moving things (and lasers!) using printed circuit boards
I have been trying double for about a year
Axis pointing mirror for laser.
Initially I built a laser steering module with a solenoid.
I then purchased some Texas Instruments TALP1000B modules from a science surplus store and experimented with them.
The advantage of the Texas Instrument Module is very small, but it is very fragile and can no longer be purchased.
I have an obvious advantage in my DIY module (
It can work with purple laser and phosphorus light screen.
DIY modules are also powerful and can be made with easily accessible parts.
The disadvantage is that the solenoid makes the module large and heavy, and can only provide tension, making the drive circuit and limit control complicated.
At some point I came across Carl Bugeja\'s very interesting experiment with PCB motors, and I began to wonder if I could use the PCB to make a DIY device that would take my larger modules and smaller talp
The mirror assembly will be 3D printed as I originally did, but I hope that the flat PCB magnets and nd magnets that replace the solenoid will make it smaller, lighter and responsive.
Conceptually, the idea is simple.
Like my previous design, the mirror is mounted on a 3D printing platform with integrated hinges.
I know from my previous project that this is completely what a consumer 3D printer can make.
The PCB has a short distance below the platform and can provide four coils.
The two coils diagonally opposite will be connected in series so that when the current flows through them, one will provide the pulling force, while the other will provide the driving force against the 2mm diameter nd magnet above it.
The two opposite coils work together and will rock the hinge platform back and forth on the diagonal.
Two sets of relative coils, each of which is 90 degrees from the other, provide a double
Just like the Axis control in the commercial TALP1000B module.
For this project I know I need as many four coils as I can.
I want wooden boards made in the United States. S. A.
At OSH Park, it means I have to limit myself to four copper layers and 5 miles of trace width.
My goal is to keep the size of the board in 1 square inch so that the cost of 3 boards is about $10.
Later, I had to add a little bit to make the total cost $13 to accommodate a title. 3 boards 80.
Initially, I wanted to design the whole thing in Inkscape.
This is a tool I am familiar with and I know it can be used to draw some curves that look great.
However, after some research, I found that it is not easy to go from the Inkscape layer to the manufactured PCB.
Since this is my first board, I don\'t want to screw it up!
At that time, I had to learn a real PCB layout program!
I have considered Eagle, but the free version is limited to two layers, which is not enough for my project!
While browsing hackaday, I read the Blinky tutorial for KiCAD and realized that it would be perfect.
I finished all the classes except sending the blinky board for manufacturing as I planned a completely different board!
The Blinky tutorial gave me a great start in designing my own motherboard.
All I need for my board is a component, a four-pin, which makes it easy to draw a schematic!
The most difficult thing to design a circuit board is to find out how to place the spiral trajectory correctly so that all PCB layers contribute to the magnetic field.
I also have to find a way to connect two diagonal pairs of coils and head pads in series without crossing marks.
I used the right hand rule of Ann Pei.
All my spiral marks are reversed.
Clockwise, but they alternate from the outside --in to inside-
Every floor has
Placing vias is a challenge so they don\'t miss any of the layers.
Since via runs through all four layers, it is necessary to carefully offset each other and connect only two layers at a time.
Fortunately, once I draw a coil, I can copy it and rotate it to make the other three.
Let the first two pins drive the first coil and the second two pins drive the second one, which will be most natural, but the only way to connect everything is to insert the pins, so, pins 1 and 3 can be connected to a pair of coils, and 2 and 4 are connected to the other pair.
That\'s why the schematic crosses the wires.
Once my design is complete, I can visualize it in 3D using KiCAD\'s visualization feature.
How cool is this?
In the final step, I verified my design using the design rules of OSH Park.
Going into the Blinky tutorial gives me an idea of the whole process, including the necessary design rule changes in KiCAD.
Once I was happy with my design, I created an account on OSH Park and uploaded my KiCAD PCB File with \".
The order page provided me with a good presentation of all layers and let me verify my design for the last time.
Once I submitted the order, OSH Park did a good job of letting me know the status of the order and letting me know when the group (
Including my board and others)
Went to fab when they were ready to mail separately.
If you would like to order some boards yourself, I have included a zip file in the KiCAD documentation.
The design is open source hardware by CC-SA 4. 0.
As I waited for the board to be made, I started designing the 3D printed parts.
I started the design at FreeCAD but found that the design was beyond my FreeCAD skills.
So I moved to OpenSCAD, a tool that I have more experience.
I designed a part that uses a concentric oval shape to make the various parts of the movable universal frame.
