Projects
December 2022
FPV Drone
For Christmas I got some parts for a drone. Carbon fiber frame, motors, ESC, flight controller, and even a visual transmitter and headset.
I set to work assembling, and configured it in betaflight. Getting my flysky fs-ia6b reciever to work with the flight controller was sort of difficult. Most drone transmitters use ELRS protocal yet mine was designed for helicopters and airplanes so I had to configure IBUS protocal in betaflight.
It didn't take long for me to finish but configuring the visual transmitter was also sort of difficult. The default channel's and bands provided a crappy video stream so I had to go through the channels of the visual transmitter on the datasheet until I found one the synced up well with my headset.
After a few days, I decided I wanted to get some good footage, so I 3d printed a mount that perfectly screwed into the frame of the quad. I designed it to house my old $30 gopro knockoff that I am using before I use the nice one that can record in 4k. It is able to change the angle, downwards for more photagraphy and upwards for more faster paced racing.
The problem after filming a bit was that the drone was super hard to keep steady. It was really difficult to keep it in place, and now I have gone down the rabbit hole of gps assisted drones. Anyway, betaflight is good for FPV racing so I can configure my drone easily with that, but when I want to do more cinematic shots, I will try to start using iNav to configure my drone. I will also need to add gps and I already have a magnometer built in so it shouldn't be too terribly difficult to configure autonomous flight, or something similar.
I would also like to comment on how well the drone camera worked, and the M3 nut perfectly press fit so the entire setup is super clean.
I also started a new YouTube channel to start documenting my progress on the drone.
November 2022
thrust vector control gimbal
This is the finished design for the thrust vector control (TVC) gimbal for my rocket. This will allow me to gimbal the rocket motor for stabilization and other flight control characteristics rather than using fins. I will be using a reloadable D or E class motor that I have made with a custom fuel grain for a longer burn time.
There are two major parts to this gimbal. First, it is entirely 3D printed so I will need some kind of liner for the motor to prevent melting. Also the rails are slightly thin for a larger range of motion, sacrificing a little bit more rigidity unfortunately. The gimbal also has modified servos. The flight computer uses 7.4v to power everything, including the servos. Luckily, I had some 7.4v tolerant servos. The problem was that there are plastic gears and those are prone to stripping with higher loads, so I had to modify the servo with some metal gears from another servo.
Now I have a gimbal fitted into the rocket that is functional and controllable with my flight computer.
October 2022
first reloadable apcp rocket engine
The #1 priority was keeping everything safe so I had cinder blocks around the engine to make sure no shrapnel would go anywhere (except up I guess), and the entire area was hosed down to prevent fires. I also had a hose on standby which I promptly used right after the motor burned out.
The goal here was to test the reloadable nozzle that I build that is screwed into place and has 2 O rings as shown in the model. Problem was I made the nozzle smaller than the previous version which had too long of a burn time and the thrust was too low.
I also changed may APCP composition to have less aluminum and more ammonium perchlorate. This made the burn much quicker and the rocket got to a much higher chamber pressure and ended up blowing out the side.
Now to the good news, the removable endcap worked. Nothing leaked through and it contained the pressure. There is the slight issue of the concrete endcap being hard to remove. To fix this, I am building my own lathe to custom machine a graphite endcap, as well as a possible graphite nozzle. Concrete is heavy and chunks can break off easily and graphite is much lighter and temperature resistant. Another pro to the graphite endcap is that graphite can also double as a lubricant so it would be slightly easier to slide in and out of the casing.
To fix the blowing out the side issue, I will most likely be switching to end burning fuel grains to have a longer burn time for the TVC rocket. I will also switch to using a titanium casing which will hold up much better and will be almost as light. Hopefully, I will still be able to switch to core burning fuel grains for higher thrust and lower burn duration rocket motors.
Unfortunately my external battery for igniting the motor was dead, so I tried to power it all using the power supply that I made. The high current draw from the nichrome wire tripped the arduino and the arduino reset itself so it unfortunately did not log the data of the motor (sorry!). Next test I will for sure have that data and hopefully a motor that will hold together.
September 2022
(almost) Finished flight computer
I have finally completed my flight computer!
After 3 iterations, I have finally completed a flight computer that has the right specs for what I need.
The first one had a problem with not having enough program storage so I wasn't actually able to program anything other than LEDs blinking... So I bought a slightly more expensive PIC microcontroller, the PIC18F27J13, which has 16x more program memory.
The second one had a slight problem with being a little cluttery but it was still cleaner than the orginal, but I did not have anything to switch the flight computer between program and run mode. This meant that I had to short two wires and that ain't gonna cut it.
