(Actually, that is the url of a pdf describing a button array. -Ed.)

It apparently mounts on a PCB. (“Interesting. Tell me more.” -Ed.)

The buttons are small. 4 or 5 mm. and adhesive. With a life expectancy of 500,000 presses (that is, more than 1200 presses per button per day for a year). They can be designed and produced according to user specifications (external dimensions or key lay out).

Here is a version which comes in strips rather than in a 2D array:

The operating force is 1.6 N. The height is 0.47 mm. The strip version is available in units of 6000 pieces. including supplies etc. Makers of force-sensing resistors, including variable resistance touch sensors, available as .2 inch circle, .5 inch circle, 1.5 inch square, and 24 inch trimmable strip, with prices about $5/ea. They may send samples. (See also ElectronicSuppliers)

Several packaged solutions (including drivers) from a San Jose based company called synaptics.

Online intro to piezoelectric pressure sensors:

as advertised, and resulting from research dollars of the canadian space agency, a pressure sensitive fabric based package based on embedded fiber-optic network. Recently also productized in Midiman's SurfaceOne? Midi controller. We just received one at work, so I will try it out.

From one manufacturer:

Security mats: somewhere I have information on this from the Max/MSP mailing list.

The university of Berkeley has developed what the call 'motes', or “an Open Experimental software/hardware Platform for Network Embedded Systems Technology research that will accelerate the development of algorithms, services, and their composition into challenging applications dramatically. Small, networked sensor/effector nodes are developed to ground algorithmic work in the reality of working with numerous, highly constrained devices.”

TinyOS is a component based os for embeded networked devices which controls the mote's hardware

resourses list

crossbow. sensor equipment manufacturers →

General Description

The ADXL202 is a low-cost, low-power, complete 2-axis accelerometer with a measurement range of ±2 g. The ADXL202 can measure both dynamic acceleration (e.g., vibration) and static acceleration (e.g., gravity).

The outputs are Duty Cycle Modulated (DCM) signals whose duty cycles (ratio of pulsewidth to period) are proportional to the acceleration in each of the 2 sensitive axes. These outputs may be measured directly with a microprocessor counter, requiring no A/D converter or glue logic. The DCM period is adjustable from 0.5 ms to 10 ms via a single resistor (RSET). If an analog output is desired, an analog output proportional to acceleration is available from the XFILT and YFILT pins, or may be reconstructed by filtering the duty cycle outputs.

The bandwidth of the ADXL202 may be set from 0.01 Hz to 6 kHz via capacitors CX and CY. The typical noise floor is 500µg÷Hz allowing signals below 5mg to be resolved for bandwidths below 60Hz.

The ADXL202 is available in a hermetic 14-lead Surface Mount Cerpak, specified over the 0∞C to +70∞C commercial or -40∞C to +85∞C industrial temperature range.

The ADXL202E is an improved, smaller version of the ADXL202, low-cost, +/-2 g, dual-axis accelerometer. The ADXL202E features improved sensitivity and zero g bias limits, lower noise, wider 3dB frequency response, and lower price than the ADXL202. It is offered in a 5mm x 5mm x 2mm, 8-pin LCC package.

ADXL210(e) is a 10g range verison of the same concept.

  • sensor_technology.txt
  • Last modified: 2007-06-26 10:25
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