For one thing, lighter is better is the use of touch especially in this device where one isn't supposed to hold the camera still, but it is intended that the camera be moves and a person feels letters scrolling underneath the finger identifying character combinations and patterns. Also, what you are describing may be a tactile illusion. (grin) Pressing more firmly degrades the efficacy of the finger's receptors, so it might seem that one is feeling more on the sides than with the skin of the finger touching the bottom of the trough of receptors. There are an intensity control and threshold control the former providing the modification of the intensity of the vibration of the reeds in the array. A tool used outside the context in which it was intended will often give exotic results. But a tool intended for research should be tuned up if only to make sure it is indeed functioning within it's design parameters (calibration). It may be beneficial to check out parameters of the device in maintenance, and other manuals for data beyond slippery anecdotal perceptions of what the device is or is not supposed to act like, as those of us using older or less frequently serviced devices may have come to accept and even cherish the idiosyncratic behaviors of our own beloved instrument for reading independence. (smile) Finally, no two arrays felt exactly alike because of the variations in reeds, and effects of the use of human assembly and non-instrument based QA procedures among other things. W. Nick Dotson ----- Original Message ----- From: "Richard Vickery" <Richard.Vickery@xxxxxxxxxxx> To: <optacon-l@xxxxxxxxxxxxx> Sent: Sunday, November 29, 2009 9:58 PM Subject: [optacon-l] Request for some advice > Hello everyone, > > I am a University-based neuroscientist at UNSW in Australia. We are using > an > Optacon R1-B as a research tool to investigate tactile function. This is > primarily basic research, but may in the longer term have application in > the > development of better haptic feedback devices for remote sensing and > assisting > the disabled. > > Our Optacon is very sensitive to the contact force between the finger and > the > device. If you hold your finger down on it too firmly, the pins barely > move and > are difficult to detect. Also the sensation produced by each column seems > different with the side ones being least effective. I was hoping that you > expert > Optacon users might be able to tell me if all Optacons behave this way, or > whether our one is in need of a major overhaul. > > > Thanks in advance for your help, > > Best wishes > Richard Vickery > > > -- > Dr Richard Vickery > School of Medical Sciences, UNSW, Australia, 2052 > ph. 61 2 93851676, fax 61 2 93851059 > > > > > > > > to view the list archives, go to: > > www.freelists.org/archives/optacon-l > > To unsubscribe at any time, just send a message to: > > optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the > quotes) in the message subject. > > Tell your friends about the list. They can subscribe by sending a message > to: > > optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the > quotes) in the message subject. > to view the list archives, go to: www.freelists.org/archives/optacon-l To unsubscribe at any time, just send a message to: optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the quotes) in the message subject. Tell your friends about the list. They can subscribe by sending a message to: optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the quotes) in the message subject.