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TECH NEWS
Germany: Smart screws keep infrastructure safe Screw connections on critical infrastructures are exposed to major stresses and must be checked regularly. Researchers have developed a technology - The Smart Screw Connection - that allows the stability of the screw connections to be checked at any time by remote monitoring. It is a fully integrated, self-powered IoT device for determining the preload force. The data is transmitted wirelessly and is designed as a flexible, retrofittable system for DIN screws of various sizes. It comes with a screw fitted with a washer that is equipped with a piezoresistive DiaForce® thin film. When the screw is tightened, the pressure-sensitive sensors register the preload force at three points. Any change in the preload force changes the electrical resistance. When a screw comes loose, the resulting change in resistance is reported to a radio module located on the screw head. The radio module, in turn, sends the data to a base station. It can be adapted for a wide variety of applications. Fraunhofer
– envisioning a future where a robot or stretchy electronic devices could be 3D printed via the press of a button. The researchers first designed a series of computer simulations that probed the physics of printing different kinds of materials next to each other. One of the big problems was how to keep droplets of solid materials from mixing into the liquid materials. The team established a set of rules to help them A network of capillaries 3D-printed do that. The surface using a newly developed technique. tension of a liquid can be used to support solid material, but it is helpful to pick a liquid material that is more dense than the solid material. Next, the researchers experimented with a real 3D printer in the lab. They loaded the printer with a curable polymer, or plastic (the solid), and with a standard cleaning solution (the liquid). Their creations were impressive: The group was able to 3D-print twisting loops of liquid and a complex network of channels. University of Colorado at Boulder
USA: Waterless dust removal for solar panels
The Smart Screw Connection is a fully integrated, self-powered IoT device for determining the preload force.
UK: Rail sensor goes ultrasonic to grease the wheels Engineers are working on an ultrasonic sensor for the rail industry that can detect sections of track where vital lubrication has been worn away. The sensors will be embedded in the wheels of trains and will allow track conditions to be almost continuously monitored. In curved track, a special type of grease is applied between the wheel and rail to reduce wear but also the risk of derailment, whereby in some circumstances the wheel can climb up and over the railhead. This new measurement technology will provide an automated vehicle-mounted system that will communicate the presence of lubrication, and critically, locations where it is absent, thereby reducing maintenance costs and improving railway safety. Embedding ultrasonic sensors into the wheel provides the opportunity for continuous monitoring of lubrication effectiveness and allows preventative measures to be applied before problems arise. The Engineer
US: How to print a robot from scratch: Combining liquids, solids A team has established a strategy for using currently available printers to create materials that meld solid and liquid components
AMT JUN 2022
The accumulation of dust on solar panels or mirrors is a significant issue — it can reduce the output of photovoltaic panels by as much as 30% in one month. But cleaning solar panels is estimated to use about 10 billion gallons of water pa. Attempts at waterless cleaning are labour-intensive and tend to cause irreversible scratching of the surfaces. Now, a team has devised a way of automatically cleaning solar mirrors in a waterless, no-contact system that could significantly reduce the dust problem. The new system uses electrostatic repulsion to cause dust particles to detach and virtually leap off the panel’s surface, without the need for water or brushes. To activate the system, a simple electrode passes just above the solar panel’s surface, imparting an electrical charge to the dust particles, which are then repelled by a charge applied to the panel itself. The system can be operated automatically using a simple electric motor and guide rails along the side of the panel. MIT
USA: Heat engine with no moving parts as efficient as a steam turbine Engineers have designed a heat engine with no moving parts. Their new demonstrations show that it converts heat to electricity with over 40% efficiency — a performance better than that of traditional steam turbines. The heat engine is a thermophotovoltaic (TPV) cell, that passively captures high-energy photons from a white-hot heat source and converts them into electricity. The researchers plan to incorporate the TPV cell into a grid-scale thermal battery. The system would absorb excess energy from renewable sources such as the sun and store that energy in heavily insulated banks of hot graphite. When the energy is needed, TPV cells would convert the heat into electricity, and dispatch the energy to a power grid MIT
