UIST2009: TapSongs: Tapping Rythm-Based Passwords On A Single Binary Sensor

Author: Jacob O. Wobbrock

Summary:
    The author starts out by pointing out that many devices are coming out that have just one binary sensory input.  To access a device like this a user could have to tap in their password to some preselected rhythm.  Of course a user wouldn't be able to enter at the exact same each attempt so some room for error would have to be allowed.  When the authors performed a study users had to enter in the rhythmic password 12 times to make sure their timing was consistent.  When trying to log in after training users messed up just over 80% of the time.  The authors did not say how strong these passwords would be.

Discussion:
    This paper is interesting because more and more electronic devices are coming out that could implement this idea.  The first concern that comes to my mind is how well can people remember these types of passwords over a long time.  What if the user hasn't logged in for a week, a month, or even a year.  Another concern is that the author failed to test security issues with these types of passwords.  I would try and test both of these things if possible because they could cause major problems if someone were to implement this idea.

UIST2009: Disappearing Mobile Devices

Summary:
     This paper discusses making mobile devices small enough to be unseen or integrated into the human skin.  The author starts out by noting that mobile devices still need to be large enough for user interaction. To minimize the size of a mobile device it is possible a small projector for visual display could be inserted into the skin.  Another option would be to insert the mobile device into a watch.
    Any sort of miniature mobile device must contain a few things.  For one it has to output to the user either in the form of an LED, projector, or audio.  It also needs to accept input which can come from touch, pressure, motion, or sound.  The author then talks about using several types of motions to get user input from a sort of watch device. He also talked about errors that occurred when testing the watch.


Discussion:
     I would like to start out by saying people probably won't have devices implanted into their skin until they are extremely small.  Not only would it be awkward but we don't know if this would be safe.  Personally I would never have an electronic implanted into my body unless absolutely necessary.  I think the idea of a watch as a mobile device sounds much more practical although I haven't seen any projection technology that would satisfy me as a permanent user interface for my phone.  However, I don't think I will be replacing my LCD touchscreen mobile device any time soon.

UIST2009: A Practical Pressure Sensitive Keyboard

Summary
     This paper discussed a possible method for creating a pressure sensitive keyboard.  This is not talking about a touchscreen keyboard as I first thought.  This means when the key is pressed there is a pressure sensor underneath it to detect how hard the key was pressed.  These type of keyboards already exist but they use springs rather than a true pressure sensor.  The problem with the spring pressure sensors is that they can be rather noisy and they consume more power.  The author also mentions that their keyboard could be mass produced.

A traditional keyboard on the left, a pressure sensing on the right, the main difference is the bottom contacts which are used for detecting pressure on the left

Discussion
      This paper is significant because it discusses a way to build a pressure sensing keyboard that can be mass produced.  There are several advantages for this new keyboard.  For one it requires less power than other types of keyboards.  Older keyboards can't handle when more than two keys are pressed on a row at once.  The design of this keyboard allows this to occur.  Some uses for a pressure sensing keyboard include gaming where different amounts of pressure to the key could perform different actions.  The author also discusses "emotional instant messaging" where depending on how hard you hit the keys the letters show up larger or smaller.
     One fault of this article that I found was they really haven't tested the demand for a keyboard like this.  They claim it could be used for several different applications but the only one I found convincing was the gaming.  Unless someone comes up with a better way of designing a pressure sensing keyboard I believe it will be put to mass production in the future.

UIST2009: ARC-Pad: Absolute+Relative Cursor Positioning for Large Displays with a Mobile Touchscreen

Authors: David C. McCallum & Pourang Irani from University of Manitoba
Summary
     This paper covers ARC-Pad which is short for Absolute+Relative Cursor pad.  ARC-Pad is a method for controlling the cursor of a large screen display from a mobile phone with a touchscreen.  The authors claim that ARC-PAD has several benefits when compared to other techniques.
    ARC-Pad works by combining absolute and relative cursor positioning methods.  Absolute cursor positioning is when the cursor on the big screen corresponds to the exact location the user touches on the touch screen.  Relative cursor positioning is when the cursor moves a certain distance depending on how far a user moves their finger on the touchscreen.  In previous methods the user had to explicitly switch between relative and absolute modes.  ARC-Pad achieves this by going into absolute mode if the user taps the screen lightly and goes into relative mode if the user drags their finger on the touchscreen.  This saves the user time by not having to explicitly switch between modes.

     The authors also talked about clutching.  Clutching is the amount of time the user drags his finger on the touchscreen.  One thing ARC-Pad does to reduce clutch time is it makes use of Control-Display gain.  Control-Display gain is when finger movements on the touchscreen are amplified resulting in large movements on the big screen.  This will decrease clutch time but it will also decrease accuracy when the Control-Display gain is too high.  Another technique used to reduce clutch time is cursor acceleration.  When the user drags their finger across the touchscreen faster the cursor will travel further on the big screen.
     All in all the ARC-Pad has two main benefits.  One, it reduces cognitive load by not requiring the user to switch between relative and absolute cursor positioning.  Secondly, it reduces occlusion of the screen by not taking up any of the display like other techniques do(radar view). 

Discussion
     This paper was significant because it was a practical solution to improving cursor positioning on displays from mobile touchscreens.  The authors found that ACR-Pad reduced clutch time and the amount of time it took to move the cursor across the screen.  The differences were much more noticeable the longer the distance the user had to move.  However, the authors only mention performing one experiment with ACR-Pad leading me to believe their could still be some faults in their plan.  In the experiment they use a HTC TouchDiamond mobile phone with a 640x480 and a 52" monitor with a 1360x768 display.  Since the display ratios are different, the speed at which the phone could move the cursor had to be adjusted.  This raised a few questions in my mind.
    First, even though the experiment went smoothly with their display ratios, what if the display ratios were much different?  If there was say a business presentation on a large screen with very different dimensions than the phone, would this technique work as smoothly as the others?  I would think so, but I'm sure once the difference in ratios between the screens was so extreme this would eventually present a problem.
    Second, how does the HTC TouchDiamond touchscreen compare to other touchscreens today.  Is it more or less accurate than an iPhone?  If it is a lot more accurate than other phones to the touch of a finger, then absolute cursor positioning could become a problem with other phones.  Also, what percent of the time does the phone believe a quick touch is a drag and vice versa?  Having experience with an iPhone, I know touchscreens sometimes are more difficult to work than intended.
    Future uses of this technology could be widespread.  First, they need to try it with many different devices and monitors.  The authors also mention in the paper this could eventually be used on laptops to control the cursor when it is hooked up to a monitor.  Controlling the mouse on a large monitor from a laptop touch pad can sometimes be very frustrating.  Another future use they mention is they could implement dragging and dropping icons much quicker.  The user could start dragging the icon with their finger then tap the screen once to go into absolute cursor positioning and move the icon anywhere on the screen with the click of a finger.  The would greatly reduce clutch time when dragging icons.