Requirements
My final project will be a rotatable pan-tilt camera. I will attempt to make it as similar to what it is based on, a gadget from a game called "Rainbow Six Siege". in the game, the "operators" can pull out their phone, and then go on camera to look around. While on their phone, they can move this camera to look in any direction horizontally and around 120 degrees vertically. Additionally, this camera specifically can open the black panel on the front, in order to give the camera an undistorted view. If you go to the 3d model above, and look near the bottom of its box, and change the static pose to moving pose, you can see exactly how it moves in game, and how I want it to move. I also want to keep this working after fab, and put it in my room somewhere, so it has to work well enough to make it out of fab academy alive.
I used this as a reference, its liscense does allow me to modify it with attribute, so my design was based on the one above, which can be found here
Sketch
This sketch outlines the major electronic components of the camera. In order for it to be able to rotate infinitely along its base, it needs to have no wires connecting the base and the head, or a slip ring. When I was researching it, while a slipring seemed interesting, I have more experience with batteries and decided to go the disconnected route. It would probably be more reliable or at least easy to replace an old battery than a broken slip ring. I also have some experience with stepper motors when experimenting with making a gantry for them, so I decided to go with a thin stepper for the one connecting the head to the rotatable base, and a larger one connecting the rotatable base to the unmoving base. All the logic will be run through either a Seeed xiao esp32-s3 sense for the camera, or my own custom esp32-c3 board. I plan on redesigning the board for the fourth time specifically for this. This means I will target compactness, removing the usb-c port i added, and breaking out around 8 pins total for the board. 2 usb datalines that will be soldered directly on, 2 will be power and ground, and 4 will be for the stepper.
3D design
First pass
As part of cad week. I designed the 3d portion of my final project. To give a basic overview, I used one sketch per part, with 3 separate parts that I called the unmoving base, the moving base, and the head. both base pieces were not that complicated, and I decided to drop the two levers on the side of the camera so that it would be easier to 3d print it, which is how im planning on making it. in planning on 3d printing it, I had to make sure that a quadrant of it could fit on a bambu a1 build plate, which are the 3d printers my lab has. Besides that, however, I did not design it for being 3d printed in parts, and therefore will have to go back edit it later. This isn't the end of the world, as Fusion 360's parametric modeling feature makes it very easy to essentially time travel to an earlier version of the design, and any changes made in that version will cascade to the current version. Again, for more information, please check my documentation as part of cad week
Internal Electronics
Camera in Stepper control Camera view out
Camera
I found that the (seeed xiao esp32-s3 sense)[https://www.seeedstudio.com/XIAO-ESP32S3-Sense-p-5639.html] was my best bet at both wifi and camera support. In getting the camera working, I followed this tutorial by the seeed studio team, and it worked flawlessly. However, I found that although the camera worked, adding a joystick onto the same page would be very hard. in troubleshooting this, I found that the video stream used a motion jpeg, basically just a bunch of pictures being sent fast enough to become a video. I also found that it got these pictures through a request to 6.6.6.6/stream, with the ip address being the one of the microcontroller and not 6.6.6.6. Im pretty certain that I will be able to combine the joystick and the camera by making my own webpage, and plan on getting that done next week, during 3d printing and scanning week, which I heard was a bit easier
Networking
Since I needed 2 steppers, I didn't just need connection from the phone to the stepper, but some way to communicate between the microcontrollers. For this, I discovered MDNS, which is essentially is a custom dns server that can run locally, so that instead of typing 192.168.4.1 to connect to the esp, I could type maestro.local. MDNS is very easy to set up, requiring just the line MDNS.begin( name of network), and then name of network.local can connect to it. Once I had communication between the two esp32-c3. After getting that working, I needed to figure out how I wanted to send data between the two. I decided on using html forms, which is essentially the same thing that your browser uses when communicating with a simple website. When combining this together, it worked nearly flawlessly, with the exception of an error I had for 2 hours straight, of me trying to ping the webserver using maestro.local instead of maestro. for some reason, when using mdns the way to connect to another server is to drop the .local on the end of it, and that issue caused 2 hours of hair pulling.
Steppers
As for the stepper control, I was unaware of any pre-made solution for it, so I had to make it myself. I decided on using my custom board to control it, as I planned on designing a custom board later, for whatever fab academy week that requires custom boards, that would fit to the base of the stepper or similar. In using the stepper, I decided on the A4988 driver as I had used it in the past on a project that reached nowhere near completion. While the a4988 highly suggested a voltage of at least 8v, I found that 5v from my battery packs worked fine, with only a loss of a bit of torque, which I hope won't come back to bite me. Using the stepper is very simple, on the microcontroller you just set a pin high or low to show direction, and then pulse it on and off to move it one step, which is about 2 degrees. By combining the work of the networking section and stepper section, I was able to make an interactive joystick webpage that would move the stepper, all run off of the custom esp32-c3 board.
