Give your robot the sense of touch! Read up to 32 FSRs with this touch sensor board. Daisy-chain four (4) boards and read up to 128 FSRs through one parallel port.
Touch Sensor Board and supporting equipment. Priced at $ 595 (including S&H inside the US, add $30 for overseas shipping).
This board can read any analog signal in the 0 - 5v range. $450 without the FSRs.
Board & FSRs Board & cables
FSR Theory and History
A Force sensing resistor (FSR) is somewhat similar to a strain gauge with two major differences. First, since most strain gauges are made of ceramic material, they will break if deflected very much. An FSR is made from a polymer so it can withstand greater deflection. Second, the response of most strain gauges is linear so that its sensitivity is limited. However, the response of an FSR is logarithmic so that its response covers a wider range with more accuracy. FRSs are an offshoot of the music industry. When musical keyboards first appeared, the keyboards had no sensitivity so that when you hit a key, you always got the same response. Musicians wanted to get a variable response which depended on how hard they hit the keys. Hence the FSR was developed to satisfy that demand.
The size of the FSR shown here is about 1/4" (6mm) wide and about 1 5/8" (40 mm) long. It would be nice if they were smaller. The manufacturer has told me that I need to buy at least 10,000 a month for 6 months in order for them to make a customized model for us.
From: Mr. Morten Strandberg in Sweden, 5/31/01
As a matter of fact I tried it (his touch sensor board) out yesterday and I was REALLY IMPRESSED with the sensor's performance! No hysteresis whatsoever when unloaded, little drift during static load, logarithmic response. IT WAS REALLY GREAT!
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