Matches in SemOpenAlex for { <https://semopenalex.org/work/W42202059> ?p ?o ?g. }
Showing items 1 to 71 of
71
with 100 items per page.
- W42202059 abstract "Some hypersonic vehicles, such as those used in the HyShot supersonic combustion experiments conducted over the past decade, leave and re-enter the atmosphere while spinning. There is interest in whether it is possible to control the trajectory of such supersonic and hypersonic asymmetric spinning vehicles using control surfaces. The main aim of research presented in this thesis is to investigate whether it is possible to develop a guidance and control scheme for a spinning, aerodynamically asymmetrical vehicle. The HyShot Stability Demonstrator (HSD) was chosen to be the basis for modelling and simulation of such a scheme. The HSD is a 4.24 kg supersonic vehicle that uses four aerodynamic control surfaces arranged in a square configuration for manoeuvring. It was designed to represent the dynamics of a typical HyShot mission that has two scramjet engines arranged back-to-back on the fore body. The HSD is unique in that it has equal moments of inertia in pitch and yaw, which results in rotational dynamic equations that are equivalent to most missiles. However, the aerodynamic coefficients are not the same in pitch and yaw and this results in a unique control problem. Due to the combined asymmetry and aerodynamic control properties of the HSD, there are currently no existing guidance / control schemes in the open literature. The HSD is intended for future launch on a 5-inch Zuni sounding rocket. As a result, an important consideration for the guidance and control systems being developed is that they could be implemented in real-time in a flight computer. Attitude manoeuvres of an aerodynamically asymmetrical spinning vehicle are complicated primarily by the fact that the dynamics cannot be linearised in a mathematically well-posed fashion. The non-linear roll angle transformation results in plant dynamics that are insufficient for a linear attitude controller. One solution to the problem of asymmetrical spinning vehicle attitude control is presented in this thesis. A non-linear guidance law acts as an outer loop to issue commands to an autopilot system. The Angular Velocity Guidance law accepts sensor inputs and desired attitude information and calculates pitch and yaw-rate commands for autopilot input, based on error in attitude and additional compensation terms derived from Euler’s rotational equations. Aerodynamic properties of the HSD are calculated based on 2D shock-expansion theory with computational fluid dynamics corrections. The aerodynamic model is limited to Mach numbers above 1.8. The HSD has static stability derivatives Cm-alpha and Cn-beta of -2.37 and 5.37 at Mach 3.5 flow conditions. This results in different aerodynamic natural frequencies in each plane of the HSD. The non-linear and perturbation equations of motion are derived and discussed for two dynamic reference frames. The dynamics derived for the non-rotating body frame and the rotating body frame differ greatly and it is shown that for the HSD, the rotating body frame must be used to retain information in each plane of the HSD. Two body rate autopilot schemes were investigated for the attitude manoeuvres. The first scheme utilises two self-adaptive single-input, single-output (SISO) proportional plus integral controllers, derived using the pole placement technique. These controllers neglect cross-coupling due to spin-rate and are appropriate for use in the flight experiment as they are easily gain-scheduled for a range of Mach numbers and unknown spin-rate. The second scheme investigated is a multi-input, multi-output H-infinity controller that is shown to outperform the SISO controllers as long as the vehicle has a known, constant spin-rate. This controller was discounted for use in a flight experiment as it is more computationally intensive, is not easily tuned for spin-rate and has an H-infinity norm greater than 1 (hence does not meet the robustness criteria). A six degree-of-freedom numerical simulation was programmed in Computer Aided Design of Aerospace Concepts as a means of proving the guidance and control system. The simulation can be split into various modules such as kinematics, inertial navigation system, actuators, etc. The input/output characteristics of each module are discussed. It was found that due to the high aerodynamic natural frequencies of the small HSD payload, a simulation step time of 0.5 ms with the use of a predictor-corrector method of state-variable integration is necessary for a solution independent of integration time step. The simulations show that with the Angular Velocity Guidance developed in this thesis, the HSD would be capable of performing attitude manoeuvres at spin-rates of up to 3.5 Hz. The magnitude of manoeuvre possible is dependent on spin-rate. A 1 degree attitude change is possible in 0.7 s at a 3.5 Hz spin-rate, whereas at a spin-rate of 2.0 Hz the attitude change may be greater than 4.2 degrees in 0.5s. The device limitations that prevent manoeuvres at higher spin-rates for the HSD are the autopilot and actuator bandwidths and the inertial measurement unit. An overview of the hardware associated with a proposed future flight experiment is provided. Information on actuators, sensors, airframe and flight computer hardware and software allows future work to be carried out on the project." @default.
