I’ve written before about the benefits of visiting customers to discuss their design challenges. If nothing else, I get a brief introduction to some really interesting mechatronic system applications and often learn about new ways to use system simulation tools. I recently visited a customer site as part of a Mentor Graphics sponsored Technology Day. During a typical Technology Day, Mentor Graphics delivers several presentations in one or more technical tracks, and customers are invited to come and go as they please throughout the day. The sessions are informal and attendees are encouraged to comment and ask questions during any presentation.
Since Technology Days are held at customer sites, they often have a valuable side benefit: facility tours. Among the most interesting are engineering lab tours, where design theory and analysis meet workbench prototype. At the end of our recent Technology Day, two attendees sponsored just such an engineering lab tour…and I had an “Aha!” moment.
When we think of design, we often equate it with some new device or technology. In many ways, design is synonymous with innovation. What might be easily forgotten, however, is that most mechatronic systems need regular maintenance and periodic updates. This is particularly true where systems have an operational life of several years if not decades. Think, for example, of really big machines that either float or fly. Though state-of-the art for their time, technology’s relentless march has made many systems within these larger platforms obsolete. At some point, it’s not even possible to maintain some systems because replacement parts are no longer available. To extend a system’s serviceable life, often the only option is a complete redesign. Redesigns, however, have their own challenges since usable design documentation – detailed specifications, diagrams, and schematics – may not exist. And often the original designers are, for whatever reason, no longer around.
During our lab tour, a senior engineer described a system he currently works on – in this case a precision cable winch assembly that extends and retracts a specialized cable from the rear of an aircraft. This winch system, however, is no longer serviceable with off-the-shelf parts. Since replacement parts aren’t available, the logical next step is a system re-design, but this is one of the “no detailed design documentation exists” situations. Fortunately our tour guide attended several of the Technology Day presentations which, in turn, started him thinking about using simulation to basically reverse engineer the winch system – a “Eureka!” moment for me. Rather than design “to” specification, simulation tools can be used “to find” specifications.
While I have never really thought about using simulation, in the absence of detailed documentation, to unlock the design and performance mysteries of legacy mechatronic systems, doing so makes sense. Simulating “to find” specifications follows the same basic process as designing “to” specification: model, simulate, analyze, quantify. Simply model the system, run simulation experiments, analyze the simulation results, and use the data analysis to quantify system performance.