Articulated Vehicles With Active Suspension Mechanism For Mobility On Uneven Terrain, 2015 Tianjin University of Technology
Articulated Vehicles With Active Suspension Mechanism For Mobility On Uneven Terrain, Fang Feng, Chen Yan
To improve the mobility of wheeled robots traversing on a fully 3D uneven terrain while maintaining a stable posture is the primary focus in this paper. The mobile robots with articulated mechanism in their suspension system can offer many advantages over classic mobile robots, such as reconfigurability of wheel-axle with respect to the chassis. Thus, locomotion systems with multiple leg-wheels now permit enormous reconfigurability of the chassis frame with respect to the ground frame. In this paper, first we focus on exploiting a systematic way to enhance contact kinematics i.e., reducing the slippage and improving traction forces at wheel-ground ...
Optimal Design Of Stair-Climbing Mobile Robot Through Kinetostatic Optimization, 2015 Tianjin University
Optimal Design Of Stair-Climbing Mobile Robot Through Kinetostatic Optimization, Chen Yan, Fang Feng
Navigation on the rough terrain is a complex task which requires the robot to be considered as a holistic system. Considering the physical dimensions and capabilities of mobile robot to do maneuvering on uneven terrains is the main focus of this paper. Obstacle surmounting capability is highly desirable feature for rough-terrain locomotion systems. Here, we examine the kinematic and static optimization of articulated subsystem designs by offering an reconfigurable leg-wheel subsystem for increasing locomotion capabilities. In this paper, we try to achieve the greatest motion-ranges between wheel axle and chassis while reducing the overall actuation requirements by torsion spring assist ...
The Creation Of A Communication Systems For A Small Satellite At The University Of North Dakota, Michael Hlas, Jeremy Straub, Ronald Marsh
Software defined radios (SDRs) are poised to significantly enhance the future of small spacecraft communications. They allow signal processing to be performed on a computer by software rather than requiring dedicated hardware. The SDR takes data from the flight computer and converts it into an analog signal that is transmitted via the spacecraft antenna. Because the signal processing is done in software, the radio can be easily reconfigured.
Data is prepared for transmission by TCP stack software onboard the OpenOrbiter Spacecraft and placed in a queue while the spacecraft is listening for a signal from a ground station. When a ...
Update On The Development Of A 1-U Cubesat At The University Of North Dakota, 2015 SelectedWorks
Update On The Development Of A 1-U Cubesat At The University Of North Dakota, Jeremy Straub, Ronald Marsh
An overview of the progress on the development of the OpenOrbiter CubeSat is presented. This covers, at a high level, the work that has been performed during the past year and foundational work that occurred prior to this. This poster also discusses future plans for the Open Prototype for Educational NanoSats (OPEN) framework and the OpenOrbiter Small Spacecraft Development Initiative. Particular focus is given to the ongoing work to prepare for an orbital launch, which the program has been down-selected for through the NASA ELaNa CubeSat Launch Initiative program.
In addition to this discussion of the program’s origins, goals ...
A Low-Cost Radio For An Open Cubesat, 2015 SelectedWorks
A Low-Cost Radio For An Open Cubesat, Michael Wegerson, Jeremy Straub, Ronald Marsh
The OpenOrbiter small spacecraft development program aims to develop a template that can be used by colleges and universities world-wide to ‘jumpstart’ their own CubeSat development program. It is doing this through the development of designs (and implementations to test the designs functionality) of all basic CubeSat subsystems. A CubeSat can prospectively perform elements of a mission that would otherwise have required the development and deployment of a multi-million dollar satellite, thus, interest in CubeSats in industry and government is strong as well. The Open Prototype for Educational Nanosats (OPEN) design being produced by the OpenOrbiter program may, thus, be ...
Open Prototype For Educational Nanosats Cubesat Structural Design, 2015 SelectedWorks
Open Prototype For Educational Nanosats Cubesat Structural Design, Benjamin Kading, Jeremy Straub, Ronald Marsh
CubeSats are a class of small satellites that have recently gained significant interest and are being developed and used for engineering test missions, bona fide research and various other applications. A 1-U CubeSat (the original form factor) has nominal dimensions of 10 cm x 10 cm x 10 cm and a mass of no more than 1.33 kg (however, some integrators are now consistently allowing higher mass levels). Due to their small size and the demonstrated ability to successfully use consumer-grade electronics in low-Earth orbit, CubeSats cost significantly less than larger sized satellites. These reduced costs, however, are still ...
Mechanical Design Of A Low-Cost Deployable Solar Panel Array For A 1-U Cubesat, 2015 SelectedWorks
Mechanical Design Of A Low-Cost Deployable Solar Panel Array For A 1-U Cubesat, Thomas Mcguire, Skye Leake, Michael Parsons, Michael Hirsch, Benjamin Kading, Jeremy Straub, David Whalen
CubeSats are small spacecraft with a nominal size of 10 cm x 10 cm x 10 cm and a mass of 1.33 kg (though some launch providers are now supporting expanded mass levels). While the CubeSat form factor has reduced the time and cost of spacecraft development, the required resources are still beyond the grasp of many colleges and universities. The Open Prototype for Educational Nanosats (OPEN) concept aims to solve this problem. OPEN is an inexpensive modular CubeSat that can be produced with a parts budget of less than $5,000. The OpenOrbiter program is working to develop ...
