3D Printed Tvc Rocket

Welcome, ladies and gentlemen, this is

How to Build a 3D PRINTED TVC ROCKET

(P.S. This is a prototype and has not flown and is for educational purposes)

We are using a Raspberry Pi PICO 2 W paired with a BMP 180 Barometer and an MPU 6050 gyro and accelerometer, which, when used together, have many potentials which we use to make a TVC rocket, TVC stands for Thrust Vector Control. In rocketry, this is used for stabilising a rocket without fins by gimbaling the thrust. Many real rockets use this, like SpaceX's Starship or Artemis 2, which is going to launch soon. We get values from the gyro and put them into a PID controller. We'll talk more about the PID controller in the Coding section. The airframe is just a 74-76mm diameter cardboard tube, which could catch fire, but shouldn't if you don't have an ejection charge on your rocket motor. The motor used is an E-12-0. E is the class, 12 is the average impulse, and 0 is the delay for the ejection charge. 0 means no ejection charge.

Without further ado, let's start.

Tools

1. 3D printer
2. Basic set of pliers
3. a Small craft Knife
4. Drill
5. Drill bits
6. servo tester
7. Some form of glue
8. Computer with Thonny

Supplies

1. 24x M3 bolts and nuts (doesn't matter what type of head)
2. Pico 2 w
3. MPU 6050
4. BMP 180
5. jumper wires
6. Bread board
7. 74-76mm diameter cardboard tube
8. Black spray paint
9. 2x Pen spring
10. 3x servo extenders

3D printed Parts

1. 1x Top connector
2. 1x Bottom connector with tabs
3. 1x inner gimbal
4. 1x outer gimbal
5. 2x servo horn 15mm
6. 2x connecter bar 25mm
7. 1x motor shroud 24X95
8. 1x avionics bay
9. 1x Nosecone One
10. 1x Nosecone Two

Firstly, we need to make this tube look a bit better. Find a well-ventilated area and hang the tube up somewhere. Get the black spray paint and lightly spray over the tube till black don't overspray the tube; otherwise, it will drip. When dry, do another coat if need be.

Fit the motor shroud into the inner gimbal screw together with two M3 scews then fit that assembly into the outer gimbal piece and fit with two screws again. Make sure the gimbal can move easily, but won't unscrew in-flight. Once you have your gimbal, we need to attach our servos. Your servos should come with a set of screws. Get the two bigger ones and screw the servos in the correct position, as shown in the photos. You may need to thread the servo's cable through a hole if you've oriented it correctly. Last bit, get a servo tester and set both servos to 90 degrees. Once you've done that, get the servo horns, the 3d printed ones, and the connectors and connect them together with a screw. Then, screw the end of the connector to the motor shroud and the other one to the inner gimbal. When the gimbal looks straight, and the servos are straight, connect the horn to the servo with some small screws(they should be provided with your servos).

To get the holes into the best position, measure 1 cm up and both ends of the tube, and make four marks on each end in a square pattern around the tube. Once marked, drill with a 2mm or 1mm drill bit. This should make the M3 bolt snug. Drill the top parachute fairing holes and the gimbal holes. Go up a bit from the gimbal holes and drill holes for the Avionics bay. You can use it as a guide for where to drill, but if not, drill four holes around the tube at least 70mm above the TVC gimbal holes. Then, once the first set of holes is drilled, measure 115mm up.

Next, we are going to cut the tube to fit the TVC mount. We need to do this, otherwise it won't fit when it's moving. Fit the tvc mount into the tube and screw it in on one side of the tube with the M3 bolts and hole we just did. Don't do them too tightly because we're new to undoing them later. Once its final orientation is set, we are going to acuwat the servo around and see if it hits the side or where it hits the side. When you've got an idea, you can make a small cut around the part where it hits best. It's best to cut it into a square becuse it works better that way.

Now that we've cut the tube and made the TVC mount, the next thing to do is make the parachute fairing. first find Nosecone One and find where to put your Servo shown in the photos next work out what way your servos move if its left set servo to 0 and put servo horn up if right set to 90 and put the servo horn on up. Next we need to insert the springs find 2 long to to long and very springy, the springer the better. Put a blob of glue on the end and put it in the hole.

Next, we're going to test the electronics. First, get the breadboard and wire the BMP 180, the MPU 6050, servos and the Buzzer if you want, according to this picture. Remember Gnd goes to Gnd, and check your power you are inputting into the MPU 3.3v NOT 5v.

Next, get the breadboard we just assembled and unplug the servos. Peel the adhesive on the back of the board and stick it on the Avinoics bay. Strap a 9V or any other sort of battery on the back with zip ties and wire it up accordingly through some sort of resistor. You can use a 3.9kΩ resistor in series with the 9V.

Next, we need a computer with Thonny. Get the Pico and plug it into the computer, and upload the code from the downloads. This is just a Test code for a successful TVC rocket. You're going to need to write your own code. This code uses something called a PID controller. If you want to learn more, watch https://www.youtube.com/watch?v=sFqFrmMJ-sg or https://www.youtube.com/watch?v=4cw9K9yuIyU. Thanks, Joe.

Next, we are going to assemble the whole thing. Get the TVC Gimbal and put on a servo extender on each servo lead, then fit the TVC Gimbal into the side of the tube that has a hole in it. Remember to turn the gimbal until the connector that's going to poke out is in the correct position, then get the Top connector 3d piece not to be cofused with the conecter on the gimbal and fit it in with the hexagonal bits facing out once everything's aligned and ready to go, bolt it all in with four M3 bolts in the holes, Bottom assembly done. Good job, go have a drink, maybe some coffee. Next, attach the Gimbals servos plugs to the Avionics bay breadboard. Remember, this Avionics Bay isn't flight-worthy. Slide the Avionics Bay into the Tube and bolt it in with the hole we made. Next, glue in any way, Hot Glue seems to work ok, the bolts for the parachute fairing, remember these are M3, then connect the parachute servo to the avionics bay. It's recommended to use an extension cable for easier access, but you don't have to; then plop it on top and bolt it in. Your done ദ്ദി◝ ⩊ ◜.ᐟ

This is easy, just get the motor, stick an ingitor in with the bulb facing inwards and stick a plug provided in there are some pictures to help with this process. Next, just slot the motor into the gimbal, and you're done.

By soldering the avionics bay wires, this is a fully functioning rocket.