Saturday, July 20, 2013

Open Source Motion

For more than three decades I’ve been a part of an evolution that has combined the microcontroller with power electronics. Over that time, motor drives have evolved into useful building blocks; however they have become “black box” building blocks. While they may use standard communication protocols such as Rs485, Ethernet or Can, each manufacturer created different twists to their product in the name of product differentiation. Drives got smarter, but that intelligence was hidden behind a veil of proprietary user interfaces. External controllers can communicate with the drives for more complex applications, but standalone field programmability is limited. 

Contrast this with the smartphone. It too serves a “black box” function, communication, but by embracing operating systems such as Android to control the phone hardware it flaunts its intelligence and allows users and third parties to create apps that may or may not use the “black box” functionality. Critical phone functions must be accessed through a strict Application Programming Interface (API), but other resources such as memory, USB, Bluetooth, Touchscreen and WiFi are available for general programming by users or third parties through the operating system. To achieve the same flexibility in today’s drives, it is necessary to have an external “brain”, such as a single board computer or PC to run system level software. 

While this is reasonable for stationary applications or small production runs, it can be challenging and expensive for mobile, off grid, standalone or higher volume applications. By incorporating Android, Linux or other “open source” operating systems, drive manufacturers can release the creative potential of their users yet keep the drive operations proprietary. In many systems the drive is already the largest consumer of power and space and an open source drive would eliminate whole cabinets of power supplies, computers and other gear. Several such drives and other hardware can be connected together through CAN or other standard interfaces to form an autonomous local network for flexible coordinated motion. 

In the ad hoc “Maker Culture” there are already examples of open source motion. Perhaps it’s time for the mainstream drive manufacturers to take a look. 

As always, questions, comments and suggestions are all welcome. I can be emailed at solutions@gboxllc.com. 


References
Maker Movement; http://www.economist.com/node/21540392/ 
Embedded Linux; https://en.wikipedia.org/wiki/Embedded_Linux 
Open Source Initiative; http://opensource.org/