Performance, Characteristics, and Error Rates of Cursor Control Devices for Aircraft Cockpit Interaction

This document is the Accepted Manuscript version of the following article: Peter R. Thomas, 'Performance, Characteristics, and Error Rates of Cursor Control Devices for Aircraft Cockpit Interaction', International Journal of Human-Computer Studies, Vol. 109: 41-53, available online 31 August 2017. Under embargo. Embargo end date: 31 August 2018. Published by Elsevier. © 2017 Elsevier Ltd. All rights reserved.This paper provides a comparative performance analysis of a hands-on-throttle-and-stick (HOTAS) cursor control device (CCD) with other suitable CCDs for an aircraft cockpit: an isotonic thumbstick, a trackpad, a trackball, and touchscreen input. The performance and characteristics of these five CCDs were investigated in terms of throughput, movement accuracy, and error rate using the ISO 9241-9 standard task. Results show statistically significant differences (p < 0.001) between three groupings of the devices, with the HOTAS having the lowest throughput (0.7 bits/s) and the touchscreen the highest (3.7 bits/s). Errors for all devices were shown to increase with decreasing target size (p < 0.001) and, to a lesser effect, increasing target distance (p < 0.01). The trackpad was found to be the most accurate of the five devices, being significantly better than the HOTAS fingerstick and touchscreen (p < 0.05) with the touchscreen performing poorly on selecting smaller targets (p < 0.05). These results would be useful to cockpit human-machine interface designers and provides evidence of the need to move away from, or significantly augment the capabilities of, this type of HOTAS CCD in order to improve pilot task throughput in increasingly data-rich cockpits.Peer reviewedFinal Accepted Versio

Enabling self-directed computer use for individuals with cerebral palsy: a systematic review of available assistive devices and technologies

Aim  The purpose of this study was to systematically review published evidence on the development, use, and effectiveness of devices and technologies that enable or enhance self-directed computer access by individuals with cerebral palsy (CP). Methods  Nine electronic databases were searched using keywords ‘computer’, ‘software’, ‘spastic’, ‘athetoid’, and ‘cerebral palsy’; the reference lists of articles thus identified were also searched. Thirty articles were selected for review, with 23 reports of development and usability testing of devices and seven evaluations of algorithms to increase computer recognition of input and cursor movements. Results  Twenty-four studies had fewer than 10 participants with CP, with a wide age range of 5 to 77 years. Computer task performance was usually tested, but only three groups sought participant feedback on ease and comfort of use. International standards exist to evaluate effectiveness of non-keyboard devices, but only one group undertook this testing. None of the study designs were higher than American Academy for Cerebral Palsy and Developmental Medicine level IV. Interpretation  Access solutions for individuals with CP are in the early stages of development. Future work should include assessment of end-user comfort, effort, and performance as well as design features. Engaging users and therapists when designing and evaluating technologies to enhance computer access may increase acceptance and improve performance

An Arm-Mounted Accelerometer and Gyro-Based 3D Control System

This thesis examines the performance of a wearable accelerometer/gyroscope-based system for capturing arm motions in 3D. Two experiments conforming to ISO 9241-9 specifications for non-keyboard input devices were performed. The first, modeled after the Fitts' law paradigm described in ISO 9241-9, utilized the wearable system to control a telemanipulator compared with joystick control and the user's arm. The throughputs were 5.54 bits/s, 0.74 bits/s and 0.80 bits/s, respectively. The second experiment utilized the wearable system to control a cursor in a 3D fish-tank virtual reality setup. The participants performed a 3D Fitts' law task with three selection methods: button clicks, dwell, and a twist gesture. Error rates were 6.82 %, 0.00% and 3.59 % respectively. Throughput ranged from 0.8 to 1.0 bits/s. The thesis includes detailed analyses on lag and other issues that present user interface challenges for systems that employ human-mounted sensor inputs to control a telemanipulator apparatus

Investigation of Unintentional Movement in People with Cerebral Palsy to Improve Computer Target Aquisition

