AAE 450 S08 MDRRev 1.0 – January 31, 2007
Purdue University AAE 450 - S08
Mission and SubsystemRequirements
Table of Contents
Table of Contents......
1.0 Change History......
2.0Scope......
3.0Mission Design Requirements......
4.0System Requirements – All Models......
4.1Aerothermodynamics......
4.2 Avionics......
4.5Dynamics & Control......
4.5Propulsion......
4.5Structures & Materials......
4.6 Trajectory Optimization......
A.Appendix......
1.1 Verification Method Definition......
1.1.1 Analysis1
1.1.2 Inspection1
1.1.3 Demonstration1
1.1.4 Test1
1.2 Verification Method Definitions for the Purposes of AAE-450......
1.2.1 Analysis......
1.2.2 Inspection......
1.2.3 Demonstration......
1.2.4 Test......
B. Appendix......
1.1 References:......
1.0 Change History
Date / Requirement No. / Description of Change1/31/07 / N/A / Initial Release – Rev 1.0
2.0Scope
The purpose of this document is to capture the technical requirements of this project for the mission and subsystems. It reflects the current design and should be used by the team as the source of model input, mass, power values, etc. It will be uploaded to the project website. The initial release is Rev 1.0 and subsequent revisions, prior to a major milestone, will be indicated by an increase in the value to the right of the decimal (i.e. Rev 1.1). After milestones, the value to the left of the decimal will be increased.
It is the responsibility of each subsystem to formulate the necessary requirements for that section for the various launch configurations. The PM, APM, and GCs will then review and agree upon this document before the initial release. Notice that to the right of each requirement, a verification method should be indicated. For the definition of each method and how they will apply to this project please see Appendix A.
Updates to the document will be made by the PM or APM. GCs should e-mail the PM and APM with any requirement changes.
3.0Mission Design Requirements
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
MDR-001 / The launch vehicle shall be able to deliver its payload size (200g, 1kg, and 5kg) into a 300 km perigee orbit. / X
MDR-002 / The launch vehicle shall be able to perform MDR-001 assuming no catastrophic failure with a success rate of 99.86% (3 sigma). / X
MDR-003 / The launch vehicle shall be able to perform MDR-001 including a catastrophic failure with a success rate of 90.00% (TBR). / X
4.0System Requirements – All Models
Key: Requirement NumberingGroup Abbrev. / Requirement No. / Launch Type (if none, applies to all types)
AERO / -XXX / Aircraft, Balloon, Ground, or none
4.1Aerothermodynamics
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
AERO-001 / The vehicle shall have a clearly defined CD, CM, and CL behavior vs. α over an altitude range for each stage. / X / X
AERO-002 / The vehicle shall have a clearly defined Cp for each stage. / X / X
AERO-003 / The vehicle shall have a clearly defined surface temperature versus α over an altitude range for each stage, accurate to within +/- 10% (TBR). / X / X
AERO-004 / The vehicle shall clearly defined aerodynamic loads vs. α over an altitude range for each stage, accurate to within +/- 10% (TBR). / X / X
AERO-005A / The vehicle first stage shall have a lifting body that can provide a moment of (TBD) for (TBD) seconds. / X / X
AERO-006 / Any inputs provided to other subsystems shall be accompanied by a 3 sigma uncertainty value. / X
4.2 Avionics
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
AVI-001 / The vehicle shall have a maximum power supply of (TBD) W, capable of distribution to all subsystems. / X / X
AVI-002 / The vehicle shall be able to command trajectory corrections autonomously. / X / X
AVI-003A / The mass of the avionics box shall be less than (TBD) kg. / X / X
AVI-003B / The mass of the avionics box shall be less than (TBD) kg. / X / X
AVI-003G / The mass of the avionics box shall be less than (TBD) kg. / X / X
AVI-004A / The volume of the avionics box shall be less than (TBD) m3. / X / X
AVI-004B / The volume of the avionics box shall be less than (TBD) m3. / X / X
AVI-004G / The volume of the avionics box shall be less than (TBD) m3. / X / X
AVI-005A / The avionics box shall reside on the (TBD) stage of the vehicle. / X / X / X
AVI-005B / The avionics box shall reside on the (TBD) stage of the vehicle. / X / X / X
AVI-005G / The avionics box shall reside on the (TBD) stage of the vehicle. / X / X / X
AVI-006 / The avionics shall provide the vehicle orientation, acceleration, position, and velocity to the flight controller. / X / X
AVI-007 / Any inputs provided to other subsystems shall be accompanied by a 3sigma uncertainty value. / X
