Build Ergonomics
Build ergonomics - the level of effort for a build, can be evaluated meticulously. We need to define:
- Number of steps
- Time involved
- Difficulty
- Complexity
Number of Steps
Any single step can be defined as one operation with 2 hands. For example, take a nut and insert it into another 3D printed piece. That is One Step. Or, take a nut and put it on a bolt. That is one step. Done manually - that is a minute - done with an impact wrench - it's seconds.
Time of Build
Counting the number of steps as such gives an idea of build complexity. A build with 3525 steps - with a minute per step, would take 60 hours to complete. That is a realistic estimate of, say, a tractor build.
About one minute per step is a reasonable, rough estimate for many actions. This principle is an effective way to assess overall build time: simply take the number of steps: say 254 - and guess that it it took ~4 hours to do a build.
To reduce build time - we can assess each step - and see what optimization can be made: such as using power tools, CNC tools, or redesigning for simplicity. The last point has the most impact on build time: it separates good design from bad design.
Difficulty of Build
In terms of human stamina - the most important determinant is weight of the build. Lifting 1 kg 1000 times is much easier than lifting a ton one time. Heavy objects fatigue a builder - such as when building a house or a tractor.
Complexity
Design determines complexity of build. If a designer pays extreme attention to build complexity, then they will design it for easy manual assembly, low tooling requirements, and simple design.
Part of complexity - is access to documentation that reduces complexity. For example, having easy-to-access tools and instructions for deconstruction.
In today's world - sleek-looking black boxes dominate the product landscape. What about designs that are designed for easy repair? The sleek-looking black box is good design - if it can be repaired/reused. For example, it appears that Tesla cars are not good in this regard - see Tesla Repair.