Research Blog 4: Unmanned Systems Space-Based Applications

 The hot ticket item for this weeks research blog is wither it is more beneficial for a manned system to explore the depths of space or are unmanned systems more adapt to the challenges of space exploration? For this review I am taking a look at two different articles, both hit certain points of the positive and the negative of the use of manned and unmanned systems while exploring space. Neither of these articles will take a certain side of which one is better or should be used above the other and that is the stance that I will explain that I hold on this debate.

The first article comes from the University of Central Florida's magazine PEGASUS. Within it two stances are made for manned systems and against manned systems. Joshua Colwell Ph.D gives a more humanistic approach to why manned systems should be given presidency over unmanned systems. He states "The manned exploration of space is an expression of one of our finest aspects — curiosity. To truly satisfy that curiosity we need to be participants...While valuable advances have been made because of the manned program, it cannot and should not be justified on the grounds of scientific advancement. It is instead about something equally important as science — the inspiration of our species to pursue lofty goals." (Colwell & Britt, 2014) Dr. Colwell's stance on this is important to note that we as humans need to have that participation in the continuing exploration of space. That "hands on approach" that sparks our imagination and furthers our drive to continue and invent. Dr. Colwells colleague Daniel Britt argues for the use of unmanned systems while exploring space. "For crewed spacecraft, Venus and Mercury are impossibly hot, and the asteroid belt and Jupiter are impossibly cold. The longer travel times to these worlds would be a death sentence from radiation exposure, not to mention bone loss and muscle atrophy." (Colwell & Britt, 2014). Dr. Britt's argument to use unmanned systems to explore space is not entirely to say that humans should no longer be apart of the exploration of space, but at the time being and technology being as it is for the time and needs that manned systems would need to explore the vastness of space. Unmanned systems are a precursor to help pave the way for safe passage by manned systems to advance in technology that would help to lessen the time for travel and to advance protection against debris and radiation that would be harmful to human travelers. Both writers in this article agree that at the moment unmanned systems are the most cost effective for space exploration, yet both do believe that manned and unmanned systems should work together in exploration. "that each endeavor ultimately strengthens the other." (Colwell & Britt, 2014).

The second article comes from Mary Wood at the Prezi website creating a compare and contrast of the costs and benefits between manned and unmanned spaceflight. Throughout her presentation the author describes the different strengths and weaknesses of manned and unmanned spaceflight in the following categories: cost, safety, and "WOW" factor. Her first category identifies the costs between manned and unmanned with unmanned coming out the winner of the two as it relates to costs. Her example looks at the Space Shuttle Endevour which was estimated to cost $206 billion. Compared to the unmanned systems such as the Messenger, Gailieo, New Horizons, and the Hubble have altogether come out to around $10.56 billion to build and maintain. This category is easy to see how unmanned is the more efficient outcome for cost analysis. The next category of safety can be correlated back to the first article where manned systems have a higher risk involved, not only with the radiation and loss of bone and muscle mass on the human but also from the initial launch of the spacecraft. "14 lives have been lost during the shuttle program, and 18 lives in total have been lost in Space. Two shuttles (Challenger, Columbia) have undergone disasters and were not fully recovered." (Wood 2016). The loss of an unmanned system though expensive, it can not begin to compare to the loss of human life. The winner for this category of safety is unmanned systems, since a robot can always be rebuilt. The final category is the "WOW" factor that Wood mentions. The wow factor is the humanistic side of space exploration. Unmanned systems can indeed give us a clear view and picture of what space looks like. Without that hands on experience it means little to nothing in the great scheme of our minds and imagination.

 In the end what is the stance that I take on unmanned systems over manned systems? The factors weighing against manned systems seem to be substantial than unmanned systems, making unmanned systems seem as though the likely candidate to continue pressing with and leaving manned system exploration as a subtle dream of space travelers long past. This though is not the case. I see both these systems as working together to further our reaches out into the vastness of space. Unmanned systems will help to pave the way for manned systems. Unmanned systems would be able to safely transport supplies and help set up environments on other worlds to help manned systems to reach these worlds and be sufficient when humans colonize other worlds. Though still a few years out the synergy needed to reach Mars or other worlds between manned and unmanned systems is needed and still highly advisable to pursue.


References: 

Colwell, J., & Britt, D. (2014). Are robots or astronauts the future of space exploration? PEGASUS. Retrieved from http://www.ucf.edu/pegasus/opinion/ 

Wood, M. (2016, July 11). The costs and benefits of manned and unmanned Spaceflight. Retrieved November 20, 2016, from Prezi, https://prezi.com/u7ncq8jz4s8e/the-costs-and-benefits-of-manned-and-unmanned-spaceflight/ 

Research Blog 3: Unmanned Aerospace Systems

Further endurance of UAVs for longer flight time.