I made a small bridge as a hinge and wanted to deposit enough plastic on that bridge to make a flexible hinge.
It was difficult to get a good print, but in the end I got a part that worked as expected. . .
At least in theory!
A few weeks later, I received the board made!
Below is a video of me opening my first custom PCB!
Then I welded a 4-
Pin heads on a piece of board and measure the resistance of each pair of coils.
The result was 31 years old.
7 ohm, half of the 64 Ohm I measured on the TALP1000B terminal.
This resistance means that when connected to 5 v, 157 mA will be drawn for each axis, and a total of 314 mA will be drawn when both axes are powered on.
I\'m not sure how high the current the PCB board can actually handle, so I first connect it to a variable desktop power supply and carefully turn on the voltage while looking at a small 2mm nd magnet on the PCB.
Since I was going to power the board with 5 v, I turned the current up.
I don\'t want to break the board so I\'m not trying to figure out the maximum current it can withstand.
The resistance of the PCB coil turned out to be a lucky accident because that meant I could reuse the drive circuit I used in the TALP1000B experiment.
The circuit consists of Arduino Nano and SparkFun motor driver
Dual TB6612FNG as motor driver.
The current of the motor driver comes from the 5 v pin of the Arduino Nano, which can provide 500 mA when powered by a USB connector.
So this is enough to power the PCB coil without any modifications!
Unfortunately, my first attempt to do the laser steering module disappointed me.
The appeal and rejection are very weak and too weak for my original flexible hinge design.
After going through some changes, I decided to use the spiral hinge, which is flexible enough to do some movement.
This is still not enough for acceptable performance.
The original trick was to stack the pcb to increase the magnetic force!
A single PCB is not enough to drive the laser.
But when you order from the park of Oz, you get three identical pcb.
It turns out that these PCBs can be stacked in order to increase the number of laps per coil and more magnetic force!
By using a super long joint, you can weld two or three pcb at the same time.
This will connect the coil in parallel so you can still drive it using 5 v, but the current per pair of coils will increase from 150 mA to 450 mA.
You can no longer drive the circuit from the computer USB port, but a phone charger rated at least 1A can do that.
To stack the pcb, you need to: first, make the stack of three pcb with prototype
The board at the bottom.
Insert the long edge of the title through all four plates, so that the pointed teeth appear through the prototype plate at the bottom.
The original plate will serve as spacers, enabling us to push the plastic Bridge to the correct height.
Place the teeth on a hard surface and push the plastic Bridge down from the top to make it flush with the top PCB board.
Now when you remove the prototype plate from the other side, tines will highlight the right amount of welding.
Since the PCB stack is several millimeters thick, welding is unlikely to be the correct Wick throughout the process.
To ensure good contact, I weld a piece of plate at a time, but during the welding process I had to use the off-weld iron.
I started with the first PCB.
Solder climbs up the head pin, so it is not possible to flush the second board with the first.
I found that by using my solder strip I was able to absorb the excess solder and leave enough solder to come in contact so that the second plate could be placed flat on the first plate.
I repeated it, then welded on the second PCB, and then again sucked out the excess using the off-weld iron.
On the last board, I used the extra solder to get it to the wick throughout the stack.
When finished, I bend the pins with pliers and let them stick to the side!
With a three-layer PCB, the module is powerful and can handle the laser well.
This is a lot better than my original solenoid.
DIY Laser steering module-
It\'s smaller, lighter and less distorted!
What I\'m trying to say is that it performs the same as the commercial TALP1000B, but it works with a purple laser in addition to being stronger and easier to manufacture, which allows for light emissionin-the-
Dark screen for projection!
The sketch of the SimpleDriver Arduino can draw a circle, using floating point numbers for the heart or the Lorenzo\'s attractor (
To change the shape, edit line 563.
Also uncomment 581 lines for Lorenzo appeal to enable autoscaling).
LineDrawing sketch is an experiment of drawing lines using Bresenham\'s line algorithm.
In principle, it should allow drawing lines with less vibration, but I think I need a PWM microprocessor with a higher resolution to really work (
I am currently waiting for a blue pill to go through further experiments! ).
Although there is only one PCB, but the performance is not enough, stacking these three PCB, gave me a 5 v laser steering module, which is equivalent to the TALP1000B, cheap and easy to manufacture, much better than my original solenoid version!
It is thinner, lighter and more functional than my original solenoid-based DIY Laser steering module.
Although I have been here for more than a year, it is a good learning experience and I am satisfied with the results!