' Filter production robot program with DynaCal System and Upload to ROBCAD environment.
• Replace 'Old' Robot Model for 'New' Robot Model in ROBCAD environment.
• Calibrate 'New' Robot Cell with DynaCal System.
• Download production robot program from ROBCAD System and ‘Forward’ Filter with DynaCal System.
• Execute production robot program on the ‘New’ Robot.

ROBCAD Saves Time and Money
More than 50 robots programmed without manual ‘touch-up’. Robot programming time on the plant floor reduced by more than 80 percent. Robot Swap completed within 2.5 hours (including calibration of both robot cells). Robot Cell Cloning completed within 30 minutes. A single ‘nominal’ production robot program maintained across parallel lines.