People with Cerebral Palsy (CP) have difficulty using computer pointing devices due to unintentional movement in their upper extremities. Fifty percent of people with CP have impaired arm-hand function which limits their ability to interface with pointing devices and effectively control cursor movement on the computer screen. This thesis involves two studies which utilize an Isometric Joystick in order to access the computer and complete target acquisition tasks. The first study titled "Quantification of Cursor Movement of People with Athetoid and Spastic Cerebral Palsy to Improve Target Acquisition," aims to guide real-time digital filter development for people with athetoid and spastic CP for target acquisition tasks. By investigating the cursor movement measures throughout the target acquisition trajectory we gained a better insight as to when and how to compensate for unintentional movement in people with CP. Results showed that both people with athetoid CP and spastic CP have more difficulty hovering over the target than they did moving to the target, indicating that filter development should focus on the hovering portion of the target acquisition task in order to improve target acquisition time. The second study titled "Customized Control for People with Athetosis and Dystonia to Improve Computer Access," aims to develop a method to prescribe appropriate switch/scanning control for people with athetosis and dystonia as well as to determine if customized switch/scanning control is more effective in completing icon selection tasks than the proportional isometric control. Results of this study suggest that switch/scanning control could be useful in moving on the most direct path to the target as shown by a significantly smaller percent distance error for customized control as compared to proportional isometric control (F(1,6) = 361.2, p < 0.01)

Assessment of Fitts' Law for Quantifying Combined Rotational and Translational Movements

Objective: To develop a model for human performance in combined translational and rotational movements based on Fitts' law. Background: Fitts' law has been successfully applied to translational movements in the past, providing generalization beyond a specific task as well as performance predictions. For movements involving both translations and rotations, no equivalent theory exists, making comparisons of input devices for these movements more ambiguous. Method: The study consisted of three experiments. In the first two, participants performed either pure translational or pure rotational movements of 1 degree of freedom. The third experiment involved the same movements combined. Results: On average, the performance times for combined movements were equal to the sum of the times for equivalent separate rotational and translational movements. A simple Fitts' law equivalent for combined movements with a similar slope as the separate components was proposed. In addition, a significant degree of coordination of the combined movements was found. This had a strong bias toward a parallel execution in 12 out of 13 participants. Conclusion: Combined movements with rotations and translations of 1 degree of freedom can be approximated using a simple Fitts' law equivalent. The rotational and translational components appear to be coordinated by the central nervous system to generate a parallel execution. Application: The results may help drive human interface designs and provide insights into the coordination of combined movements. Future extensions may be possible for the movements of higher degrees of freedom used in robot teleoperation and virtual reality applications.This work was supported by the Institute for Dexterous Space Robotics (Grant No. NNX06AD23G).Publicad

Pointing Devices for Wearable Computers

We present a survey of pointing devices for wearable computers, which are body-mounted devices that users can access at any time. Since traditional pointing devices (i.e., mouse, touchpad, and trackpoint) were designed to be used on a steady and flat surface, they are inappropriate for wearable computers. Just as the advent of laptops resulted in the development of the touchpad and trackpoint, the emergence of wearable computers is leading to the development of pointing devices designed for them. However, unlike laptops, since wearable computers are operated from different body positions under different environmental conditions for different uses, researchers have developed a variety of innovative pointing devices for wearable computers characterized by their sensing mechanism, control mechanism, and form factor. We survey a representative set of pointing devices for wearable computers using an “adaptation of traditional devices” versus “new devices” dichotomy and study devices according to their control and sensing mechanisms and form factor. The objective of this paper is to showcase a variety of pointing devices developed for wearable computers and bring structure to the design space for wearable pointing devices. We conclude that a de facto pointing device for wearable computers, unlike laptops, is not likely to emerge

