Talon I

Talon I is a 6in rocket designed for the 2023 Spaceport America Cup. The rocket is our second attempt in designing and launching a 6in rocket.

This rocket will stand just short of 8 and 1/2 feet with a 6-inch diameter. The fins of this build will be 5 and 1/2 inches. "Talon I" is the heaviest rocket built by the club, weighing 50.2 pounds for the liftoff weight. This weight includes an 8.9-pound payload and 20.20 pounds of propellant. The rocket will use its payload to gather data on vibration and magnetic fields for future rockets with the goal of self-stabilization. This payload will also record video during flight.

The rocket will be mostly purchased items, except the fins, avionics bay, and payload structures. These separate structures will be student-fabricated and created custom for the rocket. The fins will be fiberglass with an additional carbon fiber layup for added strength. The avionics bay will combine laser-cut plywood and fiberglass for the bulkheads, sled, and coupling. The payload structure will contain ABS mounts and a combination of MDF and stainless steel for the frame.

"Talon I" is a single-stage rocket flying on the AeroTech M2000R. Using this, we gain a thrust-weight ratio of 8:1 and a rail departure velocity of 101 feet/second. This rocket will reach a maximum velocity of 1,207 feet/sec, making it the second-fastest rocket the club has built. The target apogee for "Talon I" is 10,000 feet, with calculations showing a predicted apogee of 10,200 feet.

Structure

Talon 1 will feature a fiberglass body and carbon fiber-reinforced fins. Using COTS parts and 3D printed guides, the building process for Talon 1 will flow smoothly. First, the body tubes will be cut to length with a leveled Miter Saw. The body tubes will be checked thoroughly and ensure they are leveled, if not, rework will be done until leveled. After the body tubes are cut to the desired length, the lower body tube will use a 3D printed “sleeve” that will guide a dremel into making the right length and width fin slots. The body tubes will then undergo prep work which includes a brief sanding/acetone wipe to eliminate excess mold release and ensure efficient epoxying.

The motor mount tube will then be prepared by using 3D-printed centering ring guides that will ensure the centering rings are leveled and attached to the correct offset from the bottom of the tube. A thrust plate will be centered and attached. Once the motor tube assembly is done, it is attached to the lower body tube. Bulkheads will be attached in the body tubes and the couplers will be test fitted. The entire rocket will then be assembled and a visual inspection will be performed, focused on finding any deformities or misalignments.

Avionics

Talon I is equipped with two flight computers, TeleMega V5, and RRC3, with their individual power supply and ejection charge wiring, to ensure absolute redundancy. Each flight computer will use a pull-pin switch to turn the computers on and off safely.

A 1s 3.7V 900MAH lipo battery will power the TeleMega and uses an external 2s 7.4V 900mAh lipo battery for the ejection charge system. The RRC3 will use a single 2s 7.4V 900mAh lipo battery as a power source for the flight computer and the ejection charge system.

Both flight computers will run 22 gauge silicone stranded wire to connect all the vital components. Each flight computer will run a wire connecting to terminal blocks attached to the bulkhead for the ejection charge system. These terminal blocks will connect ejection lighters, which can be easily swapped out after use.

Aerodynamics

All initial designs and simulations of the rocket are done in OpenRocket. This software allows us to quickly simulate different rocket designs, motors, and conditions, as it can output values such as velocity, acceleration, apogee (Figure 6), drag, and static margin, among others. Figure 6 shows OpenRocket’s estimated flight altitude plotted against time, giving us our apogee estimate. With these initial guesses from OpenRocket, we can settle on the design that we will manufacture.

Once the rocket is entirely manufactured, it will be tested in flight. Using our onboard avionics devices, flight data will be collected. Using this flight data, mainly the velocity data, we can estimate the rocket's coefficient of drag function. Taking this and any tweaks made to the rocket before the competition, we will estimate acceleration, velocity, and altitude numbers using our custom Simulink model, as shown below in Figure 7. This model takes thrust, mass, and coefficient of drag data and outputs the aforementioned quantities. Lastly, further analysis of the rocket, such as pressure, temperature, and velocity contours, as well as confirming drag at various flight conditions, are performed using the computational fluid dynamics (CFD) software ANSYS.

Payload

The payload system will be a functional 3U CubeSat structure in a vertically stacked configuration with total dimensions of approximately 4” x 4” x 12” and a weight of 8.8 lbs. The top 4” x 4” x 4” unit houses a GoPro HERO10 camera intended to record video of the flight through a viewport in the rocket fuselage. This camera will be mounted using a 3D-printed ABS mount and is intended to be activated using a smartphone app or voice activation. The middle unit houses an Extech VB300 3-axis G-force Data Logger intended to record vibration data throughout the flight.

This data will be collected from the data logger upon recovery of the Talon One and read using a computer via the USB. The collected vibration data will be compared with simulation data and hand calculations to generate a more accurate model and simulation for future use. The bottom unit houses additional inert weight required to meet the 8.8 lb requirement.

The payload system frame will be constructed using laser-cut MDF measuring 1⁄4” in thickness and housed inside a fiberglass coupler measuring 6” in diameter. It will be secured using a pair of stainless steel rods and plywood end caps. The system will be located above the main recovery compartment of Talon One.