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

Battery Charger

https://github.com/alltheworld/tp4057 https://www.digikey.com/en/products/detail/evvo/TP4057/22482076 battery charger

Stepper driver

https://www.digikey.com/en/products/detail/texas-instruments/DRV8835DSSR/3088201 another potential motor driver, would reduce need for the boost convert to zilch, looks good 1. cheap 2. high enough current (1.5A) 3. easy (look at the image of a working board, like 6 components on that, looking good)

https://components101.com/sites/default/files/component_datasheet/A4988%20Stepper%20Motor%20Driver%20Module.pdf

Boost converter (if needed if not delete this please remember please)

https://www.digikey.com/en/products/detail/stmicroelectronics/MC34063ABD-TR/1038906 boost converter (if needed)

https://www.digikey.com/en/products/detail/mcc-micro-commercial-components/SM5817PL-TP/1793251