As of the end of week 4, my code was in 3 separate files, for each microcontroller, and can be found here
Refining 3d Design
after getting the code working, for 3d printing and scanning week, I went back to work on the design. for my design in 3d printing and scanning week, I wanted to use a scaled down version of my final and make it print in place, but also used that as an excuse to fix some bad designs, like the head, which I completely redesigned to make it more like the reference.
PCB design & Manufacturing
This is a general outline of what I made, the making of can be found on my week 10 page For my final project, I needed to make a pcb. I decided on making the pcb in multiple separate parts
The Learning moment: Battery
The battery board was the one I used to learn how to etch boards. setting that aside, the actual board design was a tp4057, basically the older brother of the widely popular tp4056. I would of used a tp4056 if I could of found one, but the 4057 was available on digikey and the 4056 wasn't.
PCB Etching
I was entirely new to PCB etching starting on the battery. I started by looking online, where I found this youtube tutorial for general use and this tutorial with a promising process to speed up etching using a sponge. I started with a simple sharpie and a smiley face, which came out well and proved that my ferric chloride actually worked. It also proved the sponge method was really strong, as it took around 1-2 minutes to etch that face
Getting Complicated with Etching
After proving the effectiveness of my ferric chloride and the sponge method, I started to work to figure out how I could make a board without using a lot of materials. For this, I discovered that my previous making of a solder stencil with pencil could translate really well here. After alot of testing, outlined in my week 10 documentation, I found that kapton tape was easy to laser cut and was thin enough to not get easily ripped off when rubbing with a sponge. Through that, I was able to laser cut the negative of the boards f.cu, which then allowed me to etch away everything but the traces and pads, giving me the result pictured
The most unconventional: Stepper Driver
Because of the fact that im using a stepper motor combined with battery power, I needed a driver that was able to work with less than 8v, which is the standard for the drv8825 and a4988. I found that the drv8835, which is nothing like the 25 even though it sounds similar, would work for me. the main reason for using it was that low voltage, as it works with 2-12v, but it also features 1.5A max current, and a price of only 50 cents. Combined with the 3 filtering capacitors it needs, and the board, the entire driver cost only 2-3$. The unconventional part was the shape of it, as I designed it to be soldered directly to both the stepper through identifying the molex connector on mine (JST-XH), and then used pads to allow it to connect to the microcontroller "wirelessly" (its soldered directly on).
The most crowded: Microcontroller
Because of the fact that im using a esp32-c3 wroom module, and not a Xiao module like most of my classmates, I needed to have much more components on the side. I ended up with 6 resistors, capacitors, or voltage regulators on the main board. This board roughly followed the layout of my custom board I built before fab, but removed most pin headers and reformatted for single sided board. It also was designed to be milled, but I milled it, didn't get it working (due to coding issues with the stepper driver), but when resoldering it since I thought it might of been the voltage regulator, I ripped a trace and didn't have a backup. I just soldered one of the ones I ordered (I ordered all 4 boards in week 10 as a backup)
The smallest: USB-C
this is kind of a continuation of the microcontroller, but I needed a usb-c module to communicate between the microcontroller and a computer. I decided to make it a separate board since the microcontroller had the potential to be made through milling/etching, and the USB-C port I used in my other boards is way too small to have a chance of being milled/etched successfully. using USB without all the fancy gimmicks (just usb 2.0) is very easy, as its just 2 resistors soldered between the cc pins and ground.
Manufacturing
Etching
As I described above, I used etching to successfully make the battery board, which I described in much more detail in this section of week 10
Milling
I used milling for my first version of the microcontroller board, which was outlined in this section of week 10. Of all the processes, this was the most annoying as unlike etching, where if it failed it was very obvious, milling usually failed during soldering, which made me not trust the board and end up using a ordered board
Ordering
I used ordering for my first version of all the boards working together (except the battery). I outlined how to order in week8 for the group work, and the specifics for my final in week10.
PCB making hero shot
Midterm Review
As part of the midterm, I needed to figure out how I would get this done.
What still needs to be done and when
listed in order of importance, and also when I plan on doing them
- in molding and casting week, make the curved front see through panel
- in any of the weeks, finish the 3d design, and print it. This is high priority but will take a long time spread out
- in interface week, finish making the webserver, focusing on figuring out how to use that library that allows for an easy stream from the camera with actually good performance
- In integration week, work on hiding wires/fixing issues where needed
How I could do those
- For the mold, its just going to be learning how to in the week, and then either making it as the main goal of that week or using what I learned
- for the 3d design, I found really powerful plugin during machine week called gf gear generator, and used it there. Gears were an issue for me before, but with that plugin, I should be able to easily make gears.
