By Richard Lee – Lee Engineering Inc.
Is it human nature to add complexity when solving problems? Whether engaged in the design, engineering, cooking, government, management, staffing a department, programming, or even writing sentences, we tend to add features and complexity.
Sometimes "more" becomes the root cause of many problems later. To make matters worse, we often add rather than subtract when fixing new situations! It can become an endless cycle. A band-aid on top of a band-aid. Over-engineering.
The add-more approach often increases costs, waste, complexity, bureaucracy, maintenance, and lead time slows productivity, and may be more prone to failure.
Adding is frequently not the best strategy. It may be the worst approach to solving some problems. Still, adding complexity is the most used strategy. Many overlook that option even when a better method is to subtract and simplify.
Why do people tend to add rather than subtract? Does adding to a design or process create a visible legacy? Is it a monument to our hard work and creativity? Have you ever looked at a Rube Goldberg contraption while someone else comments, not sarcastically, about the ingenuity that must have gone into it?
Ironically, finding a simple solution for a problem or design can be the most challenging approach, but it always looks easy in hindsight. When done well, there is little evidence of the hard work involved!
In my experience, making something simple and elegant takes much more thought up front and a few more design iterations.
Sometimes subtracting and simplifying goes against popular opinion. You may be tearing down someone else's legacy or contributions if you find ways to take an existing machine, product, or process and make it better by removing parts, features, or steps. If you propose eliminating an "ingenious" Rube Goldberg legacy contraption, protests and obfuscation by the originator may occur.
Ultimately, the added effort of creating a simple solution is usually worth it. However, when looking at the simple solution, few people will ever know that the first draft was a more complex, "ingenious" Rube Goldberg solution.
It turns out that researchers have studied why we use adding complexity as the go-to strategy rather than subtracting and simplifying. Here are a few links for further reading:
Why Our Brains Miss Opportunities to Improve Through Subtraction | University of Virginia School of Engineering and Applied Science
The 'law' that explains why you can't get anything done - BBC Worklife
Subtract: Why Getting to Less Can Mean Thinking More - Behavioral Scientist
Less is more! Human brains struggle to be minimalist, scientists say | Daily Mail Online
Subtract: The Untapped Science of Less:
And, of course, there is Dilbert!
Homepage | Dilbert by Scott Adams
A straightforward proven method can yield substantial cost savings for machines and products consisting of mechanical and electrical parts and assemblies.
Depending on the project, savings of over 40% can be achieved, in my experience.
The 1st key to this proposed method is to 1st generate a structured and costed bill of materials (BOM) to work from.
When sorting the list by (Unit cost) x (quantity used) from largest to smallest, you may find that as little as 10% of the parts on top of the list make up between 50% to 80% of costs! It’s similar to the well-known 80/20 rule.
This is all great news because now you can work on a small, targeted list to make a huge impact.
To get the maximum savings, you'll also need to make a similar list of the sub-assemblies or sub-systems, sort them, and look for ways to eliminate parts altogether, or simplify by combining several parts into one integrated part, such as Sheetmetal, casting, molded, or 3D printed component. You can also make a list of functions and look for ways to combine or eliminate some functions.
I’ve seen this work with industrial machinery consisting of hundreds or thousands of parts.
What is your engineering team’s approach to using timing diagrams in machine development?
It is such a valuable tool from the conceptual stage to production that I'm surprised when I find that some machine builders are using them seldom or not at all.
It is helpful to start the timing diagram in the conceptual phase, even before the actual 3D modeling starts, especially if many motions are involved. A chart makes it easy to find opportunities to overlap motions and reduce overall cycle time.
Whether your motions are cam or servo driven, the diagram communicates what motions need to happen and how each device motion relates to the others.
As the 3D model develops, the timing diagram should evolve in parallel.
The diagram can be made in a 3D CAD environment, a sketch tool, spreadsheet, on paper, or with a 2D kinematics tool, as shown here, it's pretty simple and fast to keep it updated as changes are needed, and you may also include inertia, torque, and other dynamics calculations.
The curves generated by most software tools can be exported and used to create physical cams or translated into parameters for servo motions for use in the control program.
Later, as the machine begins testing and moves into production, it becomes a great way to consider what-if scenarios, train operators, troubleshoot problems, and consider future upgrades or modifications.