In the end I made my 3rd iteration which is now SUPER clean and moderately symmetrical so I can sleep at night. There are now also two switches, one for turning on the board and the other which allows me to switch between program and run mode. So far I have been able to blink LEDs, send PWM signals, control servo motors and write data to an SD card. The flight computer now has 2 MOSFETs for pyro channels in case I want to propulsevly land in the future, as well as 3 servo ports, one for parachutes and 2 for the TVC mount. There is also a 6 axis gyroscope and accelerometer as well as a barometric pressure sensor. Version 1.4 coming soon with a better IMU that has lower drift figures and easier to work with.
September 2022
diy hho generator
Taking a little break from rockets for this fun project. I've tried in the past to make an HHO generator but never exactly found a suitable design.
This take on the HHO generator is much cheaper, easier to build, and compact than previous designs but I still feel like there are a few leaks that I haven't found yet. Also my homemade little power supply unfortunately does not go more than 5 amps which hinders the process a little but it still works.
August 2022
first flight computer
This is the first iteration of my flight computer! I've wanted to build a thrust vector control rocket for a while but have only been working on the rocket motors so far.
This flight computer has most of the things I need, but I don't really understand some of the systems yet. This is my first actual PCB and not just some connections with an arduino on top. I had to copy one of the micro sd card modules that is used for an arduino and I feel like some of the things are unnecessary but I am too scared to remove them, lol.
For one, I have a SECOND voltage regulator to step the 7.4v down to 3.3v for the reader... when I am already using 3.3v for everything else so I will probably remove in the next design. Another thing is my routing is not very good. I am definitely going to need to improve that and make it much less messy in my next design.
Overall pretty happy with it so far, all I've got is the LEDs blinking but I'm sure I will keep with the updates as I continue with this board.
June 2022
DIY hot plate soldering
It's been awhile! I have been working all summer to try and pay for my future projects 🙂
I recently designed a flight computer and needed a way to solder the SMD components! Problem is I don't have a spare toaster oven to make a reflow oven, nor do I have an iron (like the clothe dewrinkling type) to make a hot plate. This hot plate is my solution which I was able to make with $0.40 worth of components.
The process is easy. First we have the hot plate. The hot plate is just a piece of scrap metal with a piece of nichrome wire running through. The scrap metal has a little bit of paint so that it doesn't short the power supply. For power I use the desktop power supply that I made a while back. I found 11.1 volts would keep it at a pretty steady temperature that works for most components.
I reccomend not doing it on a piece of cardboard like I have right here, but instead doing it on like a coaster or some kind of ceramic plate which is what I do now.
April 2022
First APCP rocket engine
First ammonium perchlorate composite rocket motor!
This thing kind of sucked. I think the concentration of Aluminum was much too high. This is evident in the massive amount of sparks coming out of the motor. Composition was 70% 200 micron ammonium perchlorate, 10% aluminum, 20% epoxy resin for the binder. I could have used more AP as the burn rate was relatively low and I definately could've made a tighter throat for the nozzle as this one was too wide and there was very little thrust being produced.
Peak Thrust: 1.15 Newtons
Total Impulse: 8.062
Specific Impulse: 16.4362895
Numbers might be off as it was weird doing the calculations for this particular motor.
January 2022
liquid bipropellant fuel injector test
Eventually I would like to work on liquid rocket engines, so I decided to try and make myself a pintle injector. Unfortunately I do not have the means to machine such a complex part out of a more heat resistant material so I had to test with 3D printed plastic. The test I did uses propane as the fuel and compressed air as the oxidizer. These are both gases I know not liquids but I am working on a turbopump or maybe just an electric pump that will pressurize the liquid fuel for me. The propane fuel would go out of the 3 small holes into the air stream and would collide, atomizing it and creating a fairly clean burn. In the video, I had to hold a torch up to the stream of fuel/air to keep it ignited and I couldn't do too much air through or it would blow out the flame. Realistically, in a chamber, this would make sure the fuel stays ignited but would also melt a plastic injector.
May 2017
air cannon build
I decided to build an air cannon!
I saw a youtube video making a potato cannon so I wanted to do something similar but a little lower powered. This sucker runs on compressed air and is suitable for launching things like nerf darts. TIP: put nails through the nerf dart for it to be a little more lethal 🙂 Do not use against humans, or living things for that matter.
Anyway, I didn't find a tutorial on an easy to make air cannon so I made one! It cost me about $40 and was worth every penny. I pressurized mine to about 40 psi but have gone to 60 psi. Nerf darts at 10 psi leave welts FYI so maybe don't shoot at other people at higher pressures.