PREDETERMINED MOTION TIME SYSTEMS (PMTS) ANALISA DAN PENGUKURAN KERJA

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1 PREDETERMINED MOTION TIME SYSTEMS (PMTS) ANALISA DAN PENGUKURAN KERJA 13 Debrina Puspita Andriani debrina@ub.ac.id Blog :

2 METODE PENGUKURAN [WAKTU] KERJA PENGUKURAN [WAKTU] KERJA DIRECT INDIRECT STOPWATCH STANDARD DATA WORK SAMPLING PMTS Regression Analysis 2

3 An alternative time study that does not require performance rating. A database of basic motion elements and their associated normal time values, together with procedures for applying the data to analyze manual tasks and establish standard times for the tasks. PMTS defined

4 Basic motions include: Reach Grasp Move Release A set of tables that listing time values that corresponds to basic motion elements, the lowest level in hierarchy of manual work activity. PMTS defined

5 Frank B. Gilberth- 17 therbligs Asa B. Segur Mo;on Time Analysis (MTA) - the first commercial PMT system (1922) and base on Gilberth s 17 therbligs H. Quick Work-factor system ( ): cogni;ve work involved Harold B. Maynard Methods- Time Measurement (MTM) (1948): very successful and widely used G.Chris Hyde- Modular Arrangement of Predetermined Time Standards (MODAPTS) 1966 Kjell B. Zandin- Maynard OperaGons Sequence Technique (MOST)-(1970s) Computeriza;on of systems as commercial products 5 Historical Notes

6 Maynard Operation Sequence Time (MOST) Pengukuran Waktu Metode (MTM) Analisa waktu gerakan (MTA) Terdiri atas : Waktu Gerakan Baku (MTS) Waktu Gerakan Dimensi (DMT) Data Waktu Gerakan Faktor Kerja (WF) 6

7 PMTS Procedure 1. Synthesize/Analyze method that would be used to perform the task Ê The method is described in terms of basic motion elements 2. Retrieve normal time values for each motion element Ê Sum the element times to determine the task normal time 3. Evaluate method to make improvements by Ê Ê Ê eliminating motions reducing distances using both hands simultaneously etc. 4. Apply allowances to determine standard time 7

8 PMTS Levels and Generations First-level PMTS use the basic motion elements Reach, grasp, and move used separately to define the task Higher-level PMTS combine several motion elements into motion aggregates Reach and grasp combined into one element called get First-level systems were chronologically the first to be developed and are called first generation PMTS 8

9 Comparisons First-level PMTS Most accurate High application speed ratio Most suited to highly repetitive short cycles Basic motion elements Very detailed Highest flexibility Detailed M T M Higher-level PMTS Less accurate Less time to set standards Longer cycle times feasible Motion aggregates Less detailed Less flexible Simplified and condensed M O S T 9

10 METHODS TIME MEASUREMENT (MTM)

11 Methods-Time Measurement (MTM) ü Procedure which analyzes any manual operation or method into the basic motions required to perform it and assigns to each motion a predetermined time standard which is determined by the nature of the motion and the conditions under which it is made. ü Time units are TMUs 1 TMU = 10-6 hr = min = sec 1 sec = 27.8 TMU ü MTM is a family of products available through the MTM Association ( 11

12 MTM-1 Job Level Task Level Work Element Level Basic Motion Level ACTIVITY HIERARCHY OF WORK 12

13 M T M 1 (1948) Operates at the basic motion element level in our pyramidal structure of work Most MTM-1 basic motions involve hand and arm movements Also includes elements for eye, leg, foot, and body actions Many of the basic motion elements correspond to the original Therbligs developed by Frank Gilbreth More appropriate for tasks that are highly repetitive and cycle times are less than 1 min 13

