Get help from the best in academic writing.

Human Errors in Relation with Human-Machine Interface essay help service custom essay writing

Safety and health in Manufacturing Industry * Ramanathan Muthukaruppan 1. Introduction: The use of complex machines and systems has been ever increasing in all sectors, especially in manufacturing sector. Most of the industries go for rapid upgrades in production technology to face the global competition. Particularly, manufacturing machines in metal industry is affected by increasing complexity and increase in use of complex machines and systems. In general, the working environment has become more complex in industrial processes.

This expands beyond production section to monitoring and quality control sections of the industry as well. This results in increase in operators’ mental workload and consequently in increased risk of errors because the machine operators have to handle complex data and alarms and to take safety-critical decisions under the pressure of unexpected and rapidly changing hazardous situations. Thus HMI (Human Machine Interface) has gained greater significance in Occupational health and safety in terms of increasing accidents due to errors.

Human errors because of complex HMI not only results in accidents but also serves as a source for increased mental strain and stress. This Literature review is focused on four main questions: * What are the aspects of HMI design that serve as direct source of human errors? * What is the impact of the human errors due to complex HMI in mental strain and stress of Machine workers in manufacturing industry? * What is the current state of research and development that focuses on reducing the human errors due to complex HMI in manufacturing industry? What is the future direction of research and development on HMI design in relation to reducing human errors in workplace that leads to occupational injuries and illness? 2. Significance of Human Machine Interface in relation to human errors in Occupational Safety and Health.

Increasing importance of Human-machine interface: Consequences of increased automation in workers for workers’ health and safety: • Reduced physical activity leading to psychosocial and musculoskeletal problems. Psychosocial and musculoskeletal problems caused by reduced physical activity, more static postures and higher mental work oad (e. g. when monitoring and controlling); less privacy at work (as technology allows closer and more intrusive supervision); and more decision-making problems.

Increased risk of accidents resulting from human errors, especially in the case of high-risk industries, having the potential for serious consequences beyond the operator to include fellow workers, the wider community and environment. Because of the last 50 years of advancements in manufacturing technology, production processes are using machines which are increasingly powerful in terms of speed, quality, and flexibility.

Linked to increasing mechanization and complexity is a growth in the use of computer-based automated systems in place of human operators to control highly complex technical systems. However, while computer-based systems offer greater reliability and the potential for greater control, they cannot at present match the flexibility of the human operator. It is computers’ inability to cope with unforeseen circumstances that makes the human operator indispensable in complex systems. Particularly at times of failure, systems depend on human operators’ intelligent, context-based thinking.

Technological developments allow a great amount of information to be presented and combined and for many tasks to be carried out simultaneously. Consequently, operator tasks are frequently reduced to those of start up, monitoring and control of processes via digital media. Relatively small errors on the part of the operator have the potential for serious consequences, so additional safety systems are built in, which often result in the operator being overloaded with information.

Conversely, changing a job from one of operating machinery to one of monitoring, control and surveillance, can result in it lacking in content and being regarded as boring and monotonous. The high proportion of employees working with machines or computers means that proper design of the HMI is essential. Poor design of HMI can give rise to occupational diseases, such as stress or musculoskeletal disorders, as well as to occupational accidents. The potential cost to an employer due to reduced productivity, damaged reputation, or users’ dissatisfaction is clear.

Statistics in Manufacturing sector focusing on machine users and type of machines For this section I have planned to collect the following statistical data of following aspects: • Number of Machine dependent employees in all sector and Manufacturing sector. • Machine user statistics of number of users of manual, semi-automatic and automatic process systems in manufacturing sector. • Occupational injuries related to machines in manufacturing sector. • Statistics of machine users exposure to Occupational safety hazard risks in comparison with whole working population.

Machine users health complaints in comparison to total population For collecting all these statistics I have planned of considering US Labor population as the sample data for statistical analysis. OSHA, USA and Bureau of Labor Statistics would be my primary source for collecting information. I would also search literature for any information on statistical inference 3. Human errors and stress: 3. 1. Human errors: There have been numerous attempts at defining human error, and a universally accepted definition does not yet exist; indeed some have even suggested that human errors do not in fact exist or that the concept is outdated.

