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There are many challenges that researchers face when adapting from academic backgrounds to industry. How do we train newcomers to this field to focus on goals in context of their business’s needs? How do we ensure impact early in their career? How do we learn to look beyond the process, methods, mindset, and story-telling, to delivering on corporations’ anticipated needs? What are the challenges when mandating practitioners’ research to translate to actionable items? How do practitioners drive impact that brings the desired value to their corporations? How does one encourage user experience (UX) as an integral process within corporations’ development plans? This panel of practitioners will share the trials and tribulations they have encountered while successfully navigating their respective Human Factors and Ergonomics (HFE) careers. This panel represents peers with diverse experiences from careers in technology, product design, human-computer interfaces (HCI), medical devices, usability testing, and human factors research.

This panel includes five practitioners who publish across multiple venues. The purpose of this panel is to discuss with practitioners the challenges associated with publishing under restricted settings, such as when they are operating under non-disclosure agreements, to help them learn potential avenues to publish. The panelists represent practitioners with diverse backgrounds and approaches to publishing. The avenues for publication include traditional outlets like peer-reviewed journals and less traditional outlets like patents, magazines, and blog posts. Publishing our work, in whatever medium, can be a great way to enhance the power of the human factors community by sharing our methods and findings with colleagues and those seeking to learn more about human factors and user experience!

This paper explores the human capacity to use visual feedback to compensate for directional mismatches between input devices and cursor motions in a standardized pointing task. Sixteen participants completed blocks of 64 trials as the directional mismatch between the input device and cursor motion was incremented clockwise by 7.5° over thirteen blocks, from 0° to 90°. At 90°, a vertical motion of the mouse mapped to a cursor motion directly to the right. Participants were robust to these acclimated directional mismatches up to 30°, at which point pointing performance began to decline. The findings have application in understanding the robustness of traditional input methods, as well as in virtual reality where visual feedback mismatches can be used for steering physical motions to make better use of constrained physical space or to reuse tactile stimuli.

Background Modern computer users use the mouse almost three times as much as the keyboard. As exposure rates are high, improving upper extremity posture while using a computer mouse is desirable due to the fact that posture is one risk factor for injury. Previous studies have found posture benefits associated with using alternative mouse designs, but at the cost of performance and preference. Objective To develop new computer mouse shapes, evaluate them versus benchmarks, and determine whether there are differences in wrist posture, pointing performance, and subjective measures. Methods Three concept mice were designed and evaluated relative to two existing benchmark models: a traditional flat mouse, and an alternative upright mouse. Using a repeated measures design, twelve subjects performed a standardized point-and-click task with each mouse. Pointing performance and wrist posture was measured, along with perceived fatigue ratings and subjective preferences pre and post use. Results All of the concept mice were shown to reduce forearm pronation relative to the traditional flat mouse. There were no differences in pointing performance between the traditional flat mouse and the concept mice. In contrast, the fully vertical mouse reduced pronation but had the poorest pointing performance. Perceived fatigue and subjective preferences were consistently better for one concept mouse. Conclusions Increasing mouse height and angling the mouse topcase can improve wrist posture without negatively affecting performance.

The purpose of this study was to evaluate the effects of tactile landmarks and tactile feedback on keyboard typing under real-world conditions. Four keyboards were tested, representing a range of tactile landmarks versus no landmarks, tactile feedback versus no tactile feedback, and the ability to rest the fingers on the keys vs. keys that triggered when simply touched. Participants completed a typing task on each of the keyboards while their performance and preference was collected. The conventional keyboard with tactile landmarks, tactile feedback, and the ability to rest the fingers was significantly better than the other options both in terms of performance and preference. The capacitive keyboard, which had tactile landmarks but no tactile feedback, nor the ability to rest fingers on the keys without triggering them performed the worst in terms of accuracy and preference, showing that tactile landmarks alone do not ensure good performance.

Tablets computers are being rapidly adopted in commercial and home settings. However, there are no guidelines on design features of tablets to optimize usability. The purpose of this study was to evaluate tablet size, weight, orientation, grip shape, texture, and stylus shape on productivity, usability, and biomechanics when the tablet is held with just the left hand. Thirty subjects tested eight tablets and three styluses. Overall, the usability, fatigue and biomechanical evaluation of tablet design features supported the use of smaller to medium sized tablets, with a ledge or handle shape on the back and surfaced with a rubberized texture. Larger tablets had significantly worse usability and biomechanics. The stylus with a tapered grip (7.5-9.5 mm) or larger grip (7.6 mm) had better usability and biomechanics than one with a smaller grip (5 mm). These design parameters may be important when designing tablets that will be held with one hand.