Design And Development Of A Payload Area Sub-Structure For A 1-U Cubesat, 2015 SelectedWorks
Design And Development Of A Payload Area Sub-Structure For A 1-U Cubesat, Tristan Plante, Jordan Forbord, Alexander Holland, Landon Klein, Benjamin Kading, Jeremy Straub, Ronald Marsh
Advancements in the miniaturization of electronics and other factors have allowed CubeSats, small satellites that can be created at a much lower cost than a large satellite, to perform numerous useful tasks. CubeSats, which are nominally 10 cm x 10 cm x 10 cm with a mass of less than 1.33 kg, are also developed in academic institutions to aid student learning; however, the development and launch of CubeSats can be expensive. Because of this, the Open Prototype for Educational NanoSats (OPEN) aims to make CubeSat development more affordable by developing a set of design documents as well as ...
Scheduling Algorithm Development For An Open Source Software Spacecraft, 2015 SelectedWorks
Scheduling Algorithm Development For An Open Source Software Spacecraft, Calvin Bina, Jeremy Straub, Ronald Marsh
The OpenOrbiter project at the University of North Dakota is working to develop a set of designs for a CubeSat class spacecraft as well as a working, modular collection of open source code that can be used by other CubeSat projects as a starting point for development. The availability of these designs and this codebase should foster accelerated development for other CubeSat projects, allowing those projects to focus their effort on their own application area, instead of reinventing the proverbial wheel. One aspect of this is to implement a task scheduler which will run on a Raspberry Pi flight computer ...
Design Of An Onboard Distributed Multiprocessing System For A Cubesat, 2015 SelectedWorks
Design Of An Onboard Distributed Multiprocessing System For A Cubesat, Michael Wegerson, Jeremy Straub, Ronald Marsh
The OpenOrbiter program aims to develop a low-cost framework to facilitate the development of CubeSat-class spacecraft (small spacecraft with nominal dimensions of 10 cm x 10 cm x 10 cm) for a parts cost of less than $5,000. To validate the framework that has been developed, a prototype unit will also be fabricated and tested in low-Earth orbit. In addition to validating the development of Open Prototype for Educational Nanosats (OPEN) framework, the spacecraft will perform on-orbit science. One aspect of the science mission will be to demonstrate and characterize the efficacy of two types of image processing. To ...
Hardware Design For An Intelligent Attitude Determination And Control System (Adcs), Michael Wegerson, Matt Partridge, Nathan Crocker, David Schindele, Broc Friend, Levi Lewis, Ben Johnson, Jeremy Straub, Ronald Marsh
Attitude determination and control is one of the most important subsystems on any satellite, allowing the spacecraft to sense and control its orientation while in orbit. Attitude sensing is achieved by measuring the satellite’s acceleration, rotation, and it’s alinement to Earth’s magnetic field. With its orientation determined, a satellite can use one or several different techniques to regulate its motion. One methods is to use of a pseudo-passive system of electromagnets (called magnetorquers) powered at specific times to use magnetic fields generated by the Earth to exert force on the spacecraft, thereby controlling the rotation of the ...
Electrical Power System For An Open Hardware Cubesat, 2015 SelectedWorks
Electrical Power System For An Open Hardware Cubesat, Sofiane Chaieb, Michael Wegerson, Jeremy Straub, Ronald Marsh, David Whalen
The OpenOrbiter program is developing a complete set of CubeSat hardware and software to facilitate the development of a 1-U CubeSat (10 cm x 10 cm x 10 cm, 1.33 kg spacecraft) with a parts cost of less than $5,000. This poster covers the electrical power system (EPS) for that spacecraft. The EPS is an assemblage of components that supplies all spacecraft subsystems with power, while performing health assessment of the battery and electrical buses. The EPS has a crucial role in the spacecraft and thus has to be developed and tested with extreme care.
The EPS generates ...
Efficient General Computational Method For Estimation Of Standard Atmosphere Parameters, 2015 AAR Aerospace Consulting, LLC
Efficient General Computational Method For Estimation Of Standard Atmosphere Parameters, Nihad E. Daidzic Ph.D., Sc.D.
International Journal of Aviation, Aeronautics, and Aerospace
Knowledge of standard air temperature, pressure, density, speed of sound, and viscosity as a function of altitude is essential information in aircraft design, performance testing, pressure altimeter calibration, and several other aeronautical engineering and aviation science applications. A new efficient computational method for rapid calculations of standard atmospheric parameters up to 86 orthometric km is presented. Additionally, mass and weight of each standard atmospheric layer were calculated using a numerical integration method. The sum of all fractional masses and weights represents the total mass and weight of Earth’s atmosphere. The results obtained here agree well with measurements and models ...
