pliance: Pressure mapping for office chair
Nowadays, an increasing amount of time is spent seated, especially in home-office or office environments, where sitting comfort and support are increasingly important due to the prevalence of musculoskeletal disorders.
The pliance® system offers the state-of-the-art technology for pressure distribution measurement on the seat pan and back rest. The system consists of a flexible and elastic sensor measuring mat, a multi-channel analyser, a calibration device, and a software package for Windows PC.
The novel pliance® measuring system is today a standard tool in the ergonomic product industry.
pliance® sensor mat
As in all physical measuring systems the most important part is the sensor technology. As all novel systems the pliance® system is also based on calibrated, accurate, and reliable capacitive sensors. The individual sensor elements are elastic and arranged in a matrix which conforms well to three-dimensional shapes.
The pressure transducing elements contain high-tech elastomers manufactured by novel. Restoring force, range of force, threshold, hysteresis, temperature effect, frequency response, and other characteristics such as elasticity are determined during the manufacturing process. This makes it possible to adapt the sensor characteristic to different measuring needs.
The pliance® sensor mat can be used either for the seat or the back. Nevertheless, it is also possible to monitor the seat and the back simultaneously with two or more sensor mats. The elastic measuring mats are available in various sizes, sensor configurations, and pressure ranges.
trublu® calibration device
With the aid of the trublu® calibration device, all pliance® sensors are individually and simultaneously calibrated with homogeneous air pressure. Calibration guarantees accurate and reproducible data collection.
The calibration device can be used at any time to verify the quality of the measuring results. It uses homogeneous air pressure on all sensors through increasing steps of pressure. Thus an individual calibration curve for each sensor can be calculated. The software operates in a Windows environment and contains many useful methods of data collection and scientific analysis of dynamic pressure. It also allows continuous memory of data.
The pliance® analysers vary from small portable 16 x16 channel units to larger 64 x 32 channel units (collection up to 2,048 sensors possible) with a wide range of options, such as master-slave synchronisation of several systems, dynamic amplification control, and synchronisation of video systems.
The pliance® sensor mat is connected to the novel pliance® analyser. The pliance® analyser technology allows individual calibration curves for each sensor and individual dynamic amplification control and crosstalk suppression, resulting in very accurate and reproducible pressure values. The pliance® analyser communicates with the PC via fibre optic/USB interface, via Bluetooth® or a removable SD card.
Features of the pliance® system
• Conforms perfectly to the seat and back
• Each sensor is individually calibrated
• Can be synchronised with video and other systems
• 2D, 3D display, or isobar display
• Allows manifold analysis of measurement data
Various pliance® sensors for other applications are available, e.g. for measurements of head-rest, arm rests, and castors.
The pliance® software operates as a Windows application and allows easy data collection of pressure distribution. Data can continuously be stored in online mode and handled with a configurable SQL database. Different levels of pliance® measuring software are available.
Using novel scientific software the expert is also able to design the parameter configuration to specific needs and exchange data with colleagues via HTML protocol. Individual reports can be created by the user to allow quick and easy data analysis.
Seat pan and backrest pressure distribution while sitting in office chairs (RolandZemp, William R.Taylor, Silvio Lorenzetti)