BACKGROUND: Due to its rapid growth in popularity, there is an imminent need for ergonomic evaluation of the touch-screen tablet computing form-factor. OBJECTIVE: The aim of this study was to assess postures of the shoulders and wrists and their associated muscle activity during touch-screen tablet use. METHODS: Fifteen experienced adult tablet users completed a set of simulated software tasks on two media tablets in a total of seven user configurations. Configurations consisted of a combination of a support condition (held with one hand, two hands or in a case), a location (on the lap or table surface), and a software task (web browsing, email, and game). Shoulder postures were measured by using an infra-red LED marker based motion analysis system, wrist postures by electro-goniometry, and shoulder (upper trapezius and anterior deltoid) and forearm (flexor carpi radialis, flexor carp ulnaris, and extensor radialis) muscle activity by surface electromyography. RESULTS: Postures and muscle activity for the wrist significantly varied across configurations and between hands, but not across the two tablets tested. Wrist extension was high for all configurations and particularly for the dominant hand when a tablet was placed on the lap (mean = 38 ◦ ). Software tasks involving the virtual keyboard (e-mailing) corresponded to higher wrist extensor muscle activity (50 th percentile = 9.5% MVC) and wrist flexion/extension acceleration (mean = 322 ◦ /s 2 ). High levels of wrist radial deviation were observed for the non-dominant hand when it was used to tilt and hold the tablet (mean = 13 ◦ ). Observed differences in posture and muscle activity of the shoulder were driven by tablet location. CONCLUSION: Touch-screen tablet users are exposed to extreme wrist postures that are less neutral than other computing technologies and may be at greater risk of developing musculoskeletal symptoms. Tablets should be placed in cases or stands that adjust the tilt of the screen rather than supporting and tilting the tablet with only one hand.

Holding a tablet computer in two hands and interacting via the thumbs is an important and commonly observed method of tablet interaction. This paper presents a methodology for measuring and reporting thumb reach in a way that enables designers of user interfaces (UI) to design UIs that can be comfortably reached by the thumbs. The process is to identify the relevant anthropometric measure and target population, identify how people grip the device, measure reach areas for different groups and grips, and to use the data to create graphical ‘heat maps’ along with guidance that designers can use to place their interface elements into easily reachable areas of the screen. The methodology is illustrated with an example of how it was used in the development of Microsoft Windows 8.

International standards that specify the spacing between keys on a keyboard have been guided primarily by design convention. Experienced typists (N=37) with large hands typed on five keyboards with different horizontal and vertical key spacing (19x19, 18x19, 17x19, 16x19, and 17x17mm) while productivity, comfort ratings, left and right extensor carpi ulnaris (ECU) and flexor carpi ulnaris (FCU) muscle forces, and right and left wrist extension and ulnar deviation were recorded. Productivity and usability ratings were significantly worse for the 16x19 keyboard. There was a trend for muscle activity to increase in the left forearm and decrease in the right forearm with decreasing horizontal key spacing. There was also a trend for left wrist extension to increase and left ulnar deviation to decrease with decreasing horizontal key spacing. The study findings support key spacing on a keyboard between 17 and 19mm. These findings may influence keyboard standards and design of keyboards.

OBJECTIVE: This article aims to provide designers and researchers with a summary of the current literature regarding the effects of specific keyswitch design parameters on user preference, performance, and biomechanical outcomes. METHODS: Studies which evaluated the effects of keyswitch make force, make travel and over travel on preference, typing speed, errors, keyboard reaction forces and upper extremity EMG are included in the review. Studies which examined possible control strategies employed during keyswitch tapping are also covered. RESULTS: General conclusions that can be drawn from these studies are: greater make forces result in increased keyboard reaction forces and EMG activity, users strike keys with forces 2-7 times the required make force and that they employ a ballistic finger motion to do so. Furthermore, typists tend to prefer kinesthetic and auditory feedback. CONCLUSIONS: Due to the ballistic nature of typing, new keyswitch designs should be aimed at reducing impact forces. Future studies should examine the role of breakaway force and over travel as limited research has been done on the role of these parameters.

This study quantified postures of users working on a notebook computer situated in their lap and tested the effect of using a device designed to increase the height of the notebook when placed on the lap. A motion analysis system measured head, neck and upper extremity postures of 15 adults as they worked on a notebook computer placed on a desk (DESK), the lap (LAP) and a commercially available lapdesk (LAPDESK). Compared with the DESK, the LAP increased downwards head tilt 6 degrees and wrist extension 8 degrees . Shoulder flexion and ulnar deviation decreased 13 degrees and 9 degrees , respectively. Compared with the LAP, the LAPDESK decreased downwards head tilt 4 degrees , neck flexion 2 degrees , and wrist extension 9 degrees. Users reported less discomfort and difficulty in the DESK configuration. Use of the lapdesk improved postures compared with the lap; however, all configurations resulted in high values of wrist extension, wrist deviation and downwards head tilt. STATEMENT OF RELEVANCE: This study quantifies postures of users working with a notebook computer in typical portable configurations. A better understanding of the postures assumed during notebook computer use can improve usage guidelines to reduce the risk of musculoskeletal injuries.