Comparison Of Aircraft Tire Wear With Initial Wheel Rotational Speed, 2015 University of Sussex
Comparison Of Aircraft Tire Wear With Initial Wheel Rotational Speed, Abdurrhman A. Alroqi, Weiji Wang
International Journal of Aviation, Aeronautics, and Aerospace
The impact an aircraft has on its tires when it lands has been problematic practically since the invention of the airplane. Upon touchdown, the tires frequently smoke as rubber burns off and tire material is worn away while the tires slip up to a steady rolling speed. To minimise tire slip, torque or spin mechanisms could be added to each tire assembly to accelerate the tire to match the landing speed. Patents have been registered since the 1940s to improve tire safety and performance, decrease the substantial wear that results from every landing, and save airline companies the cost of ...
An Overview Of The Openorbiter Autonomous Operating Software, 2015 SelectedWorks
An Overview Of The Openorbiter Autonomous Operating Software, Dayln Limesand, Timothy Whitney, Jeremy Straub, Ronald Marsh
The OpenOrbiter spacecraft aims to demonstrate the efficacy of the Open Prototype for Educational Nanosats (OPEN) framework. Software is an important part of this framework. This paper discusses the operating software for the spacecraft (which runs on top of the Linux operating system to command spacecraft operations). It presents an overview of this software and then pays particular attention to the aspects of software design that enable onboard autonomy. It also discusses the messaging scheme that is used onboard and the testing and validation plan. Finally, it discusses system extensibility, before concluding.
Analysis Of A ‘Turn-Key’ No Hardware Space Mission Using The Orbital Services Model, Jeremy Straub
Many applications that would benefit from access to space cannot afford the cost of spacecraft development, launch and operations. Other operations require only a fraction of a spacecraft or complete use of a spacecraft for a limited period of time. This paper considers the value of a ‘turn-key’ style space mission. It considers what types of missions could be reasonably conducted using this approach. The economics of being a service provider are considered. Then, a prospective mission concept for one OSM ‘turn-key’ mission is presented. The value proposition of this mission is assessed and the hardware and other capabilities required ...
Nanosatellite Scheduling Using A Dictionary Module And A ‘Useful Trick’ With Coded Unsigned Integers, Monilito Castro, Jeremy Straub
Schedulers for small spacecraft must satisfy the dual requirement of generating very efficient schedules while concurrently minimizing the resources required to create the schedule. This paper proposes a technique for searching for tasks that can be utilized to fill particular schedule locations. This approach is based on a modular system for storing important variables. This modular system has three important variables: t0, x0 and y0. The variable y is latitude and x is longitude. Time variable t is an integer and each unit represents a time quantum. They are related to each other by three functions Ft, Fx, and Fy ...
Swarm Intelligence, A Blackboard Architecture And Local Decision Making For Spacecraft Command, Jeremy Straub
Control of a multi-spacecraft constellation is a topic of significant inquiry, at present. This paper presents and evaluates a command architecture for a multi-spacecraft mission. It combines swarm techniques with a decentralized / local decision making architecture (which uses a set of shared blackboards for coordination) and demonstrates the efficacy of this approach. Under this approach, the Blackboard software architecture is used to facilitate data sharing between craft as part of a resilient hierarchy and the swarm techniques are used to coordinate activity. The paper begins with an overview of prior work on the precursor command technologies and then presents five ...
Using A Constellation Of Cubesats For In-Space Optical 3d Scanning, 2015 SelectedWorks
Using A Constellation Of Cubesats For In-Space Optical 3d Scanning, Jeremy Straub
The assessment of in-space objects is an area of ongoing research. Characterization of resident space objects (RSOs) can be useful for assessing the operating status of operator-affiliated or non-affiliated space assets, identifying unknown objects or gathering additional details for known objects. Under the proposed approach, a ring-like constellation of CubeSats passes around the target (at a distance) collecting imagery. This imagery is then utilized to create a 3D model of the target. This paper considers several key elements of a constellation to perform this type of imaging, including the constellation design and imaging capabilities required and the astrodynamics relevant to ...
Small Satellite Communications Security And Student Learning In The Development Of Ground Station Software, Scott Kerlin, Jeremy Straub, Jacob Huhn, Alexander Lewis
Communications security is gaining importance as small spacecraft include actuator capabilities (i.e., propulsion), payloads which could be misappropriated (i.e., high resolution cameras), and research missions with high value/cost. However, security is limited by capability, interoperability and regulation. Additionally, as the small satellite community becomes more mainstream and diverse, the lack of cheap, limited-to-no configuration, pluggable security modules for small satellites also presents a limit for user adoption of security.
This paper discusses a prospective approach for incorporating robust security into a student-developed ground station created at the University of North Dakota as part of a Computer Science ...