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Stäubli RX robots are simulating the actions of vehicle drivers to test the reliability of satellite navigation equipment at Siemens Automotive AG, Regensberg factory in Germany.
Stäubli Robotics Posted 04/11/2012Five Stäubli RX robots are being used for testing in car satellite navigation equipment at Siemens’ Regensberg plant. Three RX60 models are used for mechatronic final testing on the automated assembly lines, the robot’s precision allowing specific testing of the buttons and rotational transducers.
A fourth is used at an individual workstation at a ‘turntable’ facility, while the fifth robot, a RX130, is responsible for handling and transferring the finished units.
Siemens Automotive produces a wide variety of navigation devices. Before a finished unit leaves the plant, they undergo fully automatic functional testing. The testing is divided into two phases, during preliminary testing; the unit’s internal functions are checked by software developed by Siemens. After this, the navigation devices arrive at final testing.
Each device is transported to an individual testing station using a work piece carrier system. A serial number on a barcode label is used to identify each unit. The complete data available for each unit, includes test results, dates and fault codes, this is stored in the work piece carrier’s memory, from which it can be accessed as necessary by read heads and barcode scanners. This memory data system is based on a transponder with a capacity of 4kB, without an internal power source. Every time it passes over the read and write heads, it recharges with energy. Test data can be entered onto or taken from this readable and write-able transponder. Before the navigation devices arrive at preliminary testing, they are placed on a work piece carrier system and electrically connected to the electronic testing system. At the same time, the computer checks all the component’s internal functions and writes the test results to the work piece carrier’s memory.
After this, a Stäubli RX130 robot moves the units to a different work piece carrier system on the testing line. Faulty devices are automatically weeded out and channeled to a separate rework station, where an electronics technician retrieves the fault data from the fault ticket and corrects repairable faults. Following repairs, the devices are merged back into the testing line and pass through the remainder of the cycle.
The second part of the testing process is the mechatronic test. Three Stäubli RX60 robots simulate the daily use of the navigation equipment by a typical car driver. The robots are equipped with multifunctional rotary end-of-arm tooling that brings the appropriate pin or gripper into position as required and applies it to the equipment. For each device tested, the robots press six specific buttons and operate various rotational transducers. At the same time, software verifies the cable connections between the buttons and the signals from the rotational transducers, as well as the electrical connections of the front panel fitted to the
equipment. Having the robot insert a test CD or CD magazine into the unit and then remove it also tests the functionality of the CD drive and CD changer.
The same procedure is used for telephone cards and cassettes. The duration of the tests is approximately 90 seconds, the timing being determined by the test computer’s operations rather than the speed of the robots. “If the test software determines that there is a mechanical or electronic fault, such as pulses from the rotational transducer not reaching the device, a fault ticket is generated and assigned to the device. These units will again be automatically channeled to a separate rework station,” is how Robert Limmer, Manufacturing Resources and Control Technology project engineer, describes the fault detection process. In addition, a camera checks the front panels for satisfactory labeling and button positions.
There are two test lines: an IDIS (Integrated Driver Information System) test line and an NHU (Navigation Head Unit) test line. On the IDIS line, a camera checks multimedia devices with integrated control panels, using a Vision test system to check the control panels’ LCDs for pixel faults. A navigation test is carried out on both lines.
This involves a gyroscope test, in which the navigation devices are automatically lifted out of their carriers by the robots using a three point gripper, electrically contacted at the rear and rotated in two directions at constant angular velocity by a servo drive. “The signal from a satellite is simulated, and we verify whether the device recognizes the signal. Additionally, the GPS system’s antenna positioning is checked out and a car’s driving motion is simulated,” explains Robert Limmer. The gyroscope is a three-angle sensor in the
navigation equipment that recognizes the vehicle’s attitude and motion and is responsible for fine localization in weak signal areas, such as in a city. “The decisive factors in selecting Stäubli RX robots for these applications were quality, service and geographic proximity to the manufacturer,” explains Karl Buckenleib, Manager of Manufacturing Resources and Control Technology at Siemens. ?