Putting this contention aside, most definitions focus on actions, unwanted or inappropriate, leading to an undesired outcome, the most widely recognised being that offered by Reason (1990), who formally defines human error as, “a generic term to encompass all those occasions in which a planned sequence of mental or physical activities fails to achieve its intended outcome, and when these failures cannot be attributed to the intervention of some chance agency” Human errors are basically classified into: I.

Mistakes: Mistakes are the errors of interpretation. A mistake can be defined as ‘failure to formulate the right intentions’. The causes may be due to shortcomings of perception, memory and cognition. Tunneling of work memory is attributed as one of primary cause to make mistakes. II. Slips: Slips are errors in which the right intention is incorrectly carried out. ‘Shortcomings of perception’ is one of the mina factors that can cause a slip. III. Lapses: Lapses can be referred as forgetfulness and it represents the failure to carry out an action.

Interruptions are identified as primary causal factor for this type of error. IV. Mode errors: Mode errors are a joint consequence of relatively automated performance or of high workload- when the operator fails to be aware of which mode is in the operation and of improperly conceived system design, in which such mode confusions can have major consequences. 3. 2 Stress impacts as source of human error: In this section of literature I will discuss about how Stress becomes causal factor or a contributory factor for the types of errors discussed above. . Human Machine Interface factors that cause human error: 4. 1 HMI factors causing stress and thereby influencing human error: In context of work-related stress, the primary question is ‘What causes stress in an Advanced Manufacturing environment? ’

The reasons inferred are: • computer users and CNC machine or robot operators, who may have to work on a time sensitive production quota, face heavier workloads, leading to greater mental stress. There is also the psychological pressure resulting from potential to damage expensive AMT equipment or part. The need for increased concentration, and fewer opportunities to utilize personal knowledge and skills, particularly for line workers on the shop floor where machines are automated. • Fear of technological change and reduced job security and job control associated with such change, particularly when automated technologies are involved, have also been identified as sources of stress Influence of HMI in decision making skills of an employee. humans have a strong inclination to fit well-known solution procedures into new problems.

For this reason, changes in work environments can cause accidents when they allow operators to interact with a new device if the latter is erroneously perceived as familiar. Automation should result in better working conditions, however, it can sometimes result in control systems that are more complicated to operate and it can change working methods so that demands increase with regard to stamina, time pressure and the pace of work. As automation reduces the number of operators, those remaining are increasingly isolated and have to act and communicate with the help of the new technology.

Additionally, their workload may increase and the impact of errors is likely to be greater. The changes in how work is organized mean that teamwork loses importance and operators increasingly have to be experts in many different fields and bear more responsibility; this may increase task variety, but can also increase mental work load. 4. 2 Direct impact of Human Machine Interface on human errors: According to Park (1997), there are three main types of causes of human error: 1. Complexity of task (tasks iffer with regard to their demand on mental resources), 2. Situations (some are more likely to lead to errors). The following characteristics increase the probability of human errors: • Inadequate workplace design, • Inadequate design of work equipment and its HMI, • Poor environmental effects, • Inadequate learning and working aids and • Inadequate safety instructions. 3. Preconditions with regard to human capacities. Thus we can see various aspects of Human Machine interface play a major role in control of human error.

I have planned to collect papers which focus on error due to inadequate design of the interface, inadequate knowledge,training on the interface, errors due to continuous change of interface in the industry. 5. Human Machine Interface for mitigating errors and improving work conditions 5. 1 User centered design for reducing errors The focus of the design process is no longer based solely on functional requirements and what is possible technically, but concentrates on the requirements of the intended user.

Users are no longer forced to adapt the way they work to the product; instead it is designed according to their typical work preferences. Use-ware engineering is a multidisciplinary field, which recognises the necessity of bringing together electrical and software engineering as well as industrial psychology, cognitive psychology, and occupational medicine. By using a user-driven and participatory design paradigm, manufacturers take account of user needs from the start of the design process.

This approach uses basic psychological and perceptual principals such as the so-called “Gestalt Laws” in product design and particularly in visual interface design. Gestalt laws/principles Graphical user interfaces often rely on associations between graphical elements like labels, checkboxes and lists. Their positioning is essential for the correct allocation of command descriptions and the buttons that complete it. Gestalt psychology describes principles of perception which determine the way in which objects are perceived.

