Liberty Mutual Research Institute for Safety

Hopkinton, MA, United States

Liberty Mutual Research Institute for Safety

Hopkinton, MA, United States
Time filter
Source Type

Liang Y.,Liberty Mutual Research Institute for Safety | Lee J.D.,University of Wisconsin - Madison | Yekhshatyan L.,University of Iowa
Human Factors | Year: 2012

Objective: In this study, the authors used algorithms to estimate driver distraction and predict crash and near-crash risk on the basis of driver glance behavior using the data set of the 100-Car Naturalistic Driving Study. Background: Driver distraction has been a leading cause of motor vehicle crashes, but the relationship between distractions and crash risk lacks detailed quantification. Method: The authors compared 24 algorithms that varied according to how they incorporated three potential contributors to distraction\-glance duration, glance history, and glance location\-on how well the algorithms predicted crash risk. Results: Distraction estimated from driver eyeglance patterns was positively associated with crash risk. The algorithms incorporating ongoing off-road glance duration predicted crash risk better than did the algorithms incorporating glance history. Augmenting glance duration with other elements of glance behavior-1.5th power of duration and duration weighted by glance location\-produced similar prediction performance as glance duration alone. Conclusions: The distraction level estimated by the algorithms that include current glance duration provides the most sensitive indicator of crash risk. Application: The results inform the design of algorithms to monitor driver state that support realtime distraction mitigation systems. © 2012, Human Factors and Ergonomics Society.

Based on UC Berkeley engineering research, MAX (Modular Agile Exoskeleton) combines back, shoulder and leg components to form the only passive industrial exoskeleton currently available BERKELEY, CA--(Marketwired - Nov 16, 2016) - suitX, a California-based robotics company designing and manufacturing medical and industrial exoskeletons, announced today the official launch of MAX, a flexible exoskeleton that can be adapted to a variety of workplace tasks. MAX comprises three exoskeleton modules: backX, shoulderX, and legX. Each module can be worn independently and in any combination depending on need. All modules intelligently engage when you need them, and don't impede you otherwise. MAX's lightweight design and versatile modules bring support to strenuous activities including lifting, stooping, bending, squatting and overhead work allowing workers to be more productive by reducing fatigue and costly workplace injuries. This new development in the suitX portfolio follows the introduction of Phoenix, the suitX lightweight medical-grade exoskeleton designed to aid people with mobility disorders. Liberty Mutual Research Institute for Safety reports that, in 2013, overexertion ranked first among the leading causes of disabling injury. Lifting, pushing, pulling, holding, or carrying objects cost businesses $15.08 billion in direct costs and accounted for nearly a quarter of the overall national burden. Assistive bionics technologies such as MAX have the potential to improve quality of life, decrease at-work injury claims, and create a safer, more productive workplace environment. A recent study by researchers at the University of California, Berkeley showed the backX component of the MAX system augmented users with an average 60% reduction in muscle activities at four of the lower back muscle groups. MAX and its products are expected to benefit workers in many industrial settings including construction, airports, assembly lines, shipbuilding, warehouses, delivery services and factories. MAX is very comfortable; workers can wear MAX modules all day and continue to perform everyday tasks without any impairment. "The MAX solution is designed for unstructured workplaces where no robot can work as efficiently as a human worker. Our goal is to augment and support workers who perform demanding and repetitive tasks in unstructured workplaces in order to prevent and reduce injuries," explained Dr. Homayoon Kazerooni, founder and CEO, suitX. "We have created responsive and affordable technologies to augment workers' strength while leaving the worker in control of the operation. MAX is designed to support workers during the repetitive tasks that most frequently cause injury. It's not only lifting 75 pounds that can hurt your back; it is also lifting 20 pounds repeatedly throughout the day that will lead to injury," said Kazerooni. Countless field evaluations conducted at construction, material handling, shipbuilding, foundry, and airport baggage handling sites in the US and Japan, as well as extensive research in Berkeley led to the development of MAX modules. Effective and comfortable, all MAX modules augment workers and give them the means to work more safely and productively. The initial funding to develop MAX was provided from various sources, including a grant from National Science Foundation under a National Robotics Initiative (NRI) program announced by the White House in 2011. MAX won two Saint-Gobain NOVA Innovation Awards for its intelligent design, effectiveness and affordability. "We believe MAX will become the exoskeleton technology gold-standard in reducing on-the-job injuries and improving workplace quality of life," said Dr. Kazerooni. About suitX suitX is a robotics company designing and manufacturing both medical and industrial exoskeletons that address common problems faced by workers and people with gait impairment to improve everyday life. suitX has received Series A investments, been awarded a few US government awards, and won two Saint Gobain Nova Innovation Awards. suitX also won the $1M USD Top Prize in the UAE AI and Robotics for Good Competition. suitX is currently looking for prominent strategic partners and financiers for global expansion. For more information, visit

