micro motion study, memo motion study, cycle graph and chronocycle graph

1. WORK DESIGN AND ERGONOMICS
SEMINAR PRESENTATION
BY: RAHUL SINGH
214218022
TOPICS: Micro-motion Analysis
Memo-motion study
Cycle graph and chronocycle graph
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2. MICRO-MOTION STUDY
 Micro motion study is the technique of recording and analyzing the timing of basic
elements of an operation with the objective of achieving the best method of
performing the operation.
 It provides a technique for recording and timing an activity.
 It consists of taking motion pictures of the operation with a clock in the picture or
with a motion picture camera operating at a constant and low speed.
 The film becomes a permanent record of both method and time and may be re-
examined whenever desired.
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3. PUPOSE OF MICROMOTION STUDY
 Aid in obtaining motion time data for synthetic time standards,
 Permanent record of the method and time employed in the work,
 Aid in studying the relationship of the activities of the operator and the machine,
 Means of timing short cycle operation,
 Aid in studying the activities of two or more persons on group work and
 Research in the field of motion and time study.
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4. PUPOSE OF MICROMOTION STUDY
 The two most important uses of micromotion study are:
1. To assist in finding the most efficient method of doing work.
2. To assist in training individuals to understand the meaning of motion study.
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5. ADVANTAGES OF MICRO-MOTION STUDY
 It provides permanent record of motion study with the help of films.
 A large number of workers can see the procedure at any time even after the
completion of motion study work.
 Differences in the old and new methods can be demonstrated, if both are filmed.
 Films can be demonstrated at any desired speed.
 It gives very accurate time for each motion or operation than that noted by the
stopwatch.
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6. EQUIPMENT FOR MAKING MOTION
PICTURES
 Motion picture camera
 Metal tripod
 Exposure meter
 Photo flood lamps with tripods
 Microchronometer
 Motion picture projector
 Suitable cabinets for film storage
 Rewind, editor, film splicer
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7. PROCEDURE FOR MAKING MOTION PICTURES
 Explain why the picture is being made.
 Locate camera to give best picture of the cycle of operation.
 Locate the photoflood lamps to give adequate intensity of illumination without
deep shadows.
 Place microchronometer so that it will be in the picture and in focus.
 Have sufficient film in the camera for number of cycle to be photographed.
 Measure the distance of the subject from the camera lens and adjust the focus
setting on the camera.
 Turn on the lights, start the microchronometer and make the picture.
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9. FUNDAMENTAL HAND MOTIONS
 Most work is done with the two hands, and all manual work consists of a relatively
few fundamental motions which are performed over and over again.
 Frank B. Gilberth developed certain subdivisions or events common to all kinds of
work and called “therblig” (Gilberth spelled backwards).
 He developed 17 elementary subdivisions of a cycle of motions(“therblig”).
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10. THERBLIGS10

11. THERBLIGS11

12. Simo (Simultaneous Motion) Chart
 SIMO Chart It is a graphic representation of an activity and shows the sequence of
the therbligs or group of therbligs performed by body members of operator.
 It is drawn on a common time scale.
 In other words, it is a two-hand process chart drawn in terms of therbligs and with
a time scale.
 It is generally not possible to time individual therbligs. A certain number of
therbligs may be grouped into an element large enough to be measured.
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13. SIMO Chart Making
 A video film or a motion picture film is shot of the operation as it is carried out by
the operator.
 The film is analyzed frame by frame.
 For the left hand, the sequence of therbligs (or group of therbligs) with their time
values are recorded on the column corresponding to the left hand.
 The symbols/codes are added against the length of column representing the
duration of the group of therbligs.
 The procedure is repeated for the right hand and other body members (if any)
involved in carrying out the operation.
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15. MEMO MOTION STUDY
 It was developed 1946 by Marvin E. Mundel.
 Memo motion or spaced-shot photography is a tool of time and motion study that
analyzes long operations by using a camera.
 It is a form of time lapse photography which records activity by use of cine camera
adopted to take picture at longer intervals than normal.
 Speed is 1-2 frames/sec instead of 24 frames/sec as used in micro-motion study.
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16. MEMO MOTION STUDY
 By employing memo motion study it is possible to record activities
within the working area for long period of time.
 The resulting series of still shots can be analysed and used as a basis
for the construction of appropriate charts and method improvements
such as team operations and several operators on several machines.
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17. MEMOMOTION VS. MICROMOTION STUDIES
 There are many jobs that have activities which does not need to be examined in
fine detail and are still too fast or intricate to be recorded accurately without the
help of a film.
 There are cases where micro-motion study is not justified like smaller production
quantities, job cycle may exceed 4 minute duration etc.
 Memo motion study is much economical than micro-motion study.
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18. Cyclegraph
 A record of path of movements, usually traced by a continuous source of a light on
a photograph.
 The path of movement of a hand, may be recorded on a photograph by putting a
ring carrying small light on worker’s hand.
 A photograph showing movement depicted as continuous pattern of light and is
made by exposing a film or plate for period of the cycle of the activity being
analysed.
 A path of light resembling a white wire is seen. Later it is used with a stereoscopic
camera to show the path in three dimensions.
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19. Cyclegraph
Uses of cyclegraph:
 Unnecessary movements can be identified.
 Improving the motion pattern.
 Training purposes in which two cycle graphs may be shown with one indicating a
better motion pattern than the other.
Disadvantages of cyclegraph:
 Does not indicate direction of the motion.
 Does not show acceleration, deceleration or uniform speed in motion.
 Complex processes may result in highly entangled cyclegraph.
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20. Cyclegraph20

21. Chronocycle graph
 The chronocycle graph is similar to the cycle graph, but the power supply to the
bulb is interrupted regularly by using an electric circuit.
 The resulting picture instead of showing continuous line of motion pattern, shows
short dashes of line spaced in proportion to the speed of the body member
photographed.
 The jumbling of dots at one point would indicate fumbling or hesitation of the
body member. A chronocycle graph can thus be used to study the motion pattern
as well as to compute velocity, acceleration and retardation experienced by the
body member at different locations.
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22. Chronocycle graph
Old method New method
fig. chronocycle graph of a process on assembly line

23. Chronocycle graph
Old method New method
fig. chronocycle graph of a process on assembly line

24. Chronocycle graph
Fig:chronocycle graphsOld method New method

25. Chronocycle graph25

26. Chronocycle graph26

27. QUESTIONS?
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28. THANK YOU!
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