Rapid Prototyping (RP) technologies provide the ability to fabricate initial prototypes from various model materials. Stratasys Fused Deposition Modeling (FDM) is a typical RP process that can fabricate prototypes out of ABS plastic. To predict the mechanical behavior of FDM parts, it is critical to understand the material properties of the raw FDM process material, and the effect that FDM build parameters have on anisotropic material properties. This paper characterizes the properties of ABS parts fabricated by the FDM 1650. Using a Design of Experiment (DOE) approach, the process parameters of FDM, such as raster orientation, air gap, bead width, color, and model temperature were examined. Tensile strengths and compressive strengths of directionally fabricated specimens were measured and compared with injection molded FDM ABS P400 material. For the FDM parts made with a 0.003 inch overlap between roads, the typical tensile strength ranged between 65 and 72 percent of the strength of injection molded ABS P400. The compressive strength ranged from 80 to 90 percent of the injection molded FDM ABS. Several build rules for designing FDM parts were formulated based on experimental results.

The purpose of this study was to evaluate tablet size (weight), orientation, grip shape, texture and stylus shape on productivity, biomechanics and subjective usability and fatigue when the tablet was held with just the left hand. A total of 15 male and 15 female subjects, ages 16-64 years, tested eight tablets and three styluses. Overall, the usability, fatigue and biomechanical evaluation of tablet design features supported the use of smaller to medium-sized tablets, with a ledge or handle shape on the back and surfaced with a rubberised texture. Larger, heavier tablets had significantly worse usability and biomechanics and their use with one hand should be limited. The stylus with a tapered grip (7.5-9.5 mm) or larger grip (7.6 mm) had better usability and biomechanics than one with a smaller grip (5 mm). There were no significant differences in productivity between design features. These design parameters may be important when designing tablets.Different tablet and stylus design features were evaluated for usability and biomechanical properties. On the basis of short-term tasks, emulating functional tablets, usability was improved with the smaller and medium-sized tablets, portrait (vs. landscape) orientation, a back ledge grip and rubberised texture. There were no differences in productivity between design features.

Objective: The aim of this study was to determine how head and neck postures vary when using two media tablet (slate) computers in four common user configurations. Methods: Fifteen experienced media tablet users completed a set of simulated tasks with two media tablets in four typical user configurations. The four configurations were: on the lap and held with the user's hands, on the lap and in a case, on a table and in a case, and on a table and in a case set at a high angle for watching movies. An infra-red LED marker based motion analysis system measured head/neck postures. Results: Head and neck flexion significantly varied across the four configurations and across the two tablets tested. Head and neck flexion angles during tablet use were greater, in general, than angles previously reported for desktop and notebook computing. Postural differences between tablets were driven by case designs, which provided significantly different tilt angles, while postural differences between configurations were driven by gaze and viewing angles. Conclusion: Head and neck posture during tablet computing can be improved by placing the tablet higher to avoid low gaze angles (i.e. on a table rather than on the lap) and through the use of a case that provides optimal viewing angles.

This study evaluated the use of simple inclines as a portable peripheral for improving head and neck postures during notebook computer use on tables in portable environments such as hotel rooms, cafes, and airport lounges. A 3D motion analysis system measured head, neck and right upper extremity postures of 15 participants as they completed a 10 min computer task in six different configurations, all on a fixed height desk: no-incline, 12° incline, 25° incline, no-incline with external mouse, 25° incline with an external mouse, and a commercially available riser with external mouse and keyboard. After completion of the task, subjects rated the configuration for comfort and ease of use and indicated perceived discomfort in several body segments. Compared to the no-incline configuration, use of the 12° incline reduced forward head tilt and neck flexion while increasing wrist extension. The 25° incline further reduced head tilt and neck flexion while further increasing wrist extension. The 25° incline received the lowest comfort and ease of use ratings and the highest perceived discomfort score. For portable, temporary computing environments where internal input devices are used, users may find improved head and neck postures with acceptable wrist extension postures with the utilization of a 12° incline.

