Not a member yet? Register for full benefits!

Robot Researcher For Glass-Glues

Computerised researchers are becoming an increasing trend it would seem. We've seen an increase in recent years of drug-testing robots and automated researchers. Glass researchers are apparently the latest field to be hit with the automation bug.

The reason? The rapidly increasing amount of electronics in a modern car. As cars are expected to do more and more, so the space between the driver and the engine block is rapidly filling up with electronics of all kinds, from 'essential' services such as remote engine control, voice activation, and smart parking, to luxury items like USB ports, and video screens.

Everything that is added takes up more space between the mechanicals and the engine itself. As the electronics creep ever closer to the engine so they must deal with an increasing need for heat dissipation lest the heat of the engine melt the sensitive electronics. This is where the glass comes in. It is a type of glass solder used as a glue binding the electronics together, and serving as a heat sink between the hot metals and the electronics themselves.

Worse, when hybrid cars are added into the mix, with both gasoline and fuel cell power supplies – or even just fuel cells, the components and their glue must be expected to withstand temperatures up to 900 degrees C.

This solder is as is perhaps now abundantly clear, not just ordinary glass. Instead it is a complex mix of different elements, designed with certain characteristics in mind. This glass can consist of 50 to 60 different elements. Experts are continually tasked with creating new blends of glass with certain specific characteristics out of these elements, as more often than not, a new application requires new support materials.

In the case of the electronics in a car, the components that are edging ever closert to the engine must be able to resist both heat and corrosive gasses.

In order to develop glass with new characteristics, experts select about ten compounds from potential elements, mix them and then heat the powder. They heat it in a furnace until it is soft, then they pour it into a mould and let it cool slowly and in a controlled fashion, down to room temperature. During that process small samples from the viscous glass are taken to test it: how viscous is it? How well does it wet metals? How does it crystallize out? To produce the glass samples by hand and to test them requires a lot of time: one employee needs approximately two weeks to process 16 samples.

Clearly then, there is a niche for an automated researcher to fit into – one that never eats, never sleeps, never wavers in concentration or focus. Enter the Fraunhofer Institute. Specifically, the Fraunhofer Institute for Silicate Research ISC in Würzburg, Germany. Doctor Martin Kilo, manager of the expert group for glass and high-temperature materials, along with his team have developed an automated researcher that carries out all these steps automatically.

"It needs only 24 hours to process 16 samples", Dr. Kilo stated. "For this reason we are able to develop glass elements more cost-effectively than previously, by up to 50 percent."

The core piece of the unit is a robot: it puts a mixing cup on a scale and moves it under 14 storage vessels, from which a certain amount of powder is filled into the cup. Then the robot mixes the individual ingredients by closing the cup and shaking it, just like a bartender does with a cocktail shaker. The robot arm then grabs a crucible, puts it onto the scale, fills it with a certain amount of the mixed powder and puts the crucible into one of the five furnaces available in total. The robot repeats this steps several times, since gases build up when the powder is heated and foam could form otherwise.

In addition, the powder shrinks during the melting process. Finally the furnace heats the fully filled crucible to a higher temperature, causing the gas bubbles in the glass to rise to the surface. Once the glass is viscous, the robot arm removes the crucible, pours the glass into a new mould and places it in a stress-relieving furnace. Here, the glass cools slowly and in a controlled manner, from 600 to 800 degrees Celsius down to room temperature.

Measurement is carried out in tandem with another part of the same system; the analysis unit works via thermo-optical measurement, and in stereoscopy so as to garner a full 3D view, analyses the shade the sample projects in a backlight test system, via machine vision. A recording is also made, for the benefit of human researchers if necessary.

The changes in the contour make it possible to determine characteristics such as sample volume, hemisphere point and wetting angle. This test unit measures how viscous the melt is, and if and how it crystallizes and wets metals. In short, every aspect of the research process.

The only thing it cannot currently do, is determine for itself which recipe to try next; whilst it is an expert system, it is not one that has so far been designed to make it's own decisions or learn from it's own research. When we have automated systems capable of all these attributes in a single system, only then will the careers of human researchers be in doubt.


Robot speeds up glass development

Staff Comments


Untitled Document .