Accuracy, repeatability, and safety are critical aspects in the manufacture of many devices, especially those that have stringent quality requirements such as medical, industrial, or transportation systems. These are also key features that distinguish UR cobots—and make them ideal for testing these products for quality assurance.
The ability to automate routine testing operations with a high degree of efficiency provides multiple advantages. In the production phase, automation can significantly shorten cycle times and in the quality-control stage, the standardization of test batteries ensures uniform and reliable results.
This was the case for the BioRobotics Institute of the Sant'Anna School of Advanced Studies in Pisa, Italy where a research team developed a robotics application that automates the functional tests on ultrasound probes. The probes are produced by ESAOTE, one of the world's leading manufacturers of biomedical equipment, in particular in the field of ultrasound, dedicated magnetic resonance and software for the management of the diagnostic process.
The UR5 model was chosen for the test automation. With a 5 kg load capacity and 850 mm reach in a robot arm that weighs less than 19 kg, the UR5 is flexible and versatile enough for many quality control and pick-and-place operations.
AUTOMATION IMPROVES TEST PRECISION AND REPEATABILITY
Before the integration of the application developed by the Pisa team, test batteries on the probes were manually performed by specialized technicians. The tests verify the degree of precision expressed by the probe by analyzing the signal emitted in a container full of water. Water is typically used in this kind of measurement since its acoustic properties (such as ultrasound velocity) match those of body tissues. For these tests, the accurate alignment of the probe is crucial. Comparing the data from three tests with manual alignment against those of three tests with robotic alignment left no doubt: the collaborative robots guarantee more precise and repeatable data.
The developers are able to record the starting position of the robotic arm through three spatial coordinates (x, y, z) in space, which they can set during the programming phase. This speeds the test setup and makes the process more reliable. In fact, this ability eliminates variables that inevitably came into play with manual positioning of the probe.