14 Ê Reach (R) Ê Perpindahan tangan atau jari ke tujuan - dipengaruhi oleh panjang gerak dan jenis jangkauan. Ê Move (M) Ê Transportasi objek ke tujuan - dipengaruhi oleh panjang gerakan, berat benda dan jenis gerak. Ê Grasp (G) Ê Pengamanan dengan kontrol yang cukup pada satu atau lebih objek dengan jari atau tangan untuk mengizinkan kinerja gerakan yang diperlukan berikutnya - dipengaruhi oleh bentuk dan lokasi objek. Basic Elements Ê Position (P) Ê Pelurusan, orientasi, dan penglibatan obyek dengan obyek lain (bila hanya gerakan kecil diperlukan) - dipengaruhi oleh kemudahan penanganan, simetri, dan jumlah tekanan yang dibutuhkan untuk penyisipan. 14

15 Ê Release (RL) Ê Melepaskan kontrol dari sebuah objek dengan jari atau tangan. Ê Disengage (D) Ê Istirahat kontak antara satu objek dengan yang lain - dipengaruhi oleh jumlah usaha yang diperlukan. Ê Turn (T) Ê Gerak yang digunakan untuk mengubah keadaan tangan, kosong atau dimuat, dengan gerakan yang tangan berputar, pergelangan tangan, dan lengan bawah pada sumbu panjang lengan bawah - dipengaruhi oleh tingkat rotasi dan dengan berat benda. Basic Elements Ê Apply Pressure (AP) 15

16 Ê Eye Travel (ET) Ê Dianggap hanya ketika mata harus mengarahkan tangan atau gerakan tubuh (termasuk fokus mata dan mata waktu travel) - dipengaruhi oleh jarak antara titik-titik perjalanan dan jarak antara mata ke garis perjalanan. Ê Body of Leg and Foot Motion (BMF) Ê Gerakan lain yang berhubungan dengan tubuh dan kaki (berjalan, berdiri, membungkuk, dll). Basic Elements 16

17 Example : R10C = 12.9 TMUs 17

18 Example : G1C3 = 10.8 TMUs 18

19 Example : M6B

20 Motion Element : Move (M) Normal Time = constant + (dynamic * time in TMU) Example : M6B12 à Normal Time = (1.11 * 8.9) = 13.8 TMUs 20

21 Example : P3NSD = 53.4 TMUs Round peg in a round hole: S(ymmetrical) Key inserted in a lock: N(on)S(ymmetrical) 21

22 Example : RL1 = 2 TMUs Example : D2D = 11.8 TMUs 22

23 Example : T30L = 8.4 TMUs Example : APB = 16.2 TMUs 23

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26 Notasi Gerakan Notasi umum untuk setiap gerakan pada MTM adalah: a b c dimana : a : gerakan dasar yang bekerja b : jarak yang ditempuh c : kelas dari gerak dasar yang bersangkutan 26

27 Notasi Gerakan Contoh : R 16 A = Reach, jarak 16 inches, description A G 1 A = Grasp, description 1A 27

28 MTM-2 (1965) Secondlevel PMTS in which basic motion elements are combined into motion aggregates (11 motions) GET combines Reach and Grasp PUT combines Move and Position For tasks that are not highly repetitive and cycle times are greater than 1 min MTM-3 (1970) Third-level PMTS which has four motion categories Handle Transport Step and foot motions Bend and arise Other MTM Systems MTM-V : Metal cutting operations MTM-C : clerical work 28

29 MTM Software ( 29

30 MAYNARD OPERATION SEQUENCE TECHNIQUE (MOST)

31 M O S T MOST is a high-level PMTS based on MTM o Same time units as MTM: TMU o Developed around 1967 under the direction of Kjell Zandin. o MOST is a product of H.B. Maynard and Company (an educational and consulting firm), Pittsburgh, Pennsylvania ( 31

32 MOST Job Level Task Level Work Element Level Basic Motion Level ACTIVITY HIERARCHY OF WORK 32

33 Ê MOST lebih cepat karena lebih sederhana, dengan membagi aktivitas kedalam pekerjaan yang umum dan tidak terlalu mendetail. Ê Dokumentasi yang diperlukan lebih sedikit, jadi juga menghemat biaya. Ê Hasil pengukuran sangat valid dan dapat diterima secara statistik Kelebihan MOST 33

34 Basic MOST Focused on work involving the movement of objects (e.g., parts, tools) from one location to another in the workplace Uses motion aggregates Called activity sequence models Three activity sequence models: 1. General move object moved freely in space 2. Controlled move object remains in contact with a surface 3. Tool use use of hand tools (e.g., hammer, screwdriver) 34

35 Activity Sequence Model Subactivities General Move ABG ABP A A - Action Distances B - Body Motion G - Gain Control P - Place Controlled Move ABG MXI A M - Move controlled X - Process time I - Align Tool Use ABG ABP * ABPA *F Fasten *L Loosen *C Cut *S Surface treat *R Record *M - Measure Basic MOST 35

36 1. General Move Consists of sequence model parameters, which correspond roughly to basic motion elements. Sequence model parameters for General Move: A : Action distance (move hands or feet) horizontal body motions B : Body motion (sit, stand up) vertical body motions G : Gain control (closely related to grasp) P : Placement (e.g., position, lay aside, orient) 36

37 1. General Move Standard sequence in General Move: A B G A B P A get move return ABG : to get an object; ABP : to move the object to a new location; A : return to original position 37

38 1 Index = 10 TMU 38

39 1. General Move Develop the activity sequence model and determine the normal time for the following work activity: A worker walks 5 steps, picks up a small part from the floor, returns to his original position, and places the part on his worktable. Solution : A 10 B 6 G 1 A 10 B 0 P 1 A 0 where A 10 =walk 5 steps; B 6 =bend and arise; G 1 =gain control of small part; A 10 =return back; B 0 =no body motion; P 1= lay aside part on table; A 0 =no motion The sum of index values: 28. Normal time: 10*28=280 TMUs 39

40 2. Controlled Move Used when an object is moved through a path that is somehow constrained. M : Move, controlled X : Process time I : Align 40

41 2. Controlled Move Standard sequence in Controlled Move: A B G M X I A get move return ABG : to get an object; MXI : to move the object followed by a process time and alignment, A : to return 41

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43 2. Controlled move Develop the activity sequence model and determine the normal time for the following work activity: A worker takes 2 steps, grasp the waistlevel feed lever on the lathe, pulls up the lever approximately 15 cm to engage the feed. Process time to turn the part is 25 sec Solution: 25 sec.s = 25 * 2.78 = 69.5 TMU = 7 index A 3 B 0 G 1 M 1 X 7 I 0 A 0 where A 3 =walk 2 steps; B 0 =no body motion; G 1 =gain control of lever; M 1 =pull the lever up 15 cm: X 70 =process time of ; I 0 =no alignment; A 0 =no motion The sum of index values: 12. Normal time: 10*12=120 TMUs

44 3. Tool use Bagian yang memakai alat diisi dengan salah satu parameter: F : fasten (mengencangkan) L : loosen (mengendurkan) C : cut S : surface treat (misal: Ampelas) M : measure R : record T : think 44

45 3. Tool use Only one is used in a sequence: ABG ABP * ABP A ABG: to get the tool ABP: put the tool in the position *: tool use code ABP: put the tool aside A: return 45

46 Maxi MOST for work cycles performed fewer than 150 times per week and there are variations in the cycle Can be applied to tasks of several hours Clerical MOST similar to Basic MOST but designed for clerical tasks Mini MOST for highly repetitive work cycles performed more than 1500 times per week MOST for Windows Computerized technique that allows user to apply Basic MOST, Maxi MOST, or Mini MOST to the task Other Versions of MOST 46

47 Knowing exactly what you want to do, and then seeing that they do it the best and cheapest way. - Frederick W. Taylor-! 47