Foreword The ability to digitally simulate how humans interact with a product has the potential to revolutionize the way companies design@ build@ operate@ and maintain new products. Digital modeling and simulation techniques have already proven their ability to significantly reduce the cycle time and cost of designing new products@ and have generally improved the quality of products and made them faster@ easier@ and cheaper to produce@ operate@ and maintain. But many products??such as high performance aircraft and spacecraft?? present additional design challenges in human factors. To get the greatest performance@ comfort@ and safety from these products@ engineers need to know early in the design process how effectively and efficiently humans will be able to interact with them. These challenges becomes increasingly important as businesses expand into global markets@ where the success of new products depends on accommodating a greater diversity of human sizes@ shapes@ and other physical characteristics. Through accurate digital modeling and simulation of human interactions with a product@ all stakeholders in the development of the product??marketing@ engineering@ production@ and support??can visualize the design and share their concerns about it and make suggestions for improvement. Such evaluations will allow design decisions to be based on a broader understanding of the user before development resources are committed@ and will eliminate many additional??and typically unnecessary??steps that often occur later in the development and support processes. A simple evaluation of manual and visual access for adequately installing and inspecting components in a product@ for example@ can save many unnecessary steps and thousands of labor hours later on@ during the production and maintenance of the product over its lifetime. So in an age focused on getting better@ faster@ and cheaper results through computer technology@ the development of effective digital human modeling capabilities seems to be a logical next step for dramatically improving the cycle time@ quality@ and cost of producing ergonomically efficient designs. For those companies that value ergonomic thinking and taking the perspective of the customer@ assembler@ maintainer@ and operator during the design process@ investments in hardware@ software and training for digital human modeling and simulation will pay big dividends. We must keep in mind that@ while the future may belong to those who plan@ it also belongs to those who implement processes@ such as digital human modeling@ that improve the speed@ quality@ and effectiveness of how we think and what we produce for mankind. In this book@ Don Chaffin explores various examples of how digital human modeling has been implemented in different fields. Because these studies show both the promise and the problems associated with this emerging technology@ they provide a good foundation for further development in this important field. Accordingly@ they should be evaluated carefully and applied fruitfully to integrating this new technology into the design process.