Unmanned aerial vehicles (UAVs) have come a long way from the civilian use of "drones" for personal entertainment such as hobby drone flyers, movie entertainment filming, and topography mapping, to the military use of surveillance and target neutralization. The benefits of UAVs include the lack of a crew, the ability to operate in hazardous conditions, the cost saving from these previous benefits and the increased endurance of drones are all major benefits. Endurance is one of the most sought after attribute when purchasing or using any UAV. Endurance time for most .personal UAVs for the high end models can range any where from 20 minutes (TRAXXAS 7908 ATON) to 26 minutes (DJI Phantom 4). (Jonathan, 2016) For military UAVs the endurance of these vehicles far overcome their civilian counterpart. The maximum endurance for the RQ-4 Global Hawk is around 35 hours, as where the MQ-1 and the MQ-9 Predator drones endurance is a max of 40 hours of continuous flight time. (“AeroWeb | MQ-1/MQ-9 predator/reaper,” 2016)

As the use of UAVs becomes more persistent, so does the outlook to different methods to continuing longer flight time for these vehicles and the ability to recharge or refuel them without the need of human intervention. One such attempt is by outfitting a UAV with solar panel "Solar panels installed on the external surfaces of the aerial vehicle collect the power from the sun during daylight and transfer it to the aircraft's batteries, which in turn power the propulsion systems and the electro-optical equipment of the aircraft. The panels and the batteries have to be appropriately sized, in order to ensure that there is enough energy surplus available to power the vehicle during the night i.e. when the sunlight is absent." (Panagiotou, Tsavlidis, & Yakinthos, 2016). This implication of a solar power to supply energy to the vehicle is an interesting one since it could potentially allow for "eternal" flight of the craft, where it would only need to land for repairs and upgrades. 

The use of solar panels as the moment could not support the lift and thrust needed by military grade UAVs, for main the main circuit components of the craft, solar panels may be a great source for power. Yet for the main take off and continual movement of the vehicles this still would require the use of jet fuel. Though refueling of military drones is taking a turn to using unmanned systems. "In an in-air demonstration in 2007, DARPA teamed up with NASA to show that high-performance aircraft can easily perform automated refueling from conventional tankers., the successful test helped pave the way for future unmanned high-altitude long-endurance aircraft that can refuel in flight, expanding their mission capabilities and range." (DARPA, 2015)

(DARPA, 2015)

In flight refueling is needed for such drones as the Predator and the Global Hawk, yet for rotary wing UAVs (as the ones mostly used by civilian pilots) refueling is not needed but more of recharging the battery on board. Solar panels would be a prime use for continual flight, another idea is having the UAV return to a recharging station once the UAVs' battery drops to a certain percentage or to have the battery swapped out. This would remove the human involvement of bringing the UAV down and recharging the vehicle. 

(Junaid, Lee, & Kim, 2016)

This projected wireless recharging would allow for continual flight and less human intervention on the drones recharging itself. As technology increases and these refueling/recharging techniques so will the endurance and rate time of the UAVs mission. 

References: 

AeroWeb | MQ-1/MQ-9 predator/reaper. (2016, June 27). Retrieved November 13, 2016, from http://www.bga-aeroweb.com/Defense/MQ-1-Predator-MQ-9-Reaper.html

DARPA, Autonomous High Altitude Refueling. (2015). Retrieved November 13, 2016, from http://www.darpa.mil/about-us/timeline/autonomous-highaltitude-refueling 

Jonathan. (2016, March 2). Drones globe. Retrieved November 13, 2016, from Buying guides, http://www.dronesglobe.com/guide/long-flight-time

Junaid, A. B., Lee, Y., & Kim, Y. (2016). Design and implementation of autonomous wireless charging station for rotary-wing UAVs. Aerospace Science and Technology, 54, 253–266. doi:10.1016/j.ast.2016.04.023

Panagiotou, P., Tsavlidis, I., & Yakinthos, K. (2016). Conceptual design of a hybrid solar MALE UAV. Aerospace Science and Technology, 53, 207–219. doi:10.1016/j.ast.2016.03.023 

Research Blog 2: Unmanned Maritime Systems

Review on "A Concept for Docking a UUV With a Slowly

Moving Submarine Under Waves"

 The research for this week's blog, has brought me to unmanned underwater vehicles and their uses for the military and how they are deployed and retrieved by the vessel that houses the system. Unmanned underwater vehicles (UUVs) in military applications have