Besen E.,Liberty Mutual Research Institute for Safety | Pransky G.,Liberty Mutual Research Institute for Safety
Scandinavian Journal of Work, Environment and Health | Year: 2014

Objectives We investigated multiple trajectories of the probability of reporting health-related productivity loss over a 20-year period among adults aged 25-44 years and explored differences among the trajectories in demographic and personal characteristics and employment outcomes in midlife. Methods A latent class growth analysis of health-related productivity loss was estimated on 12 waves of data from the National Longitudinal Survey of Youth (NLSY79) (N=5699), an ongoing nationally representative longitudinal survey of Americans. Waves 1-5 were collected annually at ages 25-29 years. Waves 6-12 were collected biennially at ages 30-44 years. Productivity loss was measured as "health fully preventing a person from working" or "health limiting the amount or kind of work a person could do". Differences among trajectories were assessed using analyses of variance (ANOVA) and Chi-square tests. Results A five-group trajectory model for productivity loss was identified: (i) no risk, (ii) low risk, (iii) high risk, (iv) increasing risk at early ages, and (v) increasing risk at later ages. At the first wave, after the waves used for the trajectory model in which respondents were approximately age 45 years, the no- and low-risk groups worked the most weeks and hours per week and had the highest percentages of participants employed ≥10 weeks compared to the high-risk and early-/late-onset increasing-risk groups, all of which had the lowest levels of mastery, self-esteem, education, and socioeconomic status. Conclusions There are several developmental patterns of productivity loss, with some trajectories being associated with lower work participation in midlife. These high risk patterns may be indicative of individuals needing intervention to prevent premature work withdrawal.

Young A.E.,Liberty Mutual Research Institute for Safety
Scandinavian Journal of Work, Environment and Health | Year: 2010

Objective: Return to work following occupational injury is an important rehabilitation milestone; however, it does not mark the end of the return-to-work process. Following a return to the workplace, workers can experience difficulties that compromise their rehabilitation gains. Although there has been investigation of factors related to a return to the workplace, little attention has been paid to understanding what facilitates continued return-to-work success as this paper aims to do. Methods: This study used data gathered during one-on-one telephone interviews with 146 people who experienced a work-related injury that resulted in their being unable to return to their pre-injury job, but who returned to work following an extended period of absence and the receipt of vocational services. Results: Numerous return-to-work facilitators were reported, including features of the workers' environmental and personal contexts, as well as body function, activities, and participation. Influences that stood out included a perception that the work was appropriate, supportive workplace relationships, and a sense of satisfaction/achievement associated with being at work. Conclusions: The findings support the contention that initiatives aimed at improving return-to-work outcomes can go beyond the removal of barriers to include interventions to circumvent difficulties before they are encountered. Together with providing ideas for interventions, the study's findings offer an insight into research and theoretical development that might be undertaken to further the understanding of the return-to-work process and the factors that impact upon it.

