Prediction Analysis of Human Motion Dynamics using Digital Human Modeling tool JACK

Abstract

Background: Digital human modeling (DHM) offers human factors or ergonomics learner the promise of an efficient means to simulate a large variety of ergonomics issues early in the design of products and manufacturing workstations. Most of the products and manufacturing work settings are specified and designed by using sophisticated computer-aided design (CAD) systems. One can simulate issues regarding who can fit, reach, see, manipulate, and so on by integrating it.

Objectives: The objective of this study was to understand the behavior of different postures in constrained and awkward workplaces. Digital human modeling (DHM) software called JACK was used to obtain the posture data. It was compared with data collected through experimental studies in the laboratory. Observations were analized for the different activities like bend and arise, lifting, stooping, with and without load which majorly contributes for occupational hazard at workplace. The output generated used in positioning of machines and other equipment to optimize cycle time and avoid hazards. This case study was carried out on Press machine in bolt manufacturing process. Steel rod is used as raw material for making bolt. The workers were forced to perform task in awkward working position for lifting steel rod from its place in a very restricted position.  Similar activities of different parts of the body occurred during the machine operation. It involves moving the material manually from using the left hand, holding and lifting from the ground, feeding it inside press machine using both the hands one by one in seventeen steps and Controlling the speed of the machine, collecting cut bolt parts after cutting it.

This paper focuses on the process of data acquisition which serves as an input for Force Solver, Lower Back Analysis. The data which is collected and identified as Non-Value adding activity was experimented in between time and Performance Level for the entire percentile ranging from 99, 95, 50, 5, and 1, using JACK Human Simulation tool.

Methods: Digital human modeling (DHM) JACK is process simulation software. It is considered for a digital representation of the human inserted into a simulation or virtual environment to facilitate prediction of safety and performance. DHM is intended to reduce or eliminate the need for physical prototypes in new product and process design, and enables engineers of various disciplines to incorporate ergonomics science and human factors engineering principles in earlier phase in the design process. These methods can provide real cost savings alternative.

Conclusions: The critical evaluation and verification of the results are presented in the paper. The analysis of the different graph for the entire percentile manifested that most of the Joints are subjected to the incursion of high number of Forces during the verisimilitude time zone. It has been observed as the common activity of bend and arises in partial and full mode. Inference from the graphical representation is reflected and contributed in learning and prediction of the awkward postures. The outcome from the analysis will be helpful in future factoring the human element into manufacturing and the implementation of the proposed methods a n d technique. This result will add value in workstation design and safety for reducing occupational hazard and will bring competitive advantage.