22 COMPONENTS OF WORK, WORK ANALYSIS USING DIFFERENT TECHNIQUES-COMPONENTS OF WORKER INPUT
Sarasvathi. V
Introduction:
Work well done is satisfying and rewarding. By and large household tasks are tedious, monotonous and time consuming, requiring varied skills. Through time and motion studies, ways and means have been found of, make each job simple, easier and more satisfying. There are various work simplification techniques for analysis of work which have proved useful and can be adapted by the home makers in their homes. These techniques are useful in making time and motion studies of the work that is being done, analyzing the work methods, developing the easiest and most effective way to do the task, and putting the new method into use. In recent years work simplification techniques have been used by research workers in home economics. Efficient kitchen arrangements, tools, equipment storage facilities, and correct heights for work surfaces, chain and stools have also been studied. These studies suggest many methods of simplifying homemaking tasks, which may be used or adapted by homemakers in their own homes. They show how motion and time studies may be applied to any work problem in the home. Trying out new work patterns and adjusting them to meet new situations add interest to the work.
Components of work
If mechanics is defined as the science dealing with force and motion, then body mechanics is, of course, a science dealing with body forces and motions. The term body mechanics is itself a popularization of kinesiology “scientific study of movements of the human body states Duvall. Body mechanics is of interest because of a desire to keep the home maker’s costs of work at a minimum. The physical costs of work can be too high in fatigue even for light work if the natural structure and functions of the body are disregarded during work performance. An untrained worker often will work against her body rather than let her body work for her. The physical cost of work can then be out of proportion to the amount of work in the technical sense of foot-pounds, in energy expended, or in the discomfort strain felt.
Body mechanics, although concerned chiefly with energy setting includes feeling of comfort and discomfort associated contracting muscles and skeleton. Among its major principles are
(1) Keeping the body parts in alignment,
(2) Considering the center of gravity, of both of the body and article that is been handled.
(3) Using muscles effectively
(4) Taking advantage of momentum,
(5) Rhythm in movements.
Other principles includes
- Remain close to the object
- Use short lever arms for better control & efficiency (with less strain)
- Maintain the COG close to the object’s (or patient’s) COG
- Widen the BOS (Base of Support) and position the feet according to the direction of movement one will use to perform the activity
- Use the largest & strongest muscles of one’s arms, legs and trunk
- Avoid twisting the body when one lifts
- When possible, push, pull, roll, or slide an object rather than lifting it
When any part gets out of line, muscular effort is required to maintain body balance in addition to whatever work the body is doing. Strains may also result. When there is a problem of maintaining balance, a border base of support is necessary. The feet may be wide apart or parallel with one in advance of the other. Thus while the various homemaking activities require different combinations of effort, most tasks require mental, visual, manual, and torsal effort of some kind and a large number also require pedal effort.
The human energy required for the performance of any task is made up of several different parts. A certain amount of energy is needed for the maintenance of muscular tension and for the natural body processes such as respiration, circulation, secretion, and excretion. This is known as resting metabolism. In addition there is the energy used in moving about and in the actual doing of the task.
Time Study
•Time study is a tried and tested method of work measurement for setting basic time and hence standard times for carrying out specified work.
•The aim of time study is to establish a time for a qualified worker to perform specified work under stated conditions and at a defined rate of working.
• This is achieved by a qualified practitioner observing the work, recording what is and simultaneously rating (assessing) the pacea of working.
Motion study is the systematic recording and critical examination of existing and proposed ways of doing work, as a means of developing and applying easier and more effective methods and reducing cost.
Aims
1. To eliminate wastage of time and labour.
2. To reduce fatigue of work by eliminating unnecessary movements.
3. To find best way of doing job and obtain grater job satisfaction.
4. To utilize effectively men, machine and material.
5. To improve the factory and offices layout and also design of plant equipment and building.
6. To standardize the method, obtained after conducting Motion study.
7. To train the workers as per standardized method.
8. To provide better working conditions and environment
Motion Study is designed to determine the best way to complete a repetitive job.Time Study measures how long it takes an average worker to complete a task at a normal pace.