Gestalt laws or principles o not act in isolation, but rather tend to influence each other, so that the final perception is a combination of all of the Gestalt laws acting together. I have to collect literature paper that explain about each Gestalt principles. 5. 2 Usability engineering Usability engineering applies standards, empirical methods and operational definitions of user requirements in the design and evaluation of products. Use of the resulting products should as intuitive as possible; taking the minimum of time to learn their operation and to accomplish the desired task.

The usability engineering process can be separated into four iterative phases: (1) analysis phase (concerning working system, work, target groups, identification of user demands), (2) concept phase (concept of use with respect to different user target groups and decision on system functionality), (3) development phase (development of prototype and system integration), (4) implementation phase (pilot installation of prototype, industrial engineering). Users are involved in all stages and take an active part in the evaluation processes under the moderation of usability engineers.

The integration of operators in the design process right from the start avoids iterative loops which commonly occur when the testing of HMI is left until the final stages of the process. Involvement of operators in the evaluation process can be achieved through the use of surveys; by direct observation of the user at his workplace; through structured discussions; by participation of the user in design workshops; or through feedback concerning prototypes or products in usability tests. I. Analysis phase: It is important to ensure that the interface is properly adapted to the task and to the conditions in which the task will be performed.

During the analysis phase, the following types of questions must be addressed: Which tasks occur and how often? How are the tasks managed? Who performs them? In what time do they need to be accomplished? What skills are necessary? How are the tasks linked together? What qualifications and qualities do the people performing the tasks have? How do they work together? What hardware and software do they use? What are the working conditions? It is essential to gather information on requirements directly from the operators as they are experts in their work and their ideas may well prevent less than optimal evelopments. II. Concept phase:

Based on the results of the analysis phase, an interdisciplinary team made up of usability experts, industrial engineers, designers and experts involved in organizational development create a concept for the design of the HMI. This phase must consider, for example whether the technical innovations will lead to changes in the existing working process. An important step is the allocation of tasks to humans and to machines, which implies an assessment of the functionalities within the system. The concept must be evaluated and the new system may be adapted . III. Development phase:

Development involves constructing a prototype and evaluating it. This phase gives importance not only to functionality, but also to aesthetic design. Designs of HMI should not only be usable but also permit “joy of use” . IV. Implementation phase: The implementation of the HMI is first of all carried out within a limited set of users and should involve evaluation measures. If amendments are necessary, a loop back to the development phase should follow. If the implementation is judged to be successful, the implementation can be enlarged, but should be accompanied by further evaluation measures.

During the whole implementation process, any worries or fears expressed by users should be taken into account so as to help avoid acceptance problems . 5. 3 Instruction manuals as a source of reducing errors Correct installation and operation of technological products is critical for health and safety. In practice, however, many accidents are caused by faulty installation or operation as a consequence of either not reading or failing to understand the relevant. The importance of providing adequate instructions is reflected in the provisions of the machinery Directive 98/37/EC and ISO standards relating to technical product documentation.

Reinert, Brun & Flaspoler (2007) identified success factors in communicating safety-related information as part of a project to make more users read and understand operating instructions. The study “Complex machinery needs simple explanation” concluded that the best concept for presenting safety-related information consists of a multimedia package for operating instructions comprising a video and poster as well as a paper version of the operating instructions. A video gives elementary information and can raise users’ awareness at the outset using appropriate animation.

Posters are able to explain the key information at a glance and can be placed where the work is being carried out. The main aim of the poster and video is to encourage users to extend their knowledge by referring to the written operating instructions. Several measures were identified that ensure that the information is communicated as effectively as possible: * Visual aids providing an overview of the most important information can integrate simulations, illustrations, comics, photos, tables, colored text, etc. * The text must be readable.

It should be simple, with logical sentences using the active rather than passive form and structured in short informative chapters. * Contents tables and indexes allow the user to find specific information at a glance. * Checklists make text more user-friendly and help guide the users through the necessary steps and let them see whether they have worked adequately. * Instructions for correct operation should be presented sentence by sentence and warnings should be emphasized in the text. * Symbols, terminology and units of measurement should be used consistently (as defined in available standards) and tables should describe them further.

Formulae and concepts should be explained. Glossaries should be used to explain key terminology. * Special attention must be paid to ensure that translations into other languages are adequate. The use of cartoons assists understanding for all readers. * Software help functions and interactive features enable the user to work efficiently with the system. * Quizzes, cross-words, or other games may be used to evaluate the user’ knowledge. Similar success criteria can be found in standards and should be fulfilled when designing operating instructions for products or machines.