Maikala R.V.,Liberty Mutual Research Institute for Safety
International Journal of Industrial Ergonomics | Year: 2010

Studying the interaction of light with human tissue is important in understanding functional changes and oxidative metabolism of tissue (e.g., skeletal muscle, brain). This manuscript focuses on the development of quantitative absorption laws of light energy, from the inception of Bouguer Law to Beer's Law, to gain a perspective on the present application of the absorption concepts in investigating optical properties of light absorbing chromophores of human tissue. Although these absorption laws are applicable to determine the absolute concentration of substances present in solids or solvents, these laws do not take into consideration of either reflection or scattering of incident light that accounts for the loss of transmitted light intensity. Importance of light energy in the near-infrared window of 700-1300 nm compared to that of other regions in the electromagnetic spectrum for determination of optical tissue properties in vivo is emphasized. Since human tissue is a highly scattering non-homogenous medium, limitations of Beer's Law with respect to studying human tissue chromophores are presented. Finally, modifications of Beer's Law to investigate the relationship between changes in absorbency and concentrations of light absorbing chromophores within the medical spectral window (700-900 nm) in human tissue are discussed. Relevance to industry: As light propagates through human tissue, concentration of some chromophores varies in time within the medical spectral window, implying physiological changes in the tissue. Utilization of this optical principle in biomedical (non-invasive) research of the health and disease of human tissue has increased in the last two decades. While impressive in clinical applications, researchers in the field of ergonomics and human factors have been slow in exploiting the potential of examining optical properties of tissue relevant to human performance at the workplace. © 2009 Elsevier B.V. All rights reserved.

Zohar D.,Liberty Mutual Research Institute for Safety | Zohar D.,Technion - Israel Institute of Technology
Accident Analysis and Prevention | Year: 2010

Looking back over 30 years of my own and other safety-climate scholars' research, my primary reflection is that we have achieved an enormous task of validating safety climate as a robust leading indicator or predictor of safety outcomes across industries and countries. The time has therefore come for moving to the next phase of scientific inquiry in which constructs are being augmented by testing its relationships with antecedents, moderators and mediators, as well as relationships with other established constructs. Whereas there has been some significant progress in this direction over the last 30 years (e.g. leadership as a climate antecedent), much more work is required for augmenting safety climate theory. I hope this article will stimulate further work along these lines. © 2009 Elsevier Ltd. All rights reserved.

Xu X.,Liberty Mutual Research Institute for Safety | McGorry R.W.,Liberty Mutual Research Institute for Safety
Applied Ergonomics | Year: 2015

The Kinect sensor released by Microsoft is a low-cost, portable, and marker-less motion tracking system for the video game industry. Since the first generation Kinect sensor was released in 2010, many studies have been conducted to examine the validity of this sensor when used to measure body movement in different research areas. In 2014, Microsoft released the computer-used second generation Kinect sensor with a better resolution for the depth sensor. However, very few studies have performed a direct comparison between all the Kinect sensor-identified joint center locations and their corresponding motion tracking system-identified counterparts, the result of which may provide some insight into the error of the Kinect-identified segment length, joint angles, as well as the feasibility of adapting inverse dynamics to Kinect-identified joint centers. The purpose of the current study is to first propose a method to align the coordinate system of the Kinect sensor with respect to the global coordinate system of a motion tracking system, and then to examine the accuracy of the Kinect sensor-identified coordinates of joint locations during 8 standing and 8 sitting postures of daily activities. The results indicate the proposed alignment method can effectively align the Kinect sensor with respect to the motion tracking system. The accuracy level of the Kinect-identified joint center location is posture-dependent and joint-dependent. For upright standing posture, the average error across all the participants and all Kinect-identified joint centers is 76mm and 87mm for the first and second generation Kinect sensor, respectively. In general, standing postures can be identified with better accuracy than sitting postures, and the identification accuracy of the joints of the upper extremities is better than for the lower extremities. This result may provide some information regarding the feasibility of using the Kinect sensor in future studies. © 2015 Elsevier Ltd and The Ergonomics Society.

Young A.E.,Liberty Mutual Research Institute for Safety
Disability and Rehabilitation | Year: 2010

Purpose: To determine post-return-to-work disability and functioning amongst occupationally injured workers and to test the extent to which demographic and other variables relate to employment maintenance. In addition, the project sought to document what workers believe determined their work continuation. Method: Semi-structured in-depth interviews were conducted to inquire about participant's (N150) post-vocational rehabilitation return-to-work experiences. Results were interpreted using the health and health-related domains from the International Classification of Functioning, Disability and Health. Results: Although most participants were working at the time of interview, almost all were experiencing functional- or activity-based restrictions. Factors differentiating those employed from those not, were largely contextual and included relationships with supervisors, economic climate, and working conditions. Conclusions.The findings stress the importance of considering environmental strains when planning return to work and indicate ways to assist workers to achieve return-to-work success. © 2010 Informa UK, Ltd.

