Active Stabilization Rocket System

I would love to thank OSHPark for getting my boards very quickly and for very cheap. They look wonderful, and I cannot wait to use them. I cannot recommend them enough for their prices and the nice looking Purple PCB. I am greatly happy with them and look forward to getting Version 2 made soon.
(I made minor errors on Version 1. The Servo pinout is not correct, and the clearance is a bit off between the sensor and microcontroller boards.)

In other news, I finished debugging the abort system this morning while I was waiting to get the boards in the mail. It now works flawlessly and efficiently. With that abort code is done, my stabilization code is finished and all I have to do is calibration and flight readiness checks. I am rapidly completing this project and hope to have the entire thing launching by December.

On the note of Fins:
I am working my hardest to get the money to order fins for my rocket and should have the money for that shortly. Once I order those, I will have every part of my rocket complete and ready to go.

Godspeed,

-Jeremy Hall

This week has been filled with a whole lot of measuring and designing and ordering. As you know, I got my PCB ordered. I also continued on to get my nose cone for the Rocket ordered. I managed to get it for cheap (about 15 dollars total) and it will be coming in Tuesday. I also managed to order myself the Epoxy needed to put this all together. That was the last of the money I had for the month. I am looking into ways to continue to get the 40 dollars I need to get fins laser cut and shipped to me.
I also realized I had a error on my PCB. It is not a major problem and just means I have to change the pins of my Servos which is not a big deal at all. I switched the power and ground signals on it and, I just have to move the wires in the molex connectors. I also got my newest sensor module, it is the same one I have been using for the prototype testing, but unfortunately I lost that one so I had to order another. I also ordered myself 400 male pins for my PCB so I can solder it on when it comes in (Hopefully soon.)

Last night, I started designing the circuit board for Version 2 of my Rocket Control Board. It is now using a 32 bit microcontroller used in the Uno and the M0 Feather that Adafruit sells. It is a more complicated design, and I am adding microSD card support onboard, also I am adding Lipoly Charging and probably will have a USB connection for debugging. Stay tuned for that.

Godspeed

-Jeremy Hall

I spent all of yesterday and most of this morning working on my first actual version that I have ordered from OSHPark. This is about my 3rd time designing this board and it came out wonderful and has became very small. Here are some images:

This is much smaller and more compact and I will probably be using this in my first launch if all goes well.

I will be uploading the schematics and board files to Github today and heres a link to the project on OSHPark if you want to order when I confirm they work properly. Order

Later today and tomorrow I will be designing the fins for this rocket and will probably be ordering them tomorrow.

Godspeed
-Jeremy Hall

(Shoutout to OSHpark because they are awesome)

(Edit: Forgot links)

I just uploaded my Version 1.9 of the Rocket Stabilization System code to Github! With this there are many changes

• Cleaned Up Code
• Abort! conditions
• Full Data-logging capabilities
• More customization options
• More functions!
• More rocket science!

All code is available on Github!

After a two more days of work I have finished code to get the BMP180 up and running and so far It seems to be pretty accurate (+-1m). I also took the chance and added SD logging functionality to the program so it can record telemetry on the way up.

As always code is on Github.

Godspeed!

Ever since I got my parts, I have been focused on getting it running. At first, I tried with a PID controller because that seemed like the most straightforward thing to do. Unfortunately, I was looking at it all wrong.

I looked at PID control theory and studied it as much as I could, but for some reason, I could not get it as near as stable as I would like. It just wouldn't want to go to the middle position unless it was 100% perfectly at 0. This makes sense because this is what PID controllers are designed to do. Unfortunately for a rocket, this type of movement would cause for crazy oscillations throughout the flight even with tuning of the controller. What I needed was a direct linear relationship between the Yaw, Pitch, and Roll and the rocket.

Yesterday, I started looking around and seeing what other people have done and saw this in common with the two people I looked at; they used the map function to map the gyro values directly to their control systems.

I thought to myself, "Woah, hold on here... This is too simple, this is suppose to be hard right?". I looked and I thought and I debated with myself on using this. I ran the tests, and it performed brilliantly. I no longer had to use a PID controller which will make the control system considerably faster and would be more responsive. It worked.

It works.

(Code is on Github.)

Through this busy time I have been working on getting some parts for the first prototype of the rocket. I ordered myself a 98mm (4") body tube and a 29mm motor mount for it. It has finally came in, along with these parts I have finished the basic code that I need to test with these parts. I will be posting the code once I get some final bugs with the roll figured out. Everything is going well for a test launch later this year or early next year.

(On another note, I am working on some safety systems for the rocket since it will be a mid-powered rocket and can pose some dangers with the system on the first few launches)

I took the opportunity last night and this morning to go through and design myself a circuit board based on all the pin-outs of my components like my microSD card to SPI board and my GY-87 10DOF board and fit it with my pro-mini that I will be using.

Once I finalize my board design I will post both the board and schematic files here!

Currently this is my design for the circuit board:

On another note: I have published my filtering code on Github!

-Have a nice day!

It's been a while since I posted an update, so here I go with a huge one.

Over the last few weeks, I have experimented with different kinds of filtering and I strayed away from Kalman filtering entirely. I have decided on using a Madgwick or Mahony Filter instead. The great news in this, through these many weeks I have worked hard and I finally got stable output using Madgwick and Mahony filtering. It took a lot of work to get it working without a single library other than the Arduino Wire library. It works great! Also, it seems to be running around 200 times a second, which I believe will be more than enough for what I need. My next step is to implement a PID control based on those 3 axes and the error that it strays away from perfect flight. Godspeed.

(I will be posting code on Github soon)

Log 1: Got a Basic Output using a Kalman filter, 10dof sensor should be coming in today. Will be posting code when done.