Next Article in Journal
The Unexplored Link between Communication and Trust in Aviation Maintenance Practice
Next Article in Special Issue
Review of Classical Diffusion-Limited Regression Rate Models in Hybrid Rockets
Previous Article in Journal
Supersonic Compressor Cascade Shape Optimization under Multiple Inlet Mach Operating Conditions
Previous Article in Special Issue
The Application of Computational Thermo-Fluid-Dynamics to the Simulation of Hybrid Rocket Internal Ballistics with Classical or Liquefying Fuels: A Review
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle

Theoretical Investigation on Feedback Control of Hybrid Rocket Engines

Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara City 252-5210, Kanagawa, Japan
Authors to whom correspondence should be addressed.
Aerospace 2019, 6(6), 65;
Received: 21 February 2019 / Revised: 8 May 2019 / Accepted: 10 May 2019 / Published: 3 June 2019


Despite the fact that hybrid propulsion offers significant benefits, it still suffers from some limitations such as the natural oxidizer to fuel ratio shift which induces variations of the engines’ performances while operating. To overcome that issue, Japan Aerospace Exploration Agency (JAXA) has been studying an innovative concept for several years based on the combination of controlled axial and radial oxidizer injections, called altering-intensity swirling-oxidizer-flow-type engine. This type of motor is theoretically capable of managing both the thrust and the oxidizer to fuel ratio independently and instantaneously by using a feedback control loop. To be effective, such engines would require in-flight instantaneous and precise thrust and an oxidizer to fuel ratio measurements as well as an adapted feedback control law. The purpose of this study is to investigate the effect of measurement errors on the engine control and to propose a regulation law suitable for these motors. Error propagation analysis and regulation law are developed from fundamental equations of hybrid motors and applied in a case where resistor-based sensors are used for fuel regression rate measurement. This study proves the theoretical feasibility of hybrid engines feedback control while providing some methods to design the engine and regression rate sensors depending on the mission requirements. View Full-Text
Keywords: hybrid rocket propulsion; swirl oxidizer injection; feedback loop control; error propagation analysis; resistor-based sensors hybrid rocket propulsion; swirl oxidizer injection; feedback loop control; error propagation analysis; resistor-based sensors

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Messineo, J.; Shimada, T. Theoretical Investigation on Feedback Control of Hybrid Rocket Engines. Aerospace 2019, 6, 65.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Aerospace EISSN 2226-4310 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top