This study examines the home computer use of 26 children (aged 6-18) in ten upper middle class families using direct observation, typing tests, questionnaires and semi-structured interviews. The goals of the study were to gather information on how children use computers in the home and to understand how both parents and children perceive this computer use. Large variations were seen in computing skills, behaviors, and opinions, as well as equipment and workstation setups. Typing speed averaged over 40 words per minute for children over 13 years old, and less than 10 words per minute for children younger than 10. The results show that for this sample, Repetitive Stress Injury (RSI) concerns ranked very low among parents, whereas security and privacy concerns ranked much higher. Meanwhile, children's behaviors and workstations were observed to place children in awkward working postures. Photos showing common postures are presented. The greatest opportunity to improve children's work postures appears to be in providing properly-sized work surfaces and chairs, as well as education. Possible explanations for the difference between parental perception of computing risks and the physical reality of children's observed ergonomics are discussed and ideas for further research are proposed.

Split, gabled keyboard designs can prevent or improve upper extremity pain among computer users; the mechanism appears to involve the reduction of awkward wrist and forearm postures. This study evaluated the effects of changes in opening angle, slope and height (independent variables) of a gabled (14 degrees) keyboard on typing performance and upper extremity postures. Twenty-four experienced touch typists typed on seven keyboard conditions while typing speed and right and left wrist extension, ulnar deviation, forearm pronation and elbow position were measured using a motion tracking system. The lower keyboard height led to a lower elbow height (i.e. less shoulder elevation) and less wrist ulnar deviation and forearm pronation. Keyboard slope and opening angle had mixed effects on wrist extension and ulnar deviation, forearm pronation and elbow height and separation. The findings suggest that in order to optimise wrist, forearm and upper arm postures on a split, gabled keyboard, the keyboard should be set to the lowest height of the two heights tested. Keyboard slopes in the mid-range of those tested, 0 degrees to -4 degrees, provided the least wrist extension, forearm pronation and the lowest elbow height. A keyboard opening angle in the mid-range of those tested, 15 degrees, may provide the best balance between reducing ulnar deviation while not increasing forearm pronation or elbow separation. These findings may be useful in the design of computer workstations and split keyboards. The geometry of a split keyboard can influence wrist and forearm postures. The findings of this study are relevant to the positioning and adjustment of split keyboards. The findings will also be useful for engineers who design split keyboards.

Background. Extensive computer mouse use is an identified risk factor for computer work-related musculoskeletal disorders; however, notebook computer mouse designs of varying sizes have not been formally evaluated but may affect biomechanical risk factors. Methods. Thirty adults performed a set of mouse tasks with five notebook mice, ranging in length from 75 to 105 mm and in width from 35 to 65 mm, and a reference desktop mouse. An electro-magnetic motion analysis system measured index finger (metacarpophalangeal joint), wrist and forearm postures, and surface electromyography measured muscle activity of three extensor muscles in the forearm and the first dorsal interrosseus. Findings. The smallest notebook mice were found to promote less neutral postures (up to 3.2° higher metacarpophalangeal joint adduction; 6.5° higher metacarpophalangeal joint flexion, 2.3° higher wrist extension) and higher muscle activity (up to 4.1% of maximum voluntary contraction higher wrist extensor muscle activity). Participants with smaller hands had overall more non-neutral postures than participants with larger hands (up to 5.6° higher wrist extension and 5.9° higher pronation); while participants with larger hands were more influenced by the smallest notebook mice (up to 3.6° higher wrist extension and 5.5% of maximum voluntary contraction higher wrist extensor values). Self-reported ratings showed that while participants preferred smaller mice for portability; larger mice scored higher on comfort and usability. Interpretation. The smallest notebook mice increased the intensity of biomechanical exposures. Longer term mouse use could enhance these differences, having a potential impact on the prevention of work-related musculoskeletal disorders. © 2008 Elsevier Ltd. All rights reserved.

The goal of this study was to determine whether a new dynamic arm support system reduced shoulder and arm muscle load for seated and standing hand/ arm tasks. The new system provides support for both horizontal and vertical arm motion. A total of 11 participants performed ten tasks (five seated and five standing) both with and without the arm support. Outcomes were assessed with electromyography and subjective feedback. Muscle activity was measured over the dominant side supraspinatus, triceps and forearm extensor muscles. Significant (p < 0.01) reductions in static muscle activity were observed in one of ten tasks performed with the support device for the supraspinatus muscle, in five tasks for the triceps and in one task for forearm extensor muscles. Likewise, a significant improvement in subjective measures was reported with the support device for 'ease of task' for two of ten tasks, for 'forearm comfort' for three of ten tasks and for 'shoulder effort' for six of ten tasks. The results suggest that a dynamic forearm support may improve subjective comfort and reduce static muscle loads in the upper extremity for tasks that involve horizontal movement of the arms. For rapid motions, the value of the support is limited due to internal inertia and friction.