Tiger III
Tiger III - Rendering XRay
The Goal
After successfully launching Tiger II with passive stabilization, it was time to tackle the goal of achieving an actively stabilized flight. Tiger III is the first rocket prototype designed to help achieve this goal.
CAD
Tiger III incorporates a thrust vector control (TVC) system to enable actively stabilized flight. As the main body, it uses a wastewater tube.
Thrust Vector Control
To achieve active stabilization, Tiger III incorporates a thrust vector control system. At the time, BPS.space was the only other YouTube channel working on achieving active stabilized flight, and his design inspired my initial TVC system.
In essence, the rocket engines are independently gimballed along the pitch and yaw axes. One servo, mounted on the rocket frame, controls one TVC axis, while another servo, mounted on the first part of the gimbal, controls the second axis. Both servos are of the 9g type and are linked to the engine mount by a metal rod.
Tiger III - TVC
Parachute Deployment
In addition to the TVC system, Tiger III is the first rocket where a recovery system was crucial. With the inclusion of electronics and fragile hardware, ensuring the rocket's safe return was paramount.
My first parachute design involved two rubber bands. The rubber band is tensioned between the nose cone and the parachute hull, creating a force that wants to rotate the nose cone open. Another rubber band on the opposite side prevents this from happening. To deploy the parachute, a heating wire dissects the restraining rubber band, allowing the nose cone to open and the parachute to deploy.
The parachute is situated inside the parachute hull. Getting this design right required several revisions. Below are three of them. The final version used a split plate, which made it possible to use three very small chutes instead of one.
Parachute Deployment System - V1
Parachute Deployment System - V2
Parachute Deployment System - V3
Avionics
For an actively stabilized flight to work, this rocket required its first avionics system.
I used an Arduino Uno R3 as the microcontroller and an MPU6050 to assess the rocket's orientation.
Although a pyro channel was necessary to dissect the rubber band for the parachute deployment system, it was not implemented in this avionics setup.
Testing
The first TVC system worked reasonably well in combination with the mockup avionics system. In the video below, you can see the engine mount moving as the orientation of the MPU6050 changes.
Tiger III was never launched, as the avionics system proved insufficient, and both the TVC and parachute deployment systems required further revision.
Instead of refining Tiger III, I decided to move on to Tiger IV to incorporate all the lessons learned and improve upon the design.
Project by Johannes Moser
