Systems
The diversity of skills at ASULAB is an asset in the development of complete systems using the capabilities of new components or new materials. Systems are designed in interdisciplinary projects involving many of our collaborators. Besides the projects mentioned under "Watches" and "Components", some of our recent developments in various fields are cited here below.
Glucose measurement system
The blood-sugar measurement system developed by ASULAB consists of an easily portable measuring instrument and sensors in the form of strips. The blood is applied to the measurement field of the sensor and reacts with the sensor chemicals. This chemical reaction generates an electric current which is measured by the instrument, acting as an ammeter.
The system was developed for periodical monitoring of the blood-sugar level in diabetic patients and is distinguished both by its small size and elegant shape, as well as by its ease of use. The instrument measures the glucose content in only 15 seconds, is operated by a single button, and has a storage capacity of 500 measured values, which can be transferred to a computer and evaluated there, if required. Owing to the use of our very low-power watch processors, the instrument has a very low current consumption and achieves a battery life of over five years.
Glucose meter
Power module
For electric vehicles, ASULAB has developed a compact IGBT (Insulated Gate Bipolar Transistor) module with integral liquid cooling. The electrical and thermal contacts with the IGBT semiconductor are mechanical pressure contacts. In this way, good reproducibility of the thermal resistances from IGBT to cooling liquid is achieved as well as a lower power loss through replacement of the emitter bond wires by a solid pressure contact.
The figure shows a computer-synthesised image of a complete module.
Power Modul
Generator in the shoe
From the automatic mechanical watch we know that the energy provided by ordinary human body movement is sufficient to supply small systems. The automatic winding mechanism of a watch supplies a power of about 1 µW, as an average over a day.
For systems with a significantly higher power consumption, the energy provided when walking is suitable, and ASULAB has developed a generator in the heel of a normal shoe which produces about 0.3 Joule per step. The generator consists of a metal frame, plus a compression spring. The weight of the body compresses the spring which drives the generator via a rack and pinion arrangement, when it is released.
The design is protected against overload and relatively compact, as can be seen from the schematic drawing shown.
Generator in the shoe
Rain detector for motor vehicles
The ASULAB rain detector has been developed for the automatic operation of motor-vehicle windscreen wipers. The detector allows fully-automatic control of the windscreen wipers in intermittent mode, at lower and higher speed, and can also be used on rear screens. The detector operates on the ultrasound principle and consists of a piezo-electric ultrasound transducer which is mounted on the inside of the windscreen (for laminated screens, on the inside of the outer layer of glass).
By means of a short high-frequency pulse, the transducer excites the glass screen locally to resonance. The ultrasound wave thus generated in the glass is reflected repeatedly back and forth by the two glass surfaces. If there is a water drop (or several drops) or a film of water on the outer surface of the glass, the ultrasound wave is more markedly damped and decays rapidly. The decaying signal is measured by means of microprocessor electronic circuitry, and the wiper motor is controlled accordingly.
The ultrasound principle is basically insensitive to any form of interference by light, and the detector can also be mounted beneath decorative films or tinted glass, so that it is invisible.
In addition to applications in the automobile industry, the detector can also be used in building technology, for automatic irrigation systems and wherever reliable and low-power detection of spray or rain is needed.