A time and motion study (or time-motion study) is a business efficiency technique combining the Time Study work of Frederick Winslow Taylor with the Motion Study work of Frank Lillian Gilbreth.Time and motion study analysis of the operations required to produce a manufactured article in a factory, with the aim of increasing efficiency. Each operation is studied minutely and analyzed in order to eliminate unnecessary motions and thus reduce production time and raise output, which increases productivity. The first effort time study was made by F. W. Taylor in 1880s. Early in the 20th cent., Frank and Lillian Gilbreth developed a more systematic and sophisticated method of time and motion study for industry, taking into account the limits of human physical and mental capacity and the importance of a good physical environment. Time and motion study have to be used together in order to achieve rational and reasonable results. It is particularly important that effort be applied in motion study to ensure equitable results when time study is used. Motion study can be considered the foundation for time study. The time study measures the time required to perform a given task in accordance with a specified method and is valid only so long as the method is continued. Once a new work method is developed, the time study must be changed to agree with the new method.
Purpose of time and motion study
• The main objective of a time and motion study is to determine reliable time standards for the efficient and effective management of operations.
• Through the establishment of reliable and accurate time standards, companies can better define their capacity or output, thus increasing the efficiency of equipment and obtaining optimum utilization of the workforce.
• The objective of the Time and Motion Study is to determine a ‘normal’ or average time for a job, by using observers to record exactly how much time is being devoted to each task.
Frank Bunker Gilbreth, Sr.
- He was an early advocate of scientific management and a pioneer of motion study.
- The Gilbreths, sought to make processes more efficient by reducing the motions involved.
- Gilbreth named the motions therbligs, “Gilbreth” spelled backwards with the “th” transposed. He used a motion picture camera that was calibrated in fractions of minutes to time.
- A time and motion study would be used to reduce the number of motions in performing a task in order to increase productivity without sacrificing quality.He experimented on bricklaying, he reduced the numbers of motion from 18 to 5.
- A therblig is the name for one of a set of fundamental motions required for a worker to perform a manual operation or task.
• Search: the time and attention required varies with the number of dimensions in which the search is performed.
Gilbreths reducing Search was by arranging tools and parts in a physical sequence of use through the Packet Principle.
• Find: Find can be considered a demarcation line, denoting the end of the Search cycle.
• Select: the retention of an object after it has been grasped, [with] no movement of the object taking place.
• a Grasp, of an object, occurring in one hand, while the other hand performs a Use or Assemble function.
• Transport Loaded: begins after Grasp where the hand is doing “work” by moving the weight of an object, and ends when just before the Release Load, Use or Assemble.
• Transport Empty: This is the motion of moving the unloaded hand from the point of Release Load, to the next function within the sequence.
• Position: motion is the act of placing the object in the proper orientation for Use.
• Assemble: starts when two or more parts are placed together and ends when either the assembled object is Transport Loaded or when the hand reaches for another part
• Use: Use is when an object is being operated as it was intended, and typically denotes a tool
• Disassemble: This motion is essentially the opposite of Assemble.it could also be the act of removing a part from a jig or clamp, which held the part during the Use or Assemble motion.
• Inspect: the act of comparing the object with a predetermined standard.
• Pre-Position: This is the motion of replacing an item in the proper orientation for it’s next Use.
• Release Load: This motion involves releasing the object when it reaches its destination.
• Unavoidable Delay: measured from the point where a hand is inactive to the point where it becomes active again.
• Avoidable Delay: This counterpart to Unavoidable Delay, involves inactive time the worker encounters over which he/she has control.
Inspection, body parts
• Plan: mental function, which may occur before Assemble or prior to Inspection, noting which flaws to look for.
• Rest to overcome Fatigue: This Therblig is actually a lack of motion and is only found where the rest is prescribed by the job or taken by the worker
PROCEDURE FOR MOTION STUDY
1. Select and define:-The work to studied is selected .Define the objective to be achieved.
2. Records:-The facts about existing methods should be clearly recorded by using following recording technique.
(a).Charts:
(i) Outline process chart
(ii) Flow process chart
(iii) Two hand process chart
(iv) Multple activity chart
(v) Travel chart
(b) Diagrams: (i)Flow diagram (ii)String diagram (iii)Cycle graph (iv)Chronograph
(c).Motion and film analysis:
(i) SIMO Chart
(ii) PMTS
(d).Layout Models:
(i) Two dimensional model
(ii) Three dimensional model
3.Critical examination :-Question each detail of the job.
4. Develop a New method:-After examining all the facts and analysis of results, a better way of doing an activity can be developed.
5. Install the new method:-After having developed the method, this is required to install. The new method must be got approved from supervisors, workers and management. Then worker must be trained to work according to new product.
6. Maintain new method:-Once the new method has been installed, it should be maintained in its specified from and worker should not be allowed to slip back to old method or introduced any other unauthorised changes.
The Principles of Motion Economy
Set of rules were designed by Gilberthinorder to develop better methods.
