Optimisation of medical patient couches with miniature draw-wire sensors

With the SXM30 miniature draw-wire sensor, WayCon Positionsmesstechnik GmbH offers the ideal sensor for extremely confined spaces.

Draw-wire sensors are precise measuring systems that determine the distance or position by means of a measuring wire attached to the measured object. Due to the direct contact with the measured object, the measurement is not affected by dust or ambient light. This offers a decisive advantage over non-contact sensors such as laser sensors. The use of deflection rollers also makes it possible to measure in hard-to-reach places. Measuring around corners is also no problem.

The miniature draw-wire sensors of the SXM30 series, whose housing diameter of 31 mm is the same as that of a bottle cap, achieve measuring lengths of up to 750 mm. With its ultra-light, fibreglass-reinforced plastic housing, the sensor weighs just 50 g. The compact sensor achieves an accuracy of up to ±0.1% of the measuring range. The draw-wire sensor has a hybrid conductive plastic potentiometer with 1 kΩ resistance (optionally 5 kΩ or 10 kΩ), making it easy to connect to displays, e.g. from the WAY-AX series. Alternatively, a signal conditioner from the PMX-24 series can be used to convert the output into an analog current or voltage signal. A cost-effective economy version is also available for the 500 mm and 750 mm measuring ranges.

Their ultra-compact housing makes draw-wire sensors from the SXM30 series ideal wherever there is no room for other sensors. One tried and tested area of application is medical technology, where miniature draw-wire sensors are used to measure the position of patient couches, among other things. Thanks to the use of precise sensors, the patient couches can be positioned with millimeter precision during computed tomography, thus enabling optimal image reconstruction. Draw-wire sensors are also used on modern operating tables with individually adjustable elements to enable the surgeon to move the patient into the perfect position at the touch of a button. Draw-wire sensors also find similar use in dental chairs.

However, these versatile sensors are not limited to medical technology. Draw-wire sensors also help with precise measurements of distance, position and length in other industries, such as model making and vehicle construction.