Developers/Inventors/Integrators/OEM … and just tinkerers
If you're a developer, inventor, systems integrator, potential OEM, or just an interested experimenter -- you've found the right place. These developer pages explain the modular organization of the hardware and software components of our ShopBot Control System. If you’d like to create or modify your own tools or robots, or use our systems in other products, we lay out here how the elements work together to control and drive CNC equipment. Most of the designs, schematics, and software are “open” and we make the hardware modules available at reasonable prices to any who would like to make use of them.
New Project at ShopBot:
Our own current development project and platform is a new, small-size, job-oriented “Smart Digital Power Tool”. It is an open-development, open-hardware, open-source, and open-manufacturing project. We call it a “Handibot”. With the Handibot we hope to showcase the power of digital tools for all types of jobs as well as the power of the community to innovate compelling applications, drive adoption of the tool, and illustrate a new type of distributed manufacturing that digital fabrication makes possible.Read about the new ShopBot Handibot Tool Project
Use It / Try It:
Control Systems have been used to implement a number of different
types of automation equipment and to retrofit other equipment. Our
basic system is highly configurable; making available 1 to 6 axes of
simultaneous motion under software control. ShopBot software can run
as your primary digital fab interface or, in the background,
encapsulated in your own custom interface. Our software is free to
download and you can study the examples of custom controls in the
"For Developers" folder and the detailed instructions in the
“Programming Handbook”. The software has a “Preview Mode” that
allows simulating and testing your files or applications.
Non-Proprietary Control Language:
The CNC language used to create motion and to control a tool with ShopBot software can be either g-code or OpenSBP. G-code is sometimes considered the industry standard, though it has numerous variations and is not at all intuitive for new users. OpenSBP is a g-code-like, but human readable, “Open Syntax” for CNC that was developed and contributed to the public domain by ShopBot ("www.opensbp.org). Take your pick. For interfacing with older CAM software or equipment, g-code may make more sense. If you or your users have little or no CNC experience and will be working with the code or creating custom applications, OpenSBP is much easier to interact with and provides more programming options.
Committed to “Open”:
ShopBot evolved from the concept of making the amazing power of digitally controlled tools accessible to individuals and small shops. We are all about empowering people with digital fabrication capabilities. When we started almost 20 years ago, the first ShopBot was a free set of plans and instructions, a list of parts to purchase at the hardware store, and some motors and electronics that we packaged and sold. We were basically “open source” before we knew what it meant. Our software remains available for free download and updating, along with pin-outs and wiring diagrams for our Control Cards and Control Boxes. Importantly our community site for “open distributed manufacturing”, 100kGarages.com, freely supports small shops doing digital fabrication of all types using any equipment. At the moment, we are working on the development of a new, transitional Control Card. Our goal is for it to run the current ShopBot PC Control software while at the same time being compatible with running an alternative firmware that represents an emerging open source, and potentially quite powerful, CNC system. The open CNC system is one that began with “Grbl” for Arduinos (Skogsrud) and evolved through TinyG (Porter & Hart) to now run on the Arduino DUE (Hart, Porter, & Giseburt). We expect that this system will eventually support communicating with the ShopBot Control Card from virtually any type device. [See the outline of our “OPEN” eco-system for CNC (LINK).]
Experimenters and CNC Hobbyists (a little realism before you dig in … or maybe it’s just advertising):
We have always built CNCs ourselves and enjoy doing it, and for a
while we sold kits for the adventurous (see our
History). But the
reality is that in this day of affordable CNC (be it a ShopBot or
another tool), the build-it-yourself approach is only a good option for
a few hearty souls. If you just need a CNC to make stuff and your time
is valuable, then you are probably better off buying a complete tool
that's ready to go to work for you. It is an unusual individual who can
actually pull together all the required components at good prices.
If you are one of those few who really, really, want to build your
own, great! We get it … and appreciate you. Consider using one of our
Control Systems as the core component of your CNC or robotic project. As
described below, we offer several different types and levels of
solution, in each case getting you part way to your goal with proven but
highly flexible software and control components.