- W42202059 created "2016-06-24" @default.
- W42202059 creator A5022637065 @default.
- W42202059 date "2010-08-01" @default.
- W42202059 modified "2023-09-27" @default.
- W42202059 title "Attitude Guidance and Control for a Spinning, Asymmetrical Vehicle" @default.
- W42202059 hasPublicationYear "2010" @default.
- W42202059 type Work @default.
- W42202059 sameAs 42202059 @default.
- W42202059 citedByCount "0" @default.
- W42202059 crossrefType "journal-article" @default.
- W42202059 hasAuthorship W42202059A5022637065 @default.
- W42202059 hasConcept C121332964 @default.
- W42202059 hasConcept C122824865 @default.
- W42202059 hasConcept C127413603 @default.
- W42202059 hasConcept C1276947 @default.
- W42202059 hasConcept C13393347 @default.
- W42202059 hasConcept C13662910 @default.
- W42202059 hasConcept C146978453 @default.
- W42202059 hasConcept C154815118 @default.
- W42202059 hasConcept C154945302 @default.
- W42202059 hasConcept C198813307 @default.
- W42202059 hasConcept C205991772 @default.
- W42202059 hasConcept C2775924081 @default.
- W42202059 hasConcept C41008148 @default.
- W42202059 hasConcept C47446073 @default.
- W42202059 hasConcept C527307 @default.
- W42202059 hasConcept C78519656 @default.
- W42202059 hasConceptScore W42202059C121332964 @default.
- W42202059 hasConceptScore W42202059C122824865 @default.
- W42202059 hasConceptScore W42202059C127413603 @default.
- W42202059 hasConceptScore W42202059C1276947 @default.
- W42202059 hasConceptScore W42202059C13393347 @default.
- W42202059 hasConceptScore W42202059C13662910 @default.
- W42202059 hasConceptScore W42202059C146978453 @default.
- W42202059 hasConceptScore W42202059C154815118 @default.
- W42202059 hasConceptScore W42202059C154945302 @default.
- W42202059 hasConceptScore W42202059C198813307 @default.
- W42202059 hasConceptScore W42202059C205991772 @default.
- W42202059 hasConceptScore W42202059C2775924081 @default.
- W42202059 hasConceptScore W42202059C41008148 @default.
- W42202059 hasConceptScore W42202059C47446073 @default.
- W42202059 hasConceptScore W42202059C527307 @default.
- W42202059 hasConceptScore W42202059C78519656 @default.
- W42202059 hasLocation W422020591 @default.
- W42202059 hasOpenAccess W42202059 @default.
- W42202059 hasPrimaryLocation W422020591 @default.
- W42202059 hasRelatedWork W1531857674 @default.
- W42202059 hasRelatedWork W1532966001 @default.
- W42202059 hasRelatedWork W1965138445 @default.
- W42202059 hasRelatedWork W1974095650 @default.
- W42202059 hasRelatedWork W1992584073 @default.
- W42202059 hasRelatedWork W2019292891 @default.
- W42202059 hasRelatedWork W2049897789 @default.
- W42202059 hasRelatedWork W2076122309 @default.
- W42202059 hasRelatedWork W2079459144 @default.
- W42202059 hasRelatedWork W2107427882 @default.
- W42202059 hasRelatedWork W2222151871 @default.
- W42202059 hasRelatedWork W2223817653 @default.
- W42202059 hasRelatedWork W2415585002 @default.
- W42202059 hasRelatedWork W2575595682 @default.
- W42202059 hasRelatedWork W2744186747 @default.
- W42202059 hasRelatedWork W2755412619 @default.
- W42202059 hasRelatedWork W2898362964 @default.
- W42202059 hasRelatedWork W3021483641 @default.
- W42202059 hasRelatedWork W70391325 @default.
- W42202059 hasRelatedWork W3139763586 @default.
- W42202059 isParatext "false" @default.
- W42202059 isRetracted "false" @default.
- W42202059 magId "42202059" @default.
- W42202059 workType "article" @default.