Design for Automated Assembly
Design for automated assembly is really about giving consideration to automation constraints during the design process. No design is impossible to automate. DFAA just ensures that the automation is not crazy expensive to build, and the finished assembly can operate robustly and with low defects. A difficult to automate design usually reveals itself at the end of the process, when the line exhibits yield and stoppage problems.
Creating an automation concept is all about creating a logical assembly sequence which doesn't require repositioning the base assembly too much. One also has to consider how stable the assembly will be as it moves between stations, and if there are any parts that have difficult assembly trajectories which must be considered.
Once a basic plan is in place, one can consider the transfer system, and design how the assembly will move from station to station. Is it a small assembly that can be done on a rotary indexing system, or is larger, needing a pallet transfer system?
After the transfer concept is set, one can dig into the details of each station. The work starts with the work-holding strategy, and devolves into the fixture concept and part gripping ideas.
Finally, one must consider the feeding strategy, which is often the most difficult challenge of the process. Once a part is located, loaded and locked into a gripper, assembly is generally a straightforward matter. The challenge is to find a cost effective means to do so. Is vision required? Can it be bowl fed? Should we use matrix trays? What about a tube feeder? All good questions that need to be answered early in the process to ensure a good result at the end.