We are also happy to sell any stock mechanical components of our tools. Just contact our Development Team for pricing.
Upgrading Older (non-ShopBot) CNCs:
Many older CNC tools still have excellent mechanical components, even though their motion and control systems may have become outdated. ShopBot Control Systems can provide a very affordable upgrade alternative for these tools. Some work will be required to bracket and adapt motors to the existing tool. But once the mechanical link is made, you are ready for high-performance cutting and machining.
Overview of ShopBot CNC Controls and Drive Systems
ShopBot’s Control and Drive Systems are modular. The diagram below lays out the basic components and provides a way of thinking and a set of standard names for components of our CNC systems.
ShopBot CNC Controls and Drive System. By this term we mean the whole CNC motion production system; this is what we provide with a CNC tool.
ShopBot Control System refers to
the CNC intelligence and software control system. This includes the
ShopBot Control application software that is running on a PC, its
connection to the Controller Card, the Controller Card and the
software/firmware on the card. The PC software generates motion profiles
and encodes and transfers them to the outboard device, where the
information is translated into step and direction instructions that
directly drive stepper motor action. Step and direction information can
be used to activate many types of generic, motion-production drivers or
devices. The ShopBot Control System is the smallest chunk of ShopBot
Control stuff that can practically used. The
ShopBot Control Software application running on the PC and the
Control Card are conceptually separate
parts, but they fit into an integrated system and have no capability
without each other. Note that purchase of a Control Card is, in effect,
purchase of a ShopBot software license.
Our development team, in collaboration with others outside ShopBot, are working on a next generation Control Card. This will be a transitional Control Card because it can be loaded with ShopBot firmware and function using PC-based application software as described above. Alternatively this card can be loaded with firmware compatible with the evolution of the TinyG, open-source, CNC controls. Because this system shifts much of the CNC processing to a more powerful micro-controller on the Control Card, less of the work needs to be done by user-interface devices communicating with the Control Card. Practically, this means that it will be much easier to develop “thin” applications for running CNC tools and will mean that CNC apps will be developed for a wide range of devices that can easily interface to your ShopBot Control Card. We intend to contribute to the development of these open-source CNC applications. Please see the extended discussion of our “road map” for this project.
The Control Card is fitted to an Interface
Board to make the electrical connections from the Control Card
conveniently available for use. Our Interface Boards provide isolation
for power for the Control Card, isolation for USB communication, and
isolation for all I/O. They also contain relays for controlling
routers/spindles. Stepper motor drivers are plugged directly into
connectors on the Interface Board. We offer levels of Interface Board.
The lowest two levels allow a for generic Step & Direction connections
so you can easily hook up your own motor drivers rather than the ShopBot
provided drivers specifically matched to the Board.
To create any kind of physical CNC action, the system needs to
include Motor Drivers and
Motors. The Interface Board is
connected to the Motor Drivers by Driver
Connectors, and then the Motor Drivers are connected to the
Motors by Motor Cables. Our
Control Boxes are sealed and
contain/house/protect the Controller Card, Interface Board, and Motor
Drivers. Control Box systems include an electrical disconnect switch,
contactors for controlling routers/spindles, interlock safety switches,
and a Roxtec seal for managing cable entry into the box.
The organization of our system is
modular with the Control Card as core module. This modularity has
allowed our systems to evolve more efficiently and by using common
components to provide more continuity between systems and over time. For
example, we have evolved through many versions of our Control Card, but
today’s version can be plugged into the interface board of any ShopBot
of any age and provide the tool with current features and capabilities.
We currently have three levels of Control and Drive System offerings.
A Basic System that will run small and medium size stepper motors. This is the system we use in our Desktop CNC Tools and Handibot Tools.
Click here for full description [PDF]
A Standard System that will run medium and large size stepper motors and is the basis for all our PRSstandard Buddy and Gantry Tools.
Click here for full description [PDF]
An Industrial System that uses closed-loop stepper motors and underlies our “production performance” PRSalpha Buddy and Gantry Tools.Click here for full description [PDF]