Reducing whole body vibration in forklift drivers

Forklift drivers in warehouses are often exposed to whole body vibration (WBV) during the total day. There is however an association between working as a forklift operator and the development of low back pain. In this study the exposure to WBV was measured in five forklift drivers who performed a standardised order picking task during 10 minutes. The effect of driving surface (uneven concrete vs. new flat concrete), driving speed (15 km/h vs. 8 km/h) and seat suspension (mechanical suspension vs. air suspension) was investigated. Improving the driving surface was the most effective preventive measure by reducing the whole body vibration with 39%, from 1.14 to 0.69 m/s2. Lowering the speed limit resulted in a reduction of WBV with 26% (1.05 vs. 0.78 m/s2). An air suspension seat was 22% more effective compared to mechanical suspension (1.02 vs. 0.80 m/s2). On uneven concrete an air suspension seat performed even better by reducing the WBV by 29% (1.33 vs. 0.95 m/s2). A combination of a new driving surface, limiting the maximum speed and the introduction of an air suspension seat reduced the whole body vibrations below the action limit of 0.5 m/s2 as mentioned in the European directive. None of the interventions were effective enough on their own.     

Adaptive information design for outdoor augmented reality

Augmented Reality focuses on the enrichment of the user's natural field of view by consistent integration of text, symbols and interactive three-dimensional objects in real time. Placing virtual objects directly into the user's view in a natural context empowers highly dynamic applications. On the other hand, this necessitates deliberate choice of information design and density, in particular for deployment in hazardous environments like military combat scenarios. As the amount of information needed is not foreseeable and strongly depends on the individual mission, an appropriate system must offer adequate adaptation capabilities. The paper presents a prototypical, vehicle-mountable Augmented Reality vision system, designed for enhancing situation awareness in stressful urban warfare scenarios. Tracking, as one of the most crucial challenges for outdoor Augmented Reality, is accomplished by means of a Differential-GPS approach while the type of display to attach can be modified, ranging from ocular displays to standard LCD mini-screens. The overall concept also includes envisioning of own troops (blue forces), for which a multi-sensor tracking approach has been chosen. As a main feature, the system allows switching between different information categories, focusing on friendly, hostile, unidentified or neutral data. Results of an empirical study on the superiority of an in-view navigation cue approach conclude the paper.     

State of scientific knowledge about the need of recovery time at specific workplaces and recommendations for further research

Research activities to determine the need of recovery time at work were mainly performed in the 1970s and 1980s. Previous studies were largely based on expert opinions or were generated within small and non-representative groups. Often, laboratory experiments were carried out with a low number of subjects. Especially during the last decade, only little additional scientific knowledge was generated on this topic. The very resource intensive development of more detailed results based on the existing level of scientific knowledge is assumed as one reason for this. In general, it seems to be reasonable to continue further research on the knowledge generated in previous studies, but implement larger samples and more representative groups. Besides, according to monotonous manual work, more research is especially needed regarding relative operating forces and operation frequencies taken grip conditions and hand/body position into account.     

The reality of the women who make our lives easier: experience in a company that assemblies electric motors in Venezuela

Objective: intervene a workline throughout ergonomic approach to diminish incidence of Carpal Tunnel Syndrome (CTS). Methods and Materials: an ergonomic intervention study was developed in workstations with highest index of musculoskeletal disorder (MED) associated to cumulative trauma. The Deparis method, Reba and Ocra check list methods were used, also morbility reviewes. National and international ethics criteria were carried out. Results: workers identified 3 fundamental issues using the Deparis method: repetitive activities, postures adopted and uncomfortable furniture. The analysis of the workstation with Reba and Ocra methods before the changes, evidenciated that 56% of postures adopted were high risk postures, the 44% remaining were medium and low-risk. Following the active pause program (APP), furniture changes and work rhythm decrease, was noted that the risk of suffering MED decreased. The morbility review, drop in consults of musculoskeletal system (MES) related to CTS observed. The APP was well accepted by women, but not initially men. Discussion: the research show that when the work rhythm decreases, the symptom of MES related to CTS have a remarkable decrease, also that changes in the furniture, generate great ergonomic differences and changes in the work environment are not possible if workers don't empower the tools to make-it.     

Prevention of MSD within OHSMS/IMS: a systematic review of risk assessment strategies

The purpose of this systematic review was to identify and summarize the research evidence on prevention of Musculoskeletal Disorders (MSD) within Occupational Health and Safety Management Systems (OHSMS) and Integrated Management Systems (IMS). Databases in business, management, engineering and health and safety were systematically searched and relevant publications were synthesized. The number of papers that could address the research questions was small. However, the review revealed that many of the techniques to address MSD hazards require substantial background knowledge and training. This may limit employees' involvement in the technical aspects of the risk assessment process. Also these techniques did not usually fit into techniques used by companies to address other risk factors within their management systems. This could result in MSD prevention becoming a separate issue that cannot be managed with company-wide tools. In addition, this review also suggested that there is a research gap concerning the MSD prevention within companies' management systems.     

Comparing swimsuits in 3D

In competitive swimming, suits have become more important. These suits influence friction, pressure and wave drag. Friction drag is related to the surface properties whereas both pressure and wave drag are greatly influenced by body shape. To find a relationship between the body shape and the drag, the anthropometry of several world class female swimmers wearing different suits was accurately defined using a 3D scanner and traditional measuring methods. The 3D scans delivered more detailed information about the body shape. On the same day the swimmers did performance tests in the water with the tested suits. Afterwards the result of the performance tests and the differences found in body shape was analyzed to determine the deformation caused by a swimsuit and its effect on the swimming performance. Although the amount of data is limited because of the few test subjects, there is an indication that the deformation of the body influences the swimming performance.     

Evaluation of objectivity, reliability and criterion validity of the key indicator method for manual handling operations (KIM-MHO), draft 2007

Upper extremity musculoskeletal symptoms and disorders are common in the working population. The economic and social impact of such disorders is considerable. Long-time, dynamic repetitive exposure of the hand-arm system during manual handling operations (MHO) alone or in combination with static and postural effort are recognised as causes of musculoskeletal symptoms and disorders. The assessment of these manual work tasks is crucial to estimate health risks of exposed employees. For these work tasks, a new method for the assessment of the working conditions was developed and a validation study was performed. The results suggest satisfying criterion validity and moderate objectivity of the KIM-MHO draft 2007. The method was modified and evaluated again. It is planned to release a new version of KIM-MHO in spring 2012.     

Virtual reality based therapy for post operative rehabilitation of children with cerebral palsy

Virtual reality is the use of interactive replication created with computer hardware and software to impart users with opportunities to engage in environments that appear to feel similar to real world objects and events. The commonest rehabilitation program of cerebral palsy children involves stretching, strengthening, mobilization and various other activities, whereas the use of virtual reality based training (VRBT) for rehabilitation of cerebral palsy is not common. To understand the effect of VRBT a study was formulated. Twenty nine subjects participated (study group--14 and control group--15). Outcome measures were MACS, PBS, level of participation, motivation, cooperation and satisfaction of the child. Results revealed that balance and manual ability were significantly improved in both the groups (Balance: study: t-2.28, p<0.05; control: t-3.5, p<0.01; Manual ability: study: t-5.58, p<0.001; control: t-7.06, p<0.001). PBS had significantly greater improvement in the study group (t-t-2.02, p<0.05). Level of participation, motivation, cooperation and satisfaction of the child were also reported to be significantly higher among the study group as compared with control group. To the author's best knowledge, this is the first study on using the VR-based therapy for the postoperative rehabilitation of children with CP which need further elaboration with larger sample size.