HCI models, theories, and frameworks: Toward a multidisciplinary science

Motivation The movement of body and limbs is inescapable in human-computer interaction (HCI). Whether browsing the web or intensively entering and editing text in a document, our arms, wrists, and fingers are at work on the keyboard, mouse, and desktop. Our head, neck, and eyes move about attending to feedback marking our progress. This chapter is motivated by the need to match the movement limits, capabilities, and potential of humans with input devices and interaction techniques on computing systems. Our focus is on models of human movement relevant to human-computer interaction. Some of the models discussed emerged from basic research in experimental psychology, whereas others emerged from, and were motivated by, the specific need in HCI to model the interaction between users and physical devices, such as mice and keyboards. As much as we focus on specific models of human movement and user interaction with devices, this chapter is also about models in general. We will say a lot about the nature of models, what they are, and why they are important tools for the research and development of humancomputer interfaces. Overview: Models and Modeling By its very nature, a model is a simplification of reality. However a model is useful only if it helps in designing, evaluating, or otherwise providing a basis for understanding the behaviour of a complex artifact such as a computer system. It is convenient to think of models as lying in a continuum, with analogy and metaphor at one end and mathematical equations at the other. Most models lie somewhere in-between. Toward the metaphoric end are descriptive models; toward the mathematical end are predictive models. These two categories are our particular focus in this chapter, and we shall visit a few examples of each. Two models will be presented in detail and in case studies: Fitts&apos; model of the information processing capability of the human motor system and Guiard&apos;s model of bimanual control. Fitts&apos; model is a mathematical expression emerging from the rigors of probability theory. It is a predictive model at the mathematical end of the continuum, to be sure, yet when applied as a model of human movement it has characteristics of a metaphor. Guiard&apos;s model emerged from a detailed analysis of how human&apos;s use their hands in everyday tasks, such as writing, drawing, playing a sport, or manipulating objects. It is a descriptive model, lacking in mathematical rigor but rich in expressive power

Pointing Devices for Wearable Computers

We present a survey of pointing devices for wearable computers, which are body-mounted devices that users can access at any time. Since traditional pointing devices (i.e., mouse, touchpad, and trackpoint) were designed to be used on a steady and flat surface they are inappropriate for wearable computers. Just as the advent of laptops resulted in the development of the touchpad and trackpoint, the emergence of wearable computers is leading to the development of pointing devices designed for them. However, unlike laptops, since wearable computers are operated from different body positions under different environmental conditions for different uses, researchers have developed a variety of innovative pointing devices for wearable computers characterized by their sensing mechanism, control mechanism, and form factor. We survey a representative set of pointing devices for wearable computers using an “adaptation of traditional devices” versus “new devices” dichotomy and study devices according to their control and sensing mechanisms and form factor. The objective of this paper is to showcase a variety of pointing devices developed for wearable computers and bring structure to the design space for wearable pointing devices. We conclude that a de facto pointing device for wearable computers, unlike laptops, is not likely to emerge

User-defined transfer functions to improve pointing performance in graphical user interfaces

Pointing at a target is the most fundamental and frequent task in graphical user interfaces (GUIs). Pointing devices like the mouse is the most popular and cheapest input devices for current desktop computers and the touchpad or trackpad is the best match between performance and demand of pointing devices for laptop computers. Due to the widespread and frequent use of pointing devices, even a small improvement in pointing performance can have a large effect on a system's usability. The physical movement of a mouse or dragging motion of a finger on a touchpad is translated into the movement of a pointer on the graphical display through so-called transfer functions. Transfer functions are actually the only pointing facilitation technique available to all users in modern days operating systems. Despite the importance of transfer functions, very little is known about the nature of the optimal transfer functions. Pointer acceleration (PA) is the default behavior on the Microsoft Windows and Apple macOS operating systems. It dynamically manipulates the Control-Display (CD) gain between the input device and the pointer as a function of the device's velocity. This mechanism has been implemented in modern desktop user interfaces and increases the CD gain as the user's hand or finger velocity increases. Previous work showed that the default functions of Windows, Apple macOS and Xorg (the X.Org Foundation server) have shown better performance compared to a constant CD gain. Apple macOS has the improvised performance for small target widths but reduces performance for covering the long distances. Current knowledge on velocity based transfer functions relies on evaluations of basic functions and adapting the CD gain in discrete or continuous ways using low-order polynomials. The internal details and design rationales of the transfer functions that we all use are mostly unknown. The aim of this thesis is to gain a deeper understanding of the optimal transfer functions and to assess them based on natural interaction with the system using a user-driven approach. The implementation part of the thesis is divided into two desktop applications, one is for recording all raw mouse and pointer movement as well as recording contextual information to understand a transfer function. The other implementation part of the thesis is to enable the user to define their own transfer functions. Users can customize existing default transfer functions and use them to control the pointer. These two applications are used to conduct a study that collects user device information and as well as user-defined transfer functions. Finally, we identify interesting transfer function for touchpads and mice