More ShopBot History

In 1994, Ted Hall showed an early version of a ShopBot to friends and fellow members of the Triangle Woodworkers Association, a large woodworkers group in the Raleigh-Durham-Chapel Hill area of North Carolina. Excited by what could be cut, machined, and produced with CNC, his idea was to make these tools available to other woodworkers as affordably as possible. A key feature of ShopBots, starting with this earliest model, was to put as much of the movement intelligence as possible in the software of the PC to minimize the need for expensive control system electronics. The early ShopBots were 'closed-loop,' having an encoder-based feedback system that monitored the position of the cutting tool. Making the tool closed-loop was one way of making it affordable, because an inexpensive cable-drive system could be used to move the tool while position was accurately adjusted by the feedback system. Feedback was a natural, biologically-inspired approach to tool control for Ted, given his background as a neurobiologist. ShopBot received a patent for the way the drive and feedback system worked, and for the modular arrangement of the carriage system.

ShopBot's current PRTalpha tools continue in this tradition of closed-loop, stepper-driven motion. Stepper-motor-motion is a natural for computer control of tools because of its inherent accuracy and digital nature. When combined with feedback and the speed of our alphaStep motors , it is hard to beat.

You can see in the top pictures that the early ShopBot prototypes were made largely of plywood. One of the neat features of this tool was that it could cut out a copy of itself in plywood. Thus, it was largely 'self-replicating' -- you could use one tool to make more; just add a couple pieces of tubing, plastic wheels, and some motors (almost a self-replicating robot). Unfortunately, as the tool was scaled to larger sizes, the plywood and tubing frame did not prove stiff enough for serious cutting and machining, and ShopBot lost its self-replicating capabilities to stiffer metal frames. Nonetheless, many components of today's ShopBots are produced with ShopBots.

(Bill Young assembling his early,
utility-strut, ShopBot)

In the absence of self-replication, our philosophy for the first production ShopBots was that they be made simply and as much as possible from parts that were readily available to anyone at the hardware store. Keep the parts simple and easy to get -- the robotic capabilities and complexity could be put into the control system and software. This would make it possible for people to build and maintain their own CNC tools from a set of simple plans, and they would only need to buy the specialty motors and control system. The 'hardware store' philosophy gave our early tools an erector set look, being largely constructed from utility strut -- but they were low cost and they really worked.

Well, we quickly found out that we could provide the parts from bulk purchase at about 1/3d the cost of the hardware store, and that most people preferred to buy the parts at a low price from us rather than running from store to store in search of them all (for example, ShopBots required 36 patio door wheels for motion and these were usually not available at a single Home Depot). ShopBots became known as a 'kit' tool and putting a ShopBot together from the set of small parts was an 'exciting' challenge ... we are still happy that so many people enthusiastically and successfully did it and embraced the idea of affordable robotic tools.

ShopBots have changed. There are people interested in building their own CNC, but there are many more who simply want an affordable CNC to make or produce their parts or products. They want a CNC to use and would rather not have to build their own tools from scratch. Today's ShopBots are for these individuals. Our tools are for people excited to put the capabilities of robotics to work in their shop. They are fast, powerful, precise and robust. And, ShopBots are no longer kits. They are shipped as 4, pre-assembled modules -- ready to be set-up and quickly put to work. For more about getting productive with CNC read Before you Buy a CNC.

We have not given up on our enthusiasm for people who would like to build their own CNCs. It's an idea that still has an appeal to many of us here, and at ShopBot we still provide a comprehensive range basic software, control components, and mechanicals for anyone who wants to 'build their own' CNC tool.


Each new ShopBot tool comes bundled with two powerful software programs to create CNC projects.

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