“Fuel…feed on. Pressurization on. Pressure — ready. Cooling, flow — ready in both channels. Launches…let’s set for about eight seconds. Standby! Liftoff!”. After this command sounded on the test field, a historical event happened, which will become part of the chronicles not only for South Ural State University, but for Russia as well.
Breakthrough development
For the first time in the history of our country, a model of a multiengine propulsion system with a central body and guidance and navigation systems was successfully tested. This breakthrough development by SUSU scientists is a bright example of the power of scientific thought and proactive import substitution.
The idea of a reusable launch vehicle was proposed by the Academician V.P. Makeyev State Rocket Centre. In order to confirm the viability of this idea, a model of a propulsion system with a control system was required. So, this work was conducted at South Ural State University within the frameworks of the Ural Interregional Research and Education Centre for Advanced Industrial Technologies and Materials.
The President of our university, Doctor of Sciences (Engineering), Professor Aleksandr Shestakov was assigned by the SUSU Rector Alexander Wagner to head this work on the model’s creation. And it is not just because of the huge engineering experience of Professor Shestakov. He acted as the head and responsible officer of several successful projects related to space technologies.
While still a young engineer at the Academician V.P. Makeyev State Rocket Centre, for three years Aleksandr Shestakov had managed a big project on creating a dynamic stand for ground testing of control systems for a sea-launched ballistic missile. He developed a ground complex for testing the control system of the Soviet space shuttle Buran. In addition, he was engaged in the star-tacker calibration of the satellite, Earth and solar sensors. Three strategically important projects were fulfilled and technologies implemented. And now, under the guidance of Aleksandr Shestakov, another crucial project has been completed, in the fulfilment of which more than 40 scientists and specialists from SUSU were involved.
Preparations for the experiment took nine months. Young researchers were engaged in this work, and several dissertations for Candidate degree are being written in this field. In the course of successful testing, the propulsion system with sixteen jet engines lifted up to 10 metres, landed in the predetermined area and was ready for new launches.
Accurate parameters
The experiment was successful thanks to the combination of three main elements in the project: propulsion system, navigation system and control system. The multipurpose multiengine system is designed to be operated both on Earth and in outer space. Its specific feature is that the 16 low-thrust jet engines work for one common central body.
“The thrust for the flight of a space craft is created by the propulsion system. It has various sensors installed, as well as the systems of control and navigation. The flight is controlled based on data on the position, speed and accelerations,” shared Aleksey Shults, junior research fellow of the SUSU Laboratory for Research of the Physical and Chemical Properties and Gas Dynamics of Propulsion Systems for Reusable Launch Vehicles. “The experiment made it clear that the propulsion system does its work properly and sets the required level and direction of thrust. Besides that, the force of thrust changes in time within the set range. Therefore, the systems of control and navigation function properly as well.”
According to Associate Professor of the SUSU Department of Informational and Measuring Technology, Candidate of Sciences (Engineering) Dmitriy Katsai, for landing in the predetermined area, it is important to set a certain positioning of the engine block in space and feed the required information to the engine control system.
“As part of the experiment, we developed a strapdown combined inertial navigation system. It ensures the precision landing of a moving object in any weather conditions. Landing is the final and most important stage of flight, when the maximum number of troubles can occur. Thus the strict requirements to inertial navigation systems.
A complex of several information systems, independent of each other, allows to identify the position and orientation of a moving object in space. We use a strapdown inertial navigation system, computer vision system, and laser altimeter. The obtained information helps quite accurately determine the parameters of orientation of the multiengine propulsion system in space. The results that we saw during testing confirmed the reliability and precision of the operation of the combined navigation system.”
Important results
The model can move in space independently and calculate the trajectory of landing in the predetermined area. The task was solved thanks to the competences of the SUSU engineers and the cross-disciplinary approach.
“Our team was engaged in developing of the control system for the model,” explained Head of the Aircraft Control System Research Laboratory, Candidate of Sciences (Engineering) Viktor Sadov. “The specifics of this work is that we control a multichamber engine, which allows to regulate the thrust vector. That is why we can make the model move in any direction. In essence, our team integrated the work of other project groups. The experiment results show that the control system that we created ensures the movement of aircraft during the landing stage.”
The foreign community is aware of this unique development by the Chelyabinsk scientists. In one of his interviews, Elon Musk had to admit that they do not use rocket engines with a central body in the United States. According to the SpaceX founder, for now, this configuration has not been sufficiently tested yet, and many research studies still need to be conducted before a reliable prototype will be at the disposal of the world’s cosmonautics.
The experiment by the SUSU researchers opens up the prospects for operation of reusable launch vehicles. All the big projects by Roscosmos State Corporation start with models. The completed development and conducted experiment have shown the possibility of guided rocket movement at the landing stage.
“A world-level unique experiment has wrapped up the complicated work on creation of the model of a multiengine propulsion system,” commented the project head Aleksandr Shestakov. “The task was set as follows: to launch the model and make it land in a predetermined area. That is, we tested the system of the rocket model, which identifies its position using the navigation system, lands the rocket in a predetermined area and it is ready for the next launch. We have completed the set task one hundred percent.”
The SUSU scientists plan to adapt the obtained results to high-thrust engines. Fundamental research and scaling theory will help them do that. So, what is next?.. Next are the recovery rocket, Outer Space, and new breakthrough developments.