AVI-008 / The vehicle shall have a primary communications system capable of (TBD) bits per second bandwidth transmission. / X / X
AVI-009 / The vehicle shall have a secondary communications system capable of (TBD) bits per second bandwidth transmission. / X / X
AVI-010 / The vehicle shall have a remote command and control communications system enabling secure command communication for the entire vehicle flight. / X / X
AVI-011 / All vehicle communications systems shall be able to communicate with the ground systems operation during the entire vehicle flight. / X / X
AVI-012 / A ground communications system shall be able to receive from the vehicle for the entire flight. / X / X
AVI-013 / A ground communications system shall be able to transmit secure commands to the vehicle for the entire flight. / X / X
AVI-014 / All communications systems shall be capable of constant communication and monitoring until a maximum orbit of (TDB) km has been achieved. / X / X
4.5Dynamics & Control
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
DC-001 / The vehicle shall be controlled autonomously to counteract the effects of weather veining. / X / X
DC-002 / The vehicle shall be able to achieve a maximum pitching moment of:
Payload (kg) / Moment (Nm)
.2 / (TBD)
1 / (TBD)
5 / (TBD)
/ X / X
DC-003 / The vehicle shall be able to achieve a maximum roll moment of:
Payload (kg) / Moment (Nm)
.2 / (TBD)
1 / (TBD)
5 / (TBD)
/ X / X
DC-004 / Any inputs provided to other subsystems shall be accompanied by a 3 sigma uncertainty value.
4.5Propulsion
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
PROP-001 / The propulsion group shall provide the following input parameters to the trajectory group for each stage:
Topt profile
Ae
Pe
mdot
tb
mo (initial mass) / X
PROP-002 / Any inputs provided to other subsystems shall be accompanied by a 3 sigma uncertainty value. / X
PROP-003 / The propulsion system shall provide thrust vectoring to a minimum of (TBD) degrees from the center axis. / X / X
PROP-004A / The vehicle shall have a minimum Isp of:
Isp (s)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / 200 TBR / 200 TBR / TBD
1 / 200 TBR / 200 TBR / TBD
5 / 200 TBR / 200 TBR / TBD
/ X / X
PROP-004B / The vehicle shall have a minimum Isp of:
Isp (s)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / 200 TBR / 200 TBR / TBD
1 / 200 TBR / 200 TBR / TBD
5 / 200 TBR / 200 TBR / TBD
/ X / X
PROP-004G / The vehicle shall have a minimum Isp of:
Isp (s)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / 200 TBR / 200 TBR / 200 TBR
1 / 200 TBR / 200 TBR / 200 TBR
5 / 200 TBR / 200 TBR / 200 TBR
/ X / X
PROP-005A / The vehicle shall achieve a minimum ΔV of (TBD) km/s. / X / X
PROP-005B / The vehicle shall achieve a minimum ΔV of (TBD) km/s. / X / X
PROP-005G / The vehicle shall achieve a minimum ΔV of (TBD) km/s. / X / X
PROP-006 / The vehicle shall have a minimum chamber pressure of 10MPa (TBR). / X / X
PROP-007 / The vehicle shall have a maximum inert mass fraction of 0.20 (TBR). / X / X
PROP-008A / The sea level thrust for any single engine shall be no more than (TBD). / X / X
PROP-008B / The sea level thrust for any single engine shall be no more than (TBD). / X / X
PROP-008G / The sea level thrust for any single engine shall be no more than 44 kN (TBR). / X / X
PROP-009 / The propulsion group shall provide the structures group with propellant mass (or density) for all stages of the launch vehicle. / X / X
PROP-010 / The propulsion group shall provide the structures group with engine mass for all stages of the launch vehicle. / X / X
PROP-011 / The propulsion group shall provide the structures group with optimal chamber pressure for each propellant. / X / X
PROP-012 / The propulsion group shall provide the maximum thrust for all stages. / X / X
PROP-013 / The propulsion group shall provide the structures group with nozzle diameter for all stages. / X / X
4.5Structures & Materials
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
SM-001A / The vehicle shall be able to withstand a maximum g loading of:
G Load
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-001B / The vehicle shall be able to withstand a maximum g loading of:
G Load
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-001G / The vehicle shall be able to withstand a maximum g loading of:
G Load
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-002A / The vehicle mass shall not exceed:
Mass (kg)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-002B / The vehicle mass shall not exceed:
Mass (kg)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-002G / The vehicle mass shall not exceed:
Mass (kg)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-003A / The vehicle shall be able to withstand a maximum structure temperature of:
Temperature (K)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-003B / The vehicle shall be able to withstand a maximum structure temperature of:
Temperature (K)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-003G / The vehicle shall be able to withstand a maximum structure temperature of:
Temperature (K)
Payload (kg) / Stage 1 / Stage 2 / Stage 3
.2 / (TBD) / (TBD) / (TBD)
1 / (TBD) / (TBD) / (TBD)
5 / (TBD) / (TBD) / (TBD)
/ X / X
SM-004 / The structures group shall provide trajectory with dimensions of each stage, including vehicle stage diameter, length, and nose cone dimensions. / X / X
SM-005 / The structures group shall provide minert for each stage. / X
SM-006 / The structures group shall provide a clear mode for CM and inertia tensor. / X / X
SM-007 / Any inputs provided to other subsystems shall be accompanied by a 3 sigma uncertainty value. / X
SM-008 / The launch vehicle shall achieve an overall reserve safety factor of 1.25 (NASA suggestion for unmanned launch vehicles). / X / X
SM-009 / The vehicle inert structural inert mass fraction shall not exceed:
Payload (kg) / Mass Fraction
.2 / 0.30 (TBR)
1 / 0.25 (TBR)
5 / 0.20 (TBR)
/ X
SM-010 / The strength tolerance limits of the launch vehicle materials shall coincide with B-basis values (95% tolerance bound on upper 10% of population). / X / X
4.6 Trajectory Optimization
Verification MethodReqt No. / Requirement / A / I / D / T / N/A
TRAJ-001 / The vehicle shall have a working trajectory simulation that models MDR-001. / X
TRAJ-002 / The vehicle trajectory simulation shall have a complete statistical analysis meeting MDR-002. / X
TRAJ-003 / The vehicle trajectory simulation shall output position, velocity, and acceleration vectors in body and inertial space for the entire time of flight (TOF). / X
TRAJ-004 / The vehicle trajectory simulation shall output all delta V losses for each stage, including losses due to gravity, drag, and steering. / X
TRAJ-005 / The vehicle trajectory simulation shall output final orbit parameters, including semi-major axis, eccentricity, and period. / X
TRAJ-006 / The vehicle trajectory simulation shall find and output optimal steering law parameters for each stage. / X
TRAJ-007 / The vehicle trajectory simulation shall output dynamic pressure variation with altitude. / X
A.Appendix
1.1 Verification Method Definition
1.1.1 Analysis1
The use of mathematical modeling and analytical techniques to predict the compliance of a design to its requirements based on calculated data or data derived from lower level component or subsystem testing. It is generally used when a physical prototype or product is not available or not cost effective. Analysis includes the use of both modeling and simulation.
1.1.2 Inspection1
The visual examination of the system, component, or subsystem. It is generally used to verify physical design features or specific manufacturer identification.
1.1.3 Demonstration1
The use of system, subsystem, or component operation to show that a requirement can be achieved by the system. It is generally used for a basic confirmation of performance capability and is differentiated from testing by the lack of detailed data gathering.
1.1.4 Test1
The use of system, subsystem, or component operation to obtain detailed data to verify performance or to provide sufficient information to verify performance through further analysis. Testing is the detailed quantifying method of verification…it is ultimately required in order to verify system design.
1.2 Verification Method Definitions for the Purposes of AAE-450
1.2.1 Analysis
Each group must come up with a computer model to show that the requirement can be met. If a model is not applicable, then historical data or research will serve as the analysis.
1.2.2 Inspection
For each production unit that requires inspection, a man hour count needs to be provided in order to estimate cost (TBR).
1.2.3 Demonstration
At this stage in design, it is not possible to have a reasonably detailed estimation for demonstration or the time associated with it.
1.2.4 Test
Any requirement that will be verified by test, prior to production, will have a test plan associated with it. It is the responsibility of the subsystem engineers to provide a test plan to the PM.
B. Appendix
1.1 References:
1. Department of Defense Systems Management College., “Systems Engineering Fundamentals,” Verification, Defense Acquisition University Press, Virginia, 2001, pp. 66. [
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