A better method of doing a job is one which consumes minimum of time and energy in performing limb (hand, foot, leg, arm etc.) motions in order to complete the task and this is possible only, by economizing the use of motion.
The rules of human motion as presented by Gilberth were rearranged and amplified by
Barnes, Lowry, Maynard and others.
The various rules are as follows
- Rules concerning human body
- Rules concerning work place and material handling Rules concerning tools and equipments.
Rules Concerning Human Body
• The two hands should begin and complete their movement at the same time .
• The two hands should not be idle at the same time except during period of rest.
• Motion of the arms should be symmetrical, opposite directions, simultaneous.
• Motions should be simple and involve minimum number of limbs(of course depending upon the type of work).
• It is very desirable for a worker to employ momentum to assist himself where the same (momentum)is not to be overcome.
• Motion should be smooth and continuous; they should not involve frequent stops and directional changes.
• Ballistic movements (i.e., free swinging) are faster, easier and more accurate than restricted or controlled movements.
• A worker may use mechanical aids to assist him to overcome muscular effort.
• Work movements should be rhythmical and automatic, if possible.
Rules concerning work place and material handling
•There should be a definite, fixed and easily accessible location for materials and tools.
•Materials, tools and other mechanical devices should be kept close to the work place.
•Gravity feed, bins and containers should be used to deliver the materials as close to the point of use as possible.
•Tools and materials should be located within the maximum working area and near to work place.
•Materials and tools should be arranged to permit the best sequence of motion.
•Good illumination is necessary for proper seeing, fast operating and reducing accident.
•In order to reduce fatigue, the seating arrangements of the workers sholdbe comfortable and adjustable.
All heavy parts should be lifted by mechanical devices
Rules concerning tools and equipments
• Two or more tools should be combined wherever possible.
• Preferably, tools and materials should be replaced and located near the working place. It saves time or otherwise wasted in searching and bringing the tools for doing a job.
• There should be maximum surface contact in-between the tool (handle) and the hand. It helps proper application of hand force and minimizes fatigue.
Work simplification is defined as the use of equipment, ergonomics, functional planning and behavior modification to reduce the physical and psychological stresses on the body of activities at home or work. By reducing the physical demands on the body during tasks acts to preserve the joints and reduce the risk of injury or re-injury. (Glanze, Anderson & Anderson 1990).
Simpler Techniques of Work Simplification
For purposes of influencing homemakers toward becoming more motion – minded, the elaborate techniques of industry are out of place .
Popularized forms of research films are, of course, good for arousing interest, but the detailed analysis of films is impractical for home makers.
At a more practical level, certain simpler techniques of study are possible.
At the turn of the 20th century when industry became interested in the efficiency of labor, the young wives of two efficiency engineers brought the idea of improving work methods into home under various names, the last of which was work simplification.
The term work simplification as used in the home is of a more far-reaching nature than in industry and may even include omitting a task in its entirely. For example, a bakery might apply work-simplification techniques to the method of making apple pies, but would not question making them as long as they have profitable market. A home maker might similarly simplify her method of making apple pie, but she might further simplify the task of preparing a dessert by making no apple pie but substituting baked apples. This latter in a fundamental sense is also work simplification
Work simplification implies a conscious effort to seek out the easiest, quickest and simple’s method of doing a task. It implies the use of least time, effort and energy in carrying out a task to completion. This could be achieved either by the use of labour saving equipment and devices such as mixers, grinders cookers, washing machines vacuum cleaners, dish washers etc. or by simplifying the technique of doing the work. Research by the way, Time and Motion Studies have revealed that a task could be made less time and energy consuming through the adoption of certain techniques and planning. Mundal has listed five levels by which work could be simplified:
1. Changes in the body position and motion.
2. Changes in the tools, working arrangements and equipments
3. Changes in the production sequence
4. Changes in the finished product
5. Change in the raw materials
Techniques of Work Simplification
Attention was first focused on work simplification through research carried on in the industrial field. Motion and time studies showed that improvements in methods of work not only eliminated useless motions but also saved the time and energy of the worker. Work simplification research consists of making motion and time studies of the work as it is being done; analyzing the work methods; developing the easiest and most effective way to do the task; and putting the new method into use. The three techniques used for motion and time studies are: The process chart, the operation chart and micro motion film analysis.