- for the interface, I have each working separately, this will not take long at all
- Integration depends on everything else, as its the last step of the operation. Im planning on leaving a lot of time for it, and in general getting my final project done 4-2 weeks early
Tentative Gantt Chart
this gantt chart gives me A LOT of time before the final project is actually due, and this is the outline I plan to follow. Im leaving all the time at the end as im expecting to run into multiple hiccups, and don't want to procrastinate and run into those hiccups in the week that the project is due.
| Part | Quantity | Total Price (USD) | Listing Price | Note | Note COMBINED |
|---|---|---|---|---|---|
| Stepper Motor | 2 | 12.14 | 7.06 | https://a.co/d/5kIdjjb | |
| Servo | 1 | 27.99 | https://a.co/d/gGgNJGU | Comes in a 4 pack, only 1 needed, incredibly common though so check storage | |
| 1Kg 3d filament | 1 | 19.99 | 19.99 | https://us.store.bambulab.com/products/petg-hf | |
| Stepper Driver PCB | 7.70 | For the custom driver, 2 are used | |||
| --- Driver Chip | 2 | 1.55 | https://www.digikey.com/en/products/detail/texas-instruments/DRV8835DSSR/3088201 | 1 per board | |
| --- 1206 10uF capacitor | 2 | 0.14 | https://www.digikey.com/en/products/detail/samsung-electro-mechanics/CL31A106MBHNNNE/5961220 | 1 per board, common capacitor size, order in bulk for large savings and later use | |
| --- 1206 0.1uF capacitor | 2 | 0.16 | https://www.digikey.com/en/products/detail/kemet/C1206C104K5RACTU/411248 | 2 per board, common capacitor size, order in bulk for large savings and later use | |
| --- PCB | 2 | 2.00 | probably impossible to mill/etch, order it, price based on JLCPCB, shipping excluded, comes in a pack of 5 | 1 per board | |
| Battery Charger PCB | 1.01 | ||||
| --- Battery Chip | 1 | 0.17 | https://www.digikey.com/en/products/detail/evvo/TP4057/22482076 | 1 per board | |
| --- 1206 10uF capacitor | 1 | 0.14 | https://www.digikey.com/en/products/detail/samsung-electro-mechanics/CL31A106MBHNNNE/5961220 | 1 per board, common capacitor size, order in bulk for large savings and later use | |
| --- 1206 470 ohm resistor | 1 | 0.10 | https://www.digikey.com/en/products/detail/stackpole-electronics-inc/RMCF1206JT470R/1753845 | 1 per board, common resistor size, order in bulk for large savings and later use | |
| --- 1206 10k ohm resistor | 1 | 0.10 | https://www.digikey.com/en/products/detail/stackpole-electronics-inc/RMCF1206ZT0R00/1756906 | 1 per board, common resistor size, order in bulk for large savings and later use | |
| --- 1206 LED | 1 | 0.10 | https://www.digikey.com/en/products/detail/liteon/LTST-C150GKT/269216 | 1 per board, common component, order in bulk for large savings and later use | |
| --- 1206 33k ohm resistor | 1 | 0.10 | https://www.digikey.com/en/products/detail/yageo/RC1206JR-0733KL/729282 | 1 per board | |
| --- 1206 1k ohm resistor | 1 | 0.10 | https://www.digikey.com/en/products/detail/yageo/RC1206FR-071KL/728387 | 1 per board, common resistor size, order in bulk for large savings and later use | |
| --- PCB | 1 | 0.20 | https://a.co/d/8GRjyGRE | Etched for me, can be milled, price of a copper sheet it's size | |
| USB C Module | 1 | 2.98 | |||
| --- USB C plug | 1 | 0.88 | https://www.digikey.com/en/products/detail/gct/USB4105-GF-A/11198441 | 1 per board | |
| --- 1206 5.1k ohm resistor | 2 | 0.10 | https://www.digikey.com/en/products/detail/stackpole-electronics-inc/RMCF1206JT5K10/1753850 | 2 per board, common resistor size, order in bulk for large savings and later use | |
| --- PCB | 1 | 2.00 | impossible to mill etch, order it, price based on JLCPCB, shipping excluded, comes in a pack of 5 | 1 per board | |
| Microcontroller | 1 | 4.57 | |||
| --- esp32-c3-wroom-02 | 1 | 3.58 | https://www.digikey.com/en/products/detail/espressif-systems/ESP32-C3-WROOM-02-N4/14553031 | 1 per board, it was 1.8$, im almost certain espressif raised prices due to tarrifs, so might go back down | |
| --- 1206 10k ohm resistor | 2 | 0.10 | https://www.digikey.com/en/products/detail/stackpole-electronics-inc/RMCF1206ZT0R00/1756906 | 2 per board, common resistor size, order in bulk for large savings and later use | |
| --- 1206 0.1uF capacitor | 2 | 0.14 | https://www.digikey.com/en/products/detail/samsung-electro-mechanics/CL31A106MBHNNNE/5961220 | 2 per board, common capacitor size, order in bulk for large savings and later use | |
| --- 3.3v regulator | 1 | 0.55 | https://www.digikey.com/en/products/detail/diodes-incorporated/AP2112K-3-3TRG1/4470746 | 1 per board, Really good regulator, I would suggest buying in bulk and using for other projects | |
| --- PCB | 1 | 0.20 | https://a.co/d/8GRjyGR | Milled this one, price is for a piece of copper the size of it | |
| COMBINED | 50.39 |