How to make prototypes of drive systems? How long does it take and how ‘good’ are they?

There are several different approaches to creating a prototype of a drive system. We have listed these with the details and benefits highlighted below.  

Using the existing motor (standard motor or in production), transmission and controller.

• Design mechanical, electronic and electric interfaces accordingly.
• Accept the potential trade-offs in performance, size and capability.
• The software to simply make a motor spin, control torque and speed should be readily available.
• Typically get started straight away.  

Prototype motor, transmission and controller.

• Prototyping a motor provides the design freedom for performance, dimensions and interfaces.
• Upfront simulations and design methods get you really close to final product characteristics.
• Laser cutting laminations, manual winding or winding on a prototype winding machine, lathing and milling parts for rotors and stators, 3D printing, and manual assembly are methods that make prototyping a matter of weeks if the materials are available. The magnets might have to be made to order.
• Transmissions come in many shapes and sizes: traditionally gears, belts, chains, but also friction, hydraulic, magnetic power transmissions are available and must be selected for the specific application.  
• Controllers can either be designed and manually built, or a development board from established PCB companies might be sufficient.
• Software must be either written or an existing code modified. With the right team working on it, it will take some days, maybe weeks.

Complex and innovative technologies.

• The more complex the system is, the longer it takes to get one single prototype done, particularly the first one, as it will take some iterations to get it spinning.  
• Typically, if new materials are used, their production method – even for prototyping – must be figured out, like the right parameters, the correct thicknesses, the surface properties etc. That requires some loops and investigation. On a component level, you can learn a lot, but in the assembly more challenges are likely to surface.

Conclusion
Depending on the requirements for the drive system and application, it can take only a matter of days to use and adapt an existing drive system if you are willing to accept the trade-offs. A full prototype of a drive system can be built in a matter of weeks. If overly complex ingredients are put into the mix, it may extend the timeline, depending on their nature and maturity.