Process Chart: The process chart is a step-by-step description of the method used in doing the task. It shows the flows of movement of work and the worker and is most helpful in calling attention to unnecessary steps and motion. It is an overall investigation. It requires at least two people to make a process chart, one to do the task and at least one other to observe and record. The time is relatively unimportant, as the focus is upon the flow of work. The chart helps to visualize the sequence of an activity. For charting home tasks, the worker is followed throughout. It is customary, in this method of research, to perform and chart the same task in an original and then in a revised way. The count of symbols of the original way often indicates at a glance where improvement may be made. Different motions used to handle the work are observed and recorded. The analysis at the end of the work points out extra motions out extra motions used which can be eliminated to improve the method of work.
Process chart showing setting a table
Operation Chart:
The operation chart is used in making a more detailed study of some particular part of the process. The operation chart is similar to a process chart, expect that it picks up one particularstep in a whole process and breaks it down into the work of each hand, shown parallel columns. In this chart the movements are broken down into the activities of both the right and left hand. The finer analysis shows where unnecessary motions are being made and where delays occur in work. Both process chart and operation charts are useful motion and time-study techniques. They require no special equipment and their use produces astonishing result. In this chart the movements are broken down into the activities of both the right and left hand. The finer analysis shows where unnecessary motions are being made and where delays occur in work. Both process charts and operation charts are useful motion- and time-study techniques. They require no special equipment and their use produces astonishing results. Micro motion film analysis is primarily a research technique and applies best to tasks that can be easily filmed. Motion pictures of tasks done under normal conditions make a permanent record. It can be analysed and charted and how the work of the hands or other parts of the body is used in the operation. By means of a timing device, the time of each movement of the worker can be accurately recorded. Process chars drawn up a show the flow of movement of the worker and the work, have helped in the elimination of certain unnecessary motions. Operation charts on the other hand have contributed greatly in reduction of hand movements in any particular task. These helps to make the worker more conscious of his movements. Thus, allowing for better planning and elimination of his movements, work time is reduced and energy conserved by fewer and effective motions.
Uses of Operation Chart
- It helps us to be more motion and time conscious. It helps to sharpen ones power of observation.
- To record, in sequence, the elemental movements of the hands of a worker at a given station
- Analysis of chart gives a basis for reducing transportation to the lowest degree possible
Motion Economy
Motion Economy
Both hands should do useful work at the same time, starting and stopping together
Hands should be freed of any work that could be done by another part of thebody
Arm motions should be simultaneous and in opposite and symmetrical directions
Use the fewest, shortest, simplest motion
Eliminate body motion that is unproductive
Eliminate unnecessary walking, reaching, stretching and bending
Use the available equipment that is best for the job
Food, utensils and equipment should be located close to the point of use
Arrange work, tools and materials in sequence of use
Combine operations and eliminate all unnecessary parts of the job
Micro-Motion Film Analysis:
Micro-motion film analysis is primarily a research technique and applies best to tasks that can be easily be filmed. Motion pictures of tasks done under normal conditions make a permanent record that can be analyzed and charted to show the work of the hands or other parts of the body used in the operations. By means of timing device, the time of each movement of the worker can be accurately recorded.
The cycle graph, a photographic device, is also used to study types of motions used in performing tasks. When this is attached to some portion of the body, such as the hand when ironing is being done, it registers the pathway of light projected by a small electric bulb. The resulting record shows whether the move- are smooth and rhythmic or This is an effective way to learn how motions may be reduced and how methods of work may be improved in doing a task. One of the newest devices now being tested is the chronocyclegraph. By using small lights on the middle finger of each hand,patters of simple and intricate tasks can by photographed and recorded on a film
Pathway Chart:
The pathway chart is a simple device for making a motion and time study in the home. A floor plan drawn to scale and fastened to a drawing board or wallboard, pins and thread are all that are needed to make such a study. The pathway chart focuses the analysis on overall amount of travel and retracing of steps. The pin and string method of making a pathway chart suggested by Mrs.Gilbreth.
Applications of Performance Improvement
- Eliminate unnecessary operations, delays and moves
- Combine operations
- Change sequence of operations
- Reorganize equipment
- Improvements in design of equipment
- Reduction in movement of materials and equipment
- Use of different products
Conclusion
Time and work-reducing ideas-work simplification and motion-mindedness-may be used by everyone. Work simplification is the conscious seeking of the simplest, easiest, and quickest method of doing work. Motion-mindedness is an awareness of the motions involved in doing a task and an interest in possible ways of reducing them.The Busy Homemaker who wants to free more energy for certain activities, the employed homemaker who needs to lighten her home workload, and the disabled homemaker who must learn to conserve her energy can use the principles and techniques of work simplification studies of homemaking tasks indicate that change and improvement in work methods are possible in every home. It is the responsibility of employees to use good body mechanics and maintain healthy life-style habits to help prevent injury.
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