SAWE Technical Papers

@inproceedings{3725,

title = {3725. HERMES: Hazard Examination and Reconnaissance Messenger for Extended Surveillance},

author = {Alexander Sandoval and Alexis Sotomayor and Brandon Santori and Brindan Adhikari and Colin Chen and Junzhe He and Katelyn Griego and Marcos Mejia and Michely Tenardi and Quinter Nyland},

url = {https://www.sawe.org/product/paper-3725},

year  = {2019},

date = {2019-05-01},

booktitle = {78th Annual Conference, Norfolk, VA},

pages = {11},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Norfolk, Virginia},

abstract = {The University of Colorado at Boulder Aerospace Engineering Senior Projects Team HERMES (Hazard Examination and Reconnaissance Messenger for Extended Surveillance) is currently designing, building, and testing a child scout rover (CSR). This is the fourth installment in the Jet Propulsion Laboratory's (JPL) Fire Tracker System. The Fire Tracker System is designed to operate in forest fire-prone areas for early fire identification. HERMES aims to improve the Fire Tracker System by navigating through a forest like environment to a location of interest (LOI) while determining a viable path for the Fire Tracker System's previous installment, a large less maneuverable mother rover. To do this, the CSR must traverse over obstacles up to 2.4 inches in height, vertical discontinuities (9 inches wide by 2.4 inches deep), over leaves, dirt, grass, and up or down 20 degree inclined slopes in both open and wooded area. Additionally, the CSR must drive forward and in reverse, as well as perform 360 degree turns in place. To complete these mission objectives, the CSR uses a sensor suite for obstacle and discontinuity detection, a two-motor configuration with a drivetrain and gearbox powering 6 wheels for traversing obstacles, and a moving linear mass stage that shifts the CSR's center of mass to enable traversing over discontinuities. While on a mission, the CSR will have the capability to detect any discontinuities using two downward angled, single beam LiDAR sensors. If a discontinuity is detected, the CSR will stop and notify the user at the ground station. The user at the ground station then commands the CSR into a semi-autonomous discontinuity traversal mode, where the CSR utilizes two ultrasonic sensors mounted on the bottom of the CSR to determine whether it is over a discontinuity or flat ground. These sensors signal the software to move the linear mass stage to shift the center of mass depending on the CSR's position over the discontinuity. The unique challenge of crossing discontinuities, and the solution, is discussed in this paper.},

keywords = {03. Center Of Gravity, 31. Weight Engineering - Surface Transportation, 33. Unmanned Vehicles},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{3621,

title = {3621. Development and Mass Tracking of the P-17 Prospector Launch Vehicle},

author = {Jose Vivas and Naoki Oishi and Dr. Eric Besnard},

url = {https://www.sawe.org/product/paper-3621},

year  = {2014},

date = {2014-05-01},

booktitle = {73rd Annual Conference, Long Beach California},

pages = {31},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Long Beach, California},

abstract = {The Prospector-17 (P-17) is a low cost suborbital launch vehicle designed to test wireless sensor technologies for aerospace control. Specifically, the goal of the project is to investigate the ability of distributed wireless sensors (accelerometers or strain gauges) for reconstructing elastic mode shapes onboard the vehicle and in real time in order to account vehicle dynamics in the flight control system. The vehicle design is derived from previous Prospector vehicles but modified to decrease the mass for higher performance. It is propelled by a 500 lbf thrust liquid oxygen (LOX) / ethanol rocket engine. The aluminum structure previously used was replaced with a composite structure composed of four carbon fiber/epoxy sections connecting the two stainless steel propellant tanks with some fiber glass/epoxy reinforcements. To further lessen the mass, some changes were done to the propulsion system, primarily moving the main valve actuation assembly (MVA) from inside the vehicle to the outside, thus becoming part of our ground support equipment (GSE). Also, since the MVA is usually placed towards the aft end of the vehicle, removing it shifts the center of mass forward, making the vehicle more stable. With all these changes the mass of the vehicle is predicted at 70 lbm, compared to 120 lbm for previous Prospector vehicles of the similar size. The predicted mass of the vehicle is derived from our mass tracking approach, which is done simultaneously with the vehicle design and manufacturing. An Equipment List and Mass Properties (EL & MP) datasheet is constantly updated to keep track of predicted total mass and center of mass using AIAA standards for mass tracking, allowing us to work on mass dependent aspects of the vehicle, such as fin design and the recovery system, before the vehicle is completely finished. The paper will introduce the wireless sensor network approach, present in detail the design of the P-17 vehicle and how our mass tracking practices of this and previous vehicles affected our design choices. P-17 is scheduled to be launched in early March 2014 in the Mojave Desert north of Edwards Air Force Base. The predicted performance will be compared with the actual flight test data.},

