The compass is a DIY handheld CNC router designed to make it easier to access CNC machine processing. Unlike the conventional CNC that moves cutting tools in a fixed work space, the compass depends on you to guide your device around the workpiece. As you move, you will automatically adjust the cutting tools to stay in the programmed design path, enabling much smaller devices to make accurate and large cuts.
All of them use the optical flow mouse sensor to track the position of the device and adjust the tools using the lead screw -driven guntory. The brain is a Teensy 4.1 microcontroller.
Why handheld CNC?
The concept of the handheld CNC machine may look a little backwards at first. The CNC machine is a large mass of metal and motor, and turns the blade to cut things. How and why did you get one of these?
But when you think about it, it makes sense. CNC is a technology that can help you bring your design in your head in the real world with the help of a computer to automate production. This is great. Until you notice that the standard entry level CNC machine costs thousands of dollars and can occupy the entire room. As a result, many of our enthusiastic manufacturers will depend on the traditional methods of using cheap hand tools, such as jigsaws and handheld routers. These are affordable, small, and portable, but in order to actually bring ideas, you need skills, expertise, and stable hands.
Handheld CNC combines computer accuracy of CNC technology with standard hand tool flexibility and cost. It controls it like a standard handheld router and moves roughly according to the design, but can be automatically modified to cut the design completely. If you use the same workflow to get a design from a computer to a CNC machine, you only need to upload a tool path, set the origin in the workpiece, and move it to a place where you instruct the device. The UI screen on the front of the device indicates the location of the router accurately and warns if you are on track. The compass remains, leaving a beautiful cut that fits in a suitcase or shelf and a sophisticated CNC machine.
Compass origin
Making with the manufacturer -I have a container to release my creativity and cooperate by hand -I make a skateboard with my father at the garage when I was eight years old, until I actually lived. It was a big part of my life. Makerspace 4 years at my university. I created a compass. Because I wanted to create a device that could lower the barriers to make.
3D printing and CNC mechanical processing are great, but it can be very different for those who are not yet familiar with engineering, computers and electronic devices. There is a cutting between users and those created. These are wonderful technologies that can be created in front of you by pressing the button, but you may lose the “manufacturer” in the process. “I’m making something now!”
The handheld CNC router returns this specific interface to digital manufacturing, feels that users are part of the manufacturing process, and lower the barriers of woodworking. If you have an unstable hand or a state like Parkinson’s disease, you do not need to count yourself because it makes a beautiful handmade one.
My goal in the compass is to make it easier for woodworkers to access CNC mechanical processing and easier to access woodworking than anyone. I found a part of my identity when I found a manufacturer space, digital manufacturing, and woodworking tools. I want to help others experience the same sense, creativity, and freedom.
Where am I? XY solution
The most difficult part of this project was to make a much more aware of how to know where it was. I brushed various ways to do that -I could move around the wheels, even if I followed the wheels, according to the string potentenshaometer, TOF beacon, camera, and drawn lines, but the computer mouse tracks that movement. A space that has been decided to use the same technology as used for it. This was the simplest solution, and implementing it was the cheapest. There is no need to set up, there is no external beacon. Users still play a role in device movements.
I analyzed a lot of mice next month or so, connected them to a microcontroller, and came up with how to read them. After confirming that this works, we have found a breakout PCB for a great gaming mouse sensor, ordered four of them, and began to convert all of them into router position and direction estimation. Fortunately, I took a class Rigid motion In the previous year, this was exactly what I needed to do.
Once the sensing was functioning, I built a device and tested it with a pen instead of cutting spindle. This did not work in the first attempt! I finally got it to draw a simple straight line, and I was pleased. When I used it to actually cut something, my senses were euphoric. It was a small sine wave on the cork board, but the feeling that this robot was moving and responding to my movement was that Doremel rotated at 35,000 rpm to reduce the material and made my design. It wasn’t really the second.
Four eyes are good
The core of this project is to use four optical flow sensors at the bottom of the device to know where the compass is in the workpiece. These are small cameras that constantly monitor the surface and detect whether they move. The computer mouse has one sensor. By adding the second sensor, you can also detect rotation. Using a simple rigid dynamics, you can accurately estimate where the compass is in the space and how it is attached. Using the four sensors can provide multiple methods to calculate these position -oriented values, making the system more robust by adding redundancy and error correction.
This sensing technology achieves the same concept as Shaper’s Origin router, without needing computer vision or unique Faid Ischtape. Just set a compass on the workpiece, there is no need to set up or work mapping.
Each of these sensing methods has advantages and drawbacks. Shaper’s technology is absolute positioning, but the compass is relative. This means that using a compass means that the sensor measurement value starts drifting with a long running. This can be a problem with a large cut if it is not properly prepared, but there are several ways to counter it. The drift is minimized by using the aforementioned sensor redundant, the highest accuracy and high -sensitivity gaming mouse sensor. Start with the accurate reading value as much as possible for each step to reduce the error stackup. It is also possible to predict how quickly drifting exceeds the desired value based on the measurement of the surface quality. You can use this to encourage users to register the device again after a long interval, pause the cut as needed, and track the location to resume the design. A simple 3D printed corner bracket performs device homing tricks.
Build yourself
Most of the physical components of the compass are 3D printed so that they can make it easier to manufacture and make DIYER easier. It is very easy to assemble your own handheld CNC router. When you get all parts, it’s like an adult Lego set. All pieces have three allen orgers, drivers, and minimal soldering. (I want to make it “no solder” with a new PCB.)
First build a spindle mount, fall into a linear bearing, lead screw, smooth rod, and stepping motor. After that, everything else is mounted on an aluminum base, and the spindle mount slides neatly into the X -axis smooth rod guntory. More more of motors, sensors, and handle screws, and what remains is to route the wire. This allows you to snap with a connector or enter the screw terminal. Once assembled, the device must execute a simple calibration.
Open source
All designs and firmware of this project are open source, so anyone can create a compass and change it to make it look appropriate. If you want to put a laser on it, be my guest! Full Create instructions, code, 3D files, and BOM Online. Please make it yourself for about $ 500 I will buy a kit from my website Get a little more CNC technology.
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