Next Generation Carbon Fiber Airframe

Product Design Specifications Report – Winter 2016

Group Members

David Edwards

Alex Kollen

Danny Johnson

Alex Chan

Nicholas Cho

Academic Advisor

Dr. Jun Jiao

Table of Contents

Introduction……....………….………………………………………………………………….....2

Purpose of PDS Documentation…………………………………………………………………..3

Mission Statement………………...……………………………………………………………....3

Project Plan……….………………...……………………………………………………………..4

Customer Identification………………...…………………………………………………………4

Customer Feedbacks and Interviews…....……....…………………………………………..…….5

Product Design Specifications……...……………….…………………………………………….5

Conclusion……………………………....……………………………………………………...…6

Appendix………………...………………………………………………………………………..7

Introduction

The Portland State Aerospace Society (PSAS) has a goal of being the first university to break the Karman Line (100 km) with a high powered rocket. To achieve this milestone, the weight, thrust, lift, and drag of the rocket must be optimized. These forces present on a rocket in flight are shown in Figure 1.

Figure 1: Schematic of four forces on a rocket.

Since the rocket is usually launched in the vertical direction, both weight and drag will act in direct opposition to the thrust. This will increase the rate of fuel expended and limit the total height that the rocket can travel. Out of the four forces, this project will address weight and drag. Specifically, the next generation rocket will increase the carbon fiber airframe diameter and reduce the weight of the rocket while maintaining the same amount of thrust to propel the rocket. Furthermore, the surface finish will be improved from the previous rocket to reduce the drag force. The purpose of this project is improve the design of the previous rocket.

Purpose of PDS Documentation

The Product Design Specification document describes the design criteria for the carbon fiber airframe in terms of priority, customers, metrics, target, basis, and verification. Further details are shown in the tables in the PDS section. This document will serve as a guide to ensure that all of the important requirements for the project are met.

Mission Statement

The previous team had delivered an 8 inch carbon fiber rocket with 80% weight reduction compared to PSAS’s previous aluminum rocket, but there were several problems. First of all, the surface finish was too rough for efficient travel at mach 3 speed, and secondly, the manufacturing process was too complicated to replicate without some training.

The purpose of the project is to maintain the goal of a weight reduction of the rocket airframe by 80% (with respect to the weight of a 14 inch diameter aluminum rocket) , improve the surface finish of the rocket, and to simplify the manufacturing process.

By June 2016, two improved 14 inch carbon fiber airframe modules will be delivered to PSAS, one to be used for display or future use and one to be subjected to simulations and destructive testing. Well organized documentation will also be presented which will include data and other information on all design aspects for both the new carbon fiber module design and the manufacturing process.

Project Plan

The project timeline and major milestones are outlined in table 1 below. For further details, see appendix A for the Gantt Chart. This chart shows the tentative schedule for each of the major design methodology steps and all the substeps required to complete the project.

Project Plan
Tasks / Date of Completion
External Search / 13-Feb
Internal Search / 13-Feb
Concept Design / 20-Feb
Concept Selection / Ongoing
Material Selection/Purchasing / 29-Feb
FEA modeling / 29-Feb
Mold and Coupler Ring Fabrication / 21-March
First Prototype / 4-April
Final Product / 21-May
Testing and Documentation / 30-May
Final Presentation and Project Close-out / 4- June

Table 1: Major Milestones

Customer Identification

There are no external customers, but the internal customers are PSAS, the capstone course, and the PSU faculty advisor.

Customer feedbacks and interviews

Our customer (PSAS) has been encouraging and pleased with our process so far. Some of their concerns we have addressed so far this term include; the scope in which we are allowed to change/improve the current manufacturing process, the material selection, reaching out to previous sponsors for material donation in addition to make new connections with carbon fiber companies in the Northwest region.

PDS

In the tables below, the relevant Product Design Specifications are categorized by High Priority, Medium Priority, and Low Priority.

HIGH PRIORITY
Criteria / Requirement / Customer / Metrics / Target / Basis / Verification
Performance / Withstand Mach3 Forces / PSAS / Safety Factor / 2 / Group Decision / Design Analysis and Testing
Smooth Surface / PSAS / ?m / <0.1 / Group Decision / Prototype
Size / Diameter / PSAS / Diameter in inches / 14 / PSAS / Prototype
Weight / Less Than Previous Model / PSAS / % of Weight from Previous Model / 50< / PSAS / Prototype
Installation / Ease of Assembly / PSAS / Low Skill / PSAS / Prototype
Documentation / Simulations / PSAS / Documented / 0 Missing Documents / PSAS / Report
New Module Design / PSAS / Documented / 0 Missing Documents / PSAS / Report
Manufacturing Process / PSAS / Documented / 0 Missing Documents / PSAS / Report
Testing / Perform All Necessary Tests / Project
Team / Max Stress, Shear Stress, Temperature Profile, Heat Flux / 100% verified / Group Decision / Testing

Table 2: High Priority product design specifications

MEDIUM PRIORITY
Criteria / Requirement / Customer / Metrics / Target / Target basis / Verification
Quantity / At least 2 / PSAS / Number / 2 / PSAS / Prototype
Material / Reasonable Prices / Self / $ / Inexpensive / Budget / Design
Aluminum Rings / PSAS / yes/no / yes / PSAS / Design
Timeline / PDS / PSU / Deadline / 1 Report / PSU / Report
Progress Report / PSU / Deadline / 1 Report / PSU / Report
Final Report / PSU/PSAS / Deadline / 1 Report / PSU/PSAS / Report
Gantt Chart / Self / Deadline / 1 Table / Self / Report

Table 3: Medium Priority product design specifications

LOW PRIORITY
Criteria / Requirement / Customer / Metrics / Target / Target basis / Verification
Environment / Not Environmentally Hazardous / Self / Contamination of Surrounding / No Detectable Contaminants / Group Interest / Design

Table 4: Low Priority product design specifications

Conclusion

The PDS document highlights the important criterias that will guide the Next Generation Carbon Fiber Airframe project. For this project, it is important to simplify and document the manufacturing process so that the efforts put into this project can be used to pioneer future iterations. With each improvement, PSAS may someday build a rocket capable of reaching the Karman Line.

Appendix

Appendix A-Gantt Chart

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