Project Summary: This project will investigate the effects of pregnant women's altered shape and size on their seated posture. The effects will be simulated by developing a digital human environment. The foundation of this human simulation environment will be an induced optimization-based posture prediction model. A suite of simple web-based models will be developed and combined with experimental laboratory exercises for use in a freshman course designed for the Women's Studies minor at Texas Tech University, with the goal of attracting women students to the engineering disciplines. The PI will collaborate with the Cross Cultural Academic Advancement Center, Texas Tech University to develop a summer workshop at the PI's lab (Human-Centric Design Research Laboratory) for the Native American Summer Bridge Institute (NASBI). The week-long summer workshop proposed in this education module will focus on computer-based digital human modeling and simulation from an engineering point of view in order to attract Native Americans to pursue degrees in engineering.
Intellectual Merit: The proposed research seeks to provide a scientific foundation for investigating the seated posture of pregnant women and to develop a unique optimization-based model for the prediction of seated posture in pregnant women. Digital human modeling and simulation has revolutionized the way new products are designed, built, operated, and maintained. Expected benefits include improved quality and the reduction of product development time and costs. During pregnancy, a woman's body undergoes significant physical changes that can impact her safety in vehicles and workstations. There are a number of modeling and simulation packages including JACK, RAMSIS, SAFEWORK, ANYBODY, etc. with posture prediction capabilities. However, none of them has incorporated the needs of pregnant women. Moreover, currently available packages are either based on empirical data or model few degrees of freedom (DOF). This project will develop a new optimization-based model that yields significant advantages: 1) no prerecorded data is required; 2) the human model can react to infinitely many scenarios; 3) a computationally efficient approach permits real-time operation; 4) there is no penalty to the speed of operation when a large number of DOFs are used; and 5) added functionality, such as obstacle avoidance, manipulation of multiple end-effectors (feet, hands, and head), or stipulation of orientation for various body segments, is easily achieved by incorporating additional constraints in the optimization problem. The research addresses the following questions: 1) how do changes associated with pregnancy affect women's seated posture; 2) what are the low-back biomechanical loads for pregnant women sitting at a workstation; 3) what are the risks related to layout design for pregnant occupants; and 4) what design improvements can be made to permit comfortable posture?
Broader Impacts: The proposed work has ramifications in a potentially broad range of areas, such as (i) modeling posture in the morbidly obese; (ii) designing automobile/airplane interiors to better accommodate the needs of pregnant women; and (iii) modifying regular workstation design for pregnant women. This project will create ways to make science and engineering more inclusive to underrepresented groups through the development of an innovative course and outreach program. To achieve this goal, a family of simple web-based models will augment students' classroom instruction by way of experiment-based laboratory exercises. These models will be intentionally designed for students in the Women's Studies minor at Texas Tech University in order to attract women to careers in engineering. A summer workshop will be developed in the PI's lab for the Native American Summer Bridge Institute at Texas Tech University targeting Native American high school students. Texas Tech University began its annual NASBI in 2008. The program invites about 40 Native American high school students and their parents to participate in activities that introduce them to academic courses, campus activities, cultural exploration, and college life. The proposed workshop will demonstrate advances and advantages of digital human modeling and simulation. Active recruitment to engineering studies will occur during this event with full participation of the research group.
The outcomes of this project includes following components: 1. We have developed unique and useful methods from this project. These methods will have high impact to human modeling and simulation community. Intellectual Merit: A physics-based optimization algorithm for seated posture prediction in pregnant women has been developed. This algorithm is useful in product design, manufacturing, etc. A systematic weight determination algorithm has been developed for cost function weights in posture prediction. A general algorithm for calculating support reaction forces in seated and standing cases has been developed. Also a new stability criterion for seated posture has been proposed and validated. Broader Impacts: a) Novel Algorithms All algorithms are useful in product design, stationed design and analysis, or any scenarios that involve human beings. b) Outreach Programs During the course of this project, we were fortunately to develop the outreach programs (Native American high school students and Dunbar Middle school students). We are so happy that these outreach programs have changed their life and college and engineering have been accepted as their career goals. c) Minority students participated this research program Several female students have participated this research projects: Robyn Boothby, Aimee Cloutier, Katharine Burns, and Qiuling Zou. 2. Journal Publication Gragg, J., Yang, J., Cloutier, A., and Pena-Pitarch E., Effect of Link Length Determination on Posture Reconstruction, (in press) Applied Ergonomics. Howard, B., Cloutier, A., and Yang, J., Physics-Based Seated Posture Prediction for Pregnant Women and Validation Considering Ground and Seat Pan Contacts, Transactions of ASME Journal of Biomechanical Engineering, Vol. 134, Issue 7, 071004-1-10. Howard, B., and Yang, J., A New Stability Criterion for Human Seated Tasks with Given Postures, (in press) International Journal of Humanoid Robotics. Howard, B., and Yang, J., Calculating Support Reaction Forces in Physics-Based Seated Posture Prediction for Pregnant Women, International Journal of Robotics and Automation, Vol. 27, No. 2, 2012, 247-260. Zou, Q., Zhang, Q., Yang, J., and Gragg, J., An Inverse Optimization Approach for Determining Weights of Joint Displacement Objective Function for Upper Body Posture Prediction, Robotica, Vol. 30, Issue 2, 2012, 389-404. Gragg, J., Yang, J., and Howard, B., Hybrid Method for Driver Accommodation Using Optimization-Based Digital Human Models, Computer Aided Design, Vol. 44, Issue 1, 2012, 29-39. 3. Research results dissemination: We have presented the research results in the following conferences: ASME DETC 2012 SAE World Congress 2012 ASME DETC 2011 SAE World Congress 2011 HCI International, 3rd International Conference on Digital Human Modelling, July 9-14, 2011, Orlando, Florida, USA. 13th AIAA/ISSMO Multidisciplinary Optimization Conference, Sept. 13-15, 2010, Renaissance Worthington Hotel, Fort Worth, Texas, USA. 1st International Conference on Applied Digital Human Modeling, July 17-20, 2010, Miami, Florida.