McGorry R.W.,Liberty Mutual Research Institute for Safety
Journal of occupational and environmental hygiene | Year: 2010

The gripping of tools is required by many industrial operations, and an important aspect of exposure assessment is determining the grip force output of operators. Ratings of perceived exertion can provide an indirect measure of grip force; however, reports in the literature of the use of Borg CR10 scale ratings as a surrogate measure of grip force have been mixed. During a laboratory study with 16 participants, power grip forces were measured directly during three hand tool task simulations: (1) a screwdriver task, (2) a ratchet task, and (3) a lift and carry task, each performed at four force/load levels. Borg scale ratings reported following each trial were compared with mean, peak, and integrated grip forces for the respective trials. Pearson correlations conducted on an individual basis were greatest for the screwdriver task, r approximately 0.9. Correlations for integrated grip force were generally better than for mean or peak force. Correlations were also performed on data pooled for all participants, simulating a cross-sectional sampling approach. Correlations made with pooled data were weaker than when conducted on an individual basis, ranging from r = 0.26 for peak grip force for the lift and carry task, to r = 0.79 for the screwdriver task. When the pooled data were normalized to individual maximum voluntary grip exertions, correlation generally improved but not to the level of the "individually scaled" data. Based on these findings, a protocol is proposed that could improve the strength of correlations between direct measures of grip force and ratings of perceived exertion. Differences in strength of correlation between task simulations are discussed with respect to differences observed in force distributions about the handle for the three tasks.

Maikala R.V.,Liberty Mutual Research Institute for Safety
Journal of Near Infrared Spectroscopy | Year: 2012

The potential application of near infrared (NIR) spectroscopy has opened doors for many research investigations related to occupational health, specifically in low back muscle research. This review addressed haemodynamic measurements of paraspinal muscles within the context of low back musculoskeletal health and disorders. Systematic online English language searches were conducted using MEDLINE, EMBASE, ScienceDirect and Scopus. A study was included if it was focused on NIR spectroscopy application to the back region and was also published in the English language. A study was excluded if the main focus was either on upper/lower extremity specific investigations, or the experimental protocol was ambiguous, or the measures utilised were other than spectroscopy-derived haemodynamics. In total, 37low back studies were included in the review. Studies were mainly classified into five categories: (i) postural variation, (ii) occupational exposure, (iii) aetiology of low back disorders, (iv) analysis of adipose tissue thickness on spectroscopy-derived measurements and (v) reliability of optical spectroscopy measurements. Seventeen studies were focused on the basic (patho)physiology of the low back musculature during a variety of postural variations. Thirteen studies were specific to occupational activities, whereas 10 investigations were related to low back musculoskeletal disorders. Nine studies examined the Influence of adipose tissue thickness measured at the erector spinae region on haemodynamic responses. Reliability of spectroscopy-derived responses was reported in 10 studies. This systematic review supports the need for more spectroscopy-related investigations relevant to work-related activities and specific to low back musculoskeletal disorders. Rigorous statistical analysis is needed in examining the Influence of adipose tissue thickness on haemodynamic responses. Although high reliability of spectroscopy-derived responses was found in the majority of studies, to date there are no investigations that have established their reliability in the low back pain patient population. More importantly, a proper calibration technique to identify the physiological minimum in the paraspinal muscle region is still elusive. Overall, understanding injury mechanisms for low back pain and other associated musculoskeletal disorders with NIR oximeters is still in its infancy. However, with the advent of advanced optical spectroscopy systems in the last decade, the potential for innovative use of NIR oximeters in low back musculoskeletal health-related research is promising. © IM Publications LLP 2012.

Loading Liberty Mutual Research Institute for Safety collaborators
Loading Liberty Mutual Research Institute for Safety collaborators