note = {California State University, Long Beach},

keywords = {33. Unmanned Vehicles},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{3515,

title = {3515. Wing Morphing Design Utilizing Macro Fiber Composite Smart Materials},

author = {LAUREN BUTT and ONUR BILGEN and STEVE DAY and CRAIG SOSSI and JOSEPH WEAVER and ARTUR WOLEK and DR. DANIEL INMAN and WILLIAM DR. MASON},

url = {https://www.sawe.org/product/paper-3515},

year  = {2010},

date = {2010-05-01},

booktitle = {69th Annual Conference, Virginia Beach, Virginia},

pages = {61},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Virginia Beach, Virginia},

abstract = {Demonstrate the abilities of morphing materials technology by modifying a current remote controlled aircraft model using an electric propulsion system and designing and fabricating control surfaces that use Smart Materials micro-fiber-composites (MFCs). The design must be marketable in the R/C community. 

The requirements for this project as described above contain basic guidelines for this Senior Design project. First and foremost, we must come up with a way to replace tradition servo controlled surfaces with MFC actuated surfaces in an effective manner. Not only will the control surfaces need to respond as well as, if not better than, the classic servo-motor system, but it will also need to be a fairly simple, potentially cost effective design that can easily be reproduced. The overall goal of this project is to showcase the capabilities of MFCs on an aircraft that could be reproduced on a large scale in today's R/C market.},

keywords = {33. Unmanned Vehicles},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{3422,

title = {3422. Weight Prediction of UAV Structures and Subsystems Using Parametric Design Methods},

author = {Mario Zimmerman},

url = {https://www.sawe.org/product/paper-3422},

year  = {2007},

date = {2007-05-01},

booktitle = {66th Annual Conference, Madrid, Spain},

pages = {25},

publisher = {Society of Allied Weight Engineers},

address = {Madrid, Spain},

organization = {Society of Allied Weight Engineers},

abstract = {For larger UAVs with more than 500 kg MTOM, technologies and assembly methods similar to man-carrying systems are used. These allow the use of known preliminary design methods according to Raymer, Roskam, or Stinton. In the case of smaller vehicles, the use of empiric equations made for man-carrying systems, most of the time, cause significant errors due to unscale-effects. Among other effects, this is based on a smaller decrease in size of connecting elements when decreasing overall part dimensions. Bonds of ribs with the outer skin can make up to 50% of the mass at small sizes. At reduced dimensions, breakouts for mass reduction cannot be made, which causes an unproportional mass increase of small parts. Since these problems appear in a similar way in nearly all parts of a UAV structure, a calculation using equations based on statistics for larger structures is no longer applicable. In order to accomplish a reasonable preliminary design of small UAV systems, the possibility of a preliminary design method by using a complete parameterization will be presented. Parameterization, in this case, means the computation and respective sizing of all system components with some key values and a number of model-changing parameters. Numerous structural elements as well as a large number of subsystems (e.g., starter and alternator-systems, reduction gear, retractable undercarriage, recovery system, etc.) were built as parametric models. The level of detail is set to a very high value, in fact down to the smallest shim, in order to take into account all unscale effects. These complex models were analyzed by a systematic variation of different parameters to get simplified mass-estimation equations which are now available for the mass prediction of small UAVs, including the effect of integrating different subsystems.},

keywords = {33. Unmanned Vehicles, 34. Advanced Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{3359,

title = {3359. Weight and Balance Considerations for Unmanned Combat Aerial Vehicles},

author = {California Polytechnic State University},

url = {https://www.sawe.org/product/paper-3359},

year  = {2005},

date = {2005-05-01},

booktitle = {64th Annual Conference, Annapolis, Maryland},

pages = {23},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Annapolis, Maryland},

abstract = {Sentinel Aerospace presents Cavalier, a ship-based morphing unmanned combat aerial vehicle (UCAV), in response to the 2004 ? 2005 American Institute of Aeronautics and Astronautics (AIAA) Graduate Team Aircraft Design Competition. Cavalier uses a combination of speed, stealth, and maneuverability to perform the suppression of enemy air defenses (SEAD) mission. The profile includes a 200 nautical mile cruise segment and a four hour loiter followed by a 0.757 Mach dash to the target area where four AGM-88 HARM missiles are to be expended, and a 5 g maneuver to egress the threat area. The alternate mission, which is also required, involves the same mission profile, but without engaging the enemy target. Cavalier effectively uses several forms of morphing on the wing. As the plane is to takeoff and land on LHA ships, a span limitation of 48 feet exists. Therefore, Cavalier uses shape memory alloy-actuated folding wingtips that extend after takeoff, and provide an additional 8.2 feet of span on each wing. Pivoting leading edge strakes are used to adjust planform area, mean sweep and thickness-to-chord for the different flight conditions. Hinge-less ailerons, based on the Smart Wing Program, will be employed to provide roll control while improving the radar cross-section. During the course of this investigation, it was realized that substantial savings could be achieved if morphing was applied to the propulsion system as well. The use of technology derived from the Smart Aircraft and Marine ProjectS demonstratiON (SAMPSON) was found to reduce the installation losses, in turn improving specific fuel consumption and net thrust. Additional morphing system concepts will be discussed that could yield a significant increase in performance. However, research and technology projects are still being conducted to determine a reasonable figure for benefits and penalties from these systems. As such, credit for these concepts has not been applied to the current configuration.},

keywords = {22. Weight Engineering - Structural Design, 33. Unmanned Vehicles, Student Papers},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{3345,

title = {3345. Weight Tracking for Controlled Growth of a Backpackable UAV},

author = {California Polytechnic State University},

url = {https://www.sawe.org/product/paper-3345},

year  = {2004},

date = {2004-05-01},

booktitle = {63rd Annual Conference, Newport, California},

pages = {95},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Newport, California},

abstract = {Vindication Aerospace proudly presents the Phoenix UAV system, a backpack portable UAV designed to provide day and night over-the-hill reconnaissance in response to the 2003/2004 AIAA Graduate Team Aircraft RFP. The Phoenix will work along side existing man portable UAV systems such as Dragon Eye and Desert Hawk, but it will have greater capability. The Phoenix can operate in 30 knot winds and be launched out of a 20 meter clearing with 10 meter obstacles on all sides. The Phoenix can provide troops with at least one hour on station up to 20 kilometers away. It also packs up into package 0.18 ft3 larger than its competitor, Dragon Eye. This paper is a design report which highlights some of the unconventional ways in which preliminary sizing, weight estimation, and performance analysis can be applied to arrive at a workable solution. The Phoenix is not born out of textbook equations, it is derived from system sizing, derived equations, and real world testing. Because weight is such an integral component of aircraft design, the entire report was deemed relevant to the study of weight tracking and how it influences an evolving design.},

keywords = {22. Weight Engineering - Structural Design, 33. Unmanned Vehicles, Student Papers},

pubstate = {published},

tppubtype = {inproceedings}

}