Paper Reading #1: A-Coord Input

A-Coord Input: Coordinating Auxiliary Input Streams for Augmenting Contextual Pen-Based Interactions

This paper was published in conjunction with CHI 2012 on May 5-10 in Austin, Texas. Research was done at the University of Manitoba and the University of Albert (both in Canada) by Khalad Hasan, Xing-Dong Yang, Andrea Bunt, and Pourang Irani. The professors and PhD students specialize in mobile device CHI and work together on a number of different research areas. 

Figure 1. (Hasan et al 805)

Summary

Hasan et al researched the effective use of multiple streams of pen-based input systems. In the past decade, many pen-based input systems have become popular for computer-based design and manipulation. These systems have become fairly advanced and now offer many different ways to manipulate date and input information. Higher-end systems are equipped with pens that allow data input with different amounts of pressure, directional tilt, tilt angle, and rolling of the pen. Many of these input style have been effectively put into practice but very little research has been put into the effectiveness.

Hasan et al conducted two experiments that studied if people were capable of controlling multiple input streams at a time to select a single parameter or a parameter and its value. The first experiment yielded expected results in some ways, but surprising in other. After many trials, it was shown that beginners could easily control multiple input streams to select a single parameter in two dimensions. (Tilt for the rest of the summary means directional tilt). They studied Tilt+Roll, Roll+Pressure, and Tilt+Pressure using Roll+Roll and Pressure+Pressure as controls. It was discovered that although Tilt+Pressure was the most effective in speed, it produced the most errors. The other two (R+P and T+R) took about the same amount of time. Tilt+Roll overall was the most effective due to its low number of errors. Conclusively, the multiple input streams were faster than using the control techniques.

Using the data gathered, they tested these techniques on different types of menus, measuring their effectiveness in speed and error.
 

Related Work

This work is fairly new and uncharted. Many systems use these different techniques to input information but there does not seem to be previous research on manipulating multiple input streams simultaneously. The research Hasan et al uses to base some of their conclusions on are founded in single-channel input styles.

Assessing The Effectiveness of Pen-Based Input Queries, Levin 
Combining bimanual manipulation and pen-based input for 3D modeling, Lopes

Evaluation

All of their evaluations were done objectively and quantitatively. The testing sessions were timed by the computer and tests were carefully created to gather the most accurate information possible. They did however make a subjective claim by balancing the information regarding errors and time.

Discussion

Overall I enjoyed reading about their research and I thought it was very well done.  For much of the article I thought they had not considered the fact that these pens are already used in a 2D space and adding two more inputs creates three inputs streams a person has to control.  In their discussion they revealed that since most of the research was done to make menus easily accessible, they did not think it would be necessary to move the pen while using the other two input streams.  Much of the menus we encounter on our screens look cluttered and are hard to navigate if there are more than 10 options, but this method could allow up to 64 choose-able options on a single menu.  I think this research could one day open up possibilities of interacting with a computer in totally new ways.  Current software is not built for such a new type of input and would have to be reconfigured to support such useful technology.