A factory that manufactures speakers has a conveyor belt at the end of the manufacturing line which delivers the final product. The facility is designed such that the packaging station is not aligned to the manufacturing assembly. Hence a worker has been assigned to transfer them to the packaging station -using both hands – where they are hand packaged by other workers to be stored or shipped. For this scenario we have selected a man of 178.1 cm which is approximately 50th percentile in ANSUR database and 77.7 kg, which is also approximately 50th percentile. The simulation consists of a basic task of picking up the speaker and placing it on a table. The simulation is done in Tcnomatix Jack software in order to analyze the ergonomic effects between two scenarios as stated below; • Scenario 1: The worker grabs the speaker far away from his core, making him lean forward and reach out to the product. Then he carries the product to the packaging station using his both hands. • Scenario 2: The worker grabs the speaker in a more ergonomically correct position; keeping the horizontal distance between his body and the product optimal. Then he carries the product to the packaging station using both his hands. We have assumed that the change in aesthetics of the two speakers has very little effect on the final results since both are of same weight. We are comparing timing and L4/L5 Compression Forces for each scenario.

1. Ergonomic Analysis in Jack Simulation
ISE 5463: PLM – ERGONOMICS
Prepared by
Umang Tuladhar
Yogesh Gawade
Janindu Samaraweera
Vinodh Balasubramanian

2. Background
A factory that manufactures speakers has a conveyor belt at the end of the manufacturing line which delivers the final
product. The facility is designed such that the packaging station is not aligned to the manufacturing assembly. Hence a
worker has been assigned to transfer them to the packaging station -using both hands – where they are hand packaged by
other workers to be stored or shipped.
For this scenario we have selected a man of 178.1 cm which is approximately 50th
percentile in ANSUR database and 77.7
kg, which is also approximately 50th
percentile. The simulation consists of a basic task of picking up the speaker and placing
it on a table. The simulation is done in order to analyze the ergonomic effects between two scenarios as stated below;
• Scenario 1: The worker grabs the speaker far away from his core, making him lean forward and reach out to the
product. Then he carries the product to the packaging station using his both hands.
• Scenario 2: The worker grabs the speaker in a more ergonomically correct position; keeping the horizontal distance
between his body and the product optimal. Then he carries the product to the packaging station using both his hands.
We have assumed that the change in aesthetics of the two speakers has very little effect on the final results since both are
of same weight. We are comparing timing and L4/L5 Compression Forces for each scenario.

3. Constraints
The items, human and objects used in the simulation are as follow;
Item Description Constraints
Male worker 50th
percentile male of ANSUR database Ht.:178.1 cm, Wt.: 77.7 kg
Conveyor Conveyor from Jack library Ht.: 70 cm
Packaging table Industrial table from Jack library Ht.: 80 cm
Speaker 1 Rectangular Speaker Wt.: 5 kg
Speaker 2 Cylindrical Speaker Wt.: 5 kg
Simulation
The table below discretely describes each event occurring in the simulation;
S.N. Task Timing Description
1 Go 3.0 sec Worker walks to a position to carry speaker 1 as described in scenario 1
2 Get (speaker 1) 2.4 sec Worker reaches out to grab speaker 1
3 Put (speaker 1) 7.3 sec
Worker carries speaker 1, takes it to packaging table and places the speaker on the
table.
4 Go back 4.9 sec Worker walks back to a position to carry speaker 2 as described in scenario 2
5 Get (speaker 2) 1.0 sec Worker reaches out to grab speaker 2
6 Put (speaker 2) 6.8 sec
Worker carries speaker 2, takes it to packaging table and places the speaker on the
table.
7 Go 5.0 sec Worker goes back to the conveyor.

4. Results
Lower back analysis: The following is a lower back analysis (L4/L5 lumbar compression) that was generated after simulating
the two afore mentioned scenarios.
As documented in the chart, there is a considerable difference in the lumbar compression (L4/L5) in the two scenarios.
When the worker adapts to a more ergonomically correct posture and practice, he feels less strain on his lower back. As
mentioned above in the chart, it’s visible that worker will have to face less stress in lumber (approximately 1500N) while
getting and putting the speaker two than the speaker one.

5. Timing report: Now the timing report generated from the simulation is shown and discussed below;

6. Required time Calculations: From above report we can determine the time required for the worker to complete the tasks
in two different scenarios as shown below
Scenario Tasks involved Total Time Remark
1 Get solid + Put solid 2.41+7.27 = 9.68 sec Solid = speaker 1
2 Get cad object + put cad object 0.98 + 6.84 = 7.82 sec Cad object = speaker 2
Difference in time 1.86 sec Time saved in scenario 2
Clearly there is a difference of 1.86 sec each time the task is completed; not having to reach out for the speaker saved the
worker 1.86 sec each time he performs the task. When we are taking into consideration the fact that this operation is a
repetitive one, and a single worker might be doing the same task for a shift of 8 hours a day, we can quite easily predict that
encouraging ergonomically correct practices will result in better efficiency of the worker and enhanced productivity in the
workstation.
Conclusion
The lower back analysis and timing analysis done from the simulation are verified, that using ergonomically correct posture,
no matter how minute, on the long run can result in significant difference in the end result in terms of workers health,
overall efficiency and productivity in the workstation. Therefore, in any type of working environment, workers must be
encouraged to adapt ergonomically correct practices, and the companies also must provide an environment that
complements the worker’s requirements.