By group 5Angelica AgacitaFruilene Isabel PanesLanmark MabasaIan Nilo Andales
At the end of the activity the students are expectedto: Apply the concept of hand and motion economy aswell as the use of therbligs in the study Analyze every step in the ship assembly process Make an effective data sheet Make use of stopwatch time study
Make a data sheet containing left and right handchart, therbligs, and time of assembly including thedescriptions of every motion of the worker. Prepare the parts of toy ship to be assembled. Assign a worker to perform the experiment (thetoy assembly).
While the worker performs, do the time study andrecord the motions of the worker. Fill the data sheet with the information gathered. Compute the units that a worker can finish on aday(8hrs). Publish the results.
In using the left-right hand chart, it is very important totake note every motion involve and take considerationsthat these are operations. But there are some activitiesthat are not taken to account into the chart because thesetypes of operations might not be done by the sameoperator(Aft, 2000).
There are different definitions of left-hand/right hand chart given byvarieties of authors in Methods Engineering. This chart is one onwhich the motions made by one hand in relation to those made bythe other hand are recorded using standard process chart symbols(Aft, 2000). Left-hand/right-hand chart is for one operator only, treating eachhand as an activity; each hand’s activity is broken into elements andis plotted to the column adjacent to the other hand (Meyers, 2002).The principal purpose of the chart is to assist in finding a better wayof performing the task (Barnes).
Throughout the operations taken, the charts or set of data taken canbe used to improve productivity. There are factors or classificationas well, to be considered in the process of improving theproductivity of the worker. These are the use of the human body,workplace arrangement and the design of tools and equipment.The human body deals with the effectively use of the physicalattributes when it is required in a production situation. The secondfactor deals with the most effective layout of the working area.Lastly, the third classification deals with the appropriate design ofequipment for the ease of operation by the operator.
An ideal worker in the workstation must be productive as tokeeping a sufficient amount of work. There must not be anidle time at all and everything has to be balance, the startingand stopping times of the hands (based from Principle 2 ofmotion economy principles). The motion of the hands has tobe fast and follows smoothly to the rhythm of the prescribedmethod. The more identifiable the rhythm is, the easier the jobwould be in harnessing the feeling and make the job moreproductive.
Stopwatch time study was the first technique used to setengineering time standards. However, Meyers (2002)stressed that stopwatch time study may not be the besttechnique for setting a particular time standards, but it maybe the “agreed-on method” to be used.
In measuring the time standard, you must take the step-by-step procedure.1. select the job to study2. Collect information about the job3. Divide the job into elements4. Do the actual time study5. Extend the time study6. Determine the number of cycles to be timed7. Rate, level and normalize the operator’s performance8. Apply allowances9. Check for logic10. Publish the time standard
One important attributes that a time studytechnician must have is the positive attitudetowards using stopwatch, making allowances,rating the performance, communicating to theoperator and setting the time standards.
element 1 2 3 4 5 6 7 8 9 10Inserttopbase to2ndbase2.00 2.05 1.72 1.66 1.72 1.86 1.61 1.67 1.60 1.64Inserttop-2ndbase tothe 1stbase2.10 2.59 1.92 1.99 1.90 2.02 2.04 1.83 2.58 1.33*the time is in sec
FATIGUE 480 seconds or 8 minsPERSONAL 480 seconds or 8 minsDELAY 480 seconds or 8 minsALLOWANCES IN % = (24 min / 480) x 100 % = 5 %
TOTAL NORMAL TIME = 2.09 + 2. 42 = 4.5 seconds
Total Mean (X)Range(R)R/XNormalTimeTotalNormalTimeStandardTimeOutputPer Day17.53 1.753 .45 .28 2.094.5 4.746076Units20.30 2.03 .76 .37 2.42
Simo chartLEFT THERBLIGS THERBLIGS RIGHTDESCRIPTION DESCRIPTIONreach for the second base TE TE reach for the top basegrasp the second base G G grasp the top basecarry the second base TL TL carry the top baseassemble the 2nd base to the top base A A assemble the top base second basereach for the first base TEHhold the assembled partsgrasp the first base Gcarry the first base TLassemble the first base to the assembled parts A A assemble the parts
reach for the second base TE TL Carry the toy to the bingrasp the second base G RL Drop the toy shipcarry the second base TL TE Reach for the basehold the 2nd base HG Grasp the top baseTL Carry the top baseAssemble the second base to the top base A Aassemble the top base to the secondbaseReach for the first base TEH Hold the assembled partsGrasp the first base GCarry the first base TLAssemble the first base to the assembled parts A A Assemble the parts
reach for the second base TE TL Carry the toy to the bingrasp the second base G RL Drop the toy shipcarry the second base TL TE Reach for the basehold the second base HG Grasp the top baseTL Carry the top baseAssemble the second base to the top base A Aassemble the top base to the secondbaseReach for the first base TEH Hold the assembled partsGrasp the first base GCarry the first base TLAssemble the first base to the assembled parts A A Assemble the parts
Therbligs Left Hand Right HandTE 6 3G 6 3TL 6 5A 6 6H 2 3
PRINCIPLE 3: motion of the arms should be made inopposite and symmetrical directions and should bemade simultaneously., The two hands were able to complete the task andits use were made effectively. It can be seen fromthe simo chart that the hands were functioningand the task were divided.
PRINCIPLE 8: work should be arranged to permit easy andnatural rhythm wherever possible.PRINCIPLE 9: eye fixations should be as few and as closetogether as possible. The arrangement of the parts were made according to thedistribution of the task for the hands. The parts werelocated in away that the operator can reach withoutstretching or causing so much effort. With these the eyefixations are few. Considering that there are only threeparts to be assembled and is easy to manage.
Principle 13:Drop deliveries should be usedwhenever possible.The bin was provided for the finishedproducts in order to separate it from theother parts. One advantage of the dropdelivery is to protect the finished productfrom damage.
Principle 16: The height of the workplace and the chairshould preferably be arranged so that the alternatesitting and standing are easily possible. The chair and the working table were provided ina way that the worker is comfortable to use it. Theheight does not permit the operator to work in arestricted motions.
Principle 18: the hands should not be relieved of all worksthat can be done advantageously by a jig, a fixture or afoot-operated device. The hand did most of the tasks and there were noavailable machineries or fixtures or even a jig thatcould help the operator. In a demanding point ofwork, the worker will accumulate psychological andphysical stress
Principle 1: Two hands should begin as well as complete their motionsat the same time. The two hand were able to begin at the same time but were notable to complete the motions significantly.Principle 2: two hands should not be idle at the same time exceptduring rest periods. It can be seen from the simo chart that there was long holding ofthe parts. Although, the hands were not idle but hold is anineffective therblig that needs to be eliminated.
Time study is now being used by the companies toestablish a time standard. By this, the company will knowthe number of units that can be produced by a worker in acertain period of time. Also, it is used to identify theineffective time that must be eliminated duringproduction. The time study is used to improve themethods or procedures adopted in performance of variousjobs. This is very important for the company to improvetheir production and increase their profit.
It is also an important reminder that spendingsignificant amounts of physical energy unnecessarilyis not a productive way of working. Rhythm must befollowed where there is a moderate flow of theworker’s performance because a slowing pace andspeeding up makes the operator less productive. It isbelieved that the simpler motions are, the simpler thejob will be performed and it will follow that the jobswill be more productive.