The human face of design

Unfortunately, many designers only discover the flaws inherent to their designs once they have already committed to prototyping or even production, meaning the project may require expensive re-engineering or even that it may not be possible to correct it and the product's success may be limited as a consequence. For this reason, the ability to incorporate human models into design software has been extremely valuable. A number of products exist to model human factors, of which probably the best known is the 'Jack' software application, which is used as part of Siemens PLM's Tecnomatix software family. Equally, Dassault Systèmes offers the 'Human Builder' virtual ergonomic s solution, which integrates into its CATIA and DELMIA platforms. Traditionally, however, standalone human factors modelling has tended to be a highly-specialised process requiring considerable expertise on the part of the user. Equally, the software products have been fairly expensive. For this reason, human factors analysis has tended to be a separate process to design, with all the problems that are inherent to such an approach. In an attempt to address this, PTC released the Manikin modules with its Pro/EngineerWildfire 4.0 version. Designed to offer "a low-cost, affordable and scalable solution for use by the wider community", according to PTC's principal application specialist Iain Lewis, Manikin is integrated into Pro/ENGINEER. Indeed, a free, limited capability version – Manikin Lite – is currently incorporated into all Pro/ENGINEER packages, beginning with Pro/ENGINEER Wildfire 4.0 and later releases. The scalability comes in the form of additional capabilities added as one scales upwards. The Manikin Lite capabilities allow the insertion of a single, predetermined manikin into Pro/Engineer and some posturing using a reduced number of manipulation tools. The Manikin extension, however, is a mainstream human modelling solution for first-level checks of human-centric form, fit and function, incorporating comprehensive sets of libraries of manikin data, processes and tools. Manikin Analysis, on the other hand, is aimed at the higher-end user and allows consideration of even more complex ergonomic and human factors. Fundamentally, says Lewis, the principle behind this is simple. "We're trying to help people to do more of the work up front and save them cost and difficulties later on…Prior to human modelling, an engineer would go away and build the environment, then do some FEA and only at the end of that process would you make a human interact with it. People didn't think of human factors because they didn't have the tools to do so." Although Lewis concedes that it is not designed to be a rival to specialist human factors software, the capabilities of Manikin nonetheless remain impressive. Incorporating a library of a wide demographic of human models, it allows users to undertake functions such as 'reach analysis' and 'view analysis' that also gain a user's perspective of your product and 'see' what the manikin sees. The model can be fully manipulated in real-time inside a CAD model to better understand the relationship between a product and person interacting with the product. Says Lewis: "It's not just about putting a human into an environment. It's about how an individual interacts with that environment and how that environment affects that individual. It's about having a human-centric approach to design." Manikin also allows engineers/designers to place 3D human models into product designs in a series of static posture 'snapshots' that might include sitting, standing, kneeling and so on. They can augment these capabilities by using the animation tool to create animations of the manikin performing a workflow. Should the design change in such a way as to create a problem with the manikin (for instance, to require the human to do something physically impossible or dangerous), the software will flag this up. Designers can even combine animations or their manikin with the Pro/ENGINEER motion envelope to determine the full amount of free space the design will require to allow the manikin to complete the entire motion. For example, if engineers/designers want to test a design for the interior of a car door, they can create an animation where the manikin reaches and activates the handle to raise or lower the window. The volume envelope demonstrates where the elbow will go. This helps determine whether any adjustments to the door design are necessary to eliminate clashes between the elbow and the door controls. If a part is being made by a subcontractor, the designer can even generate a part that can be sent to the provider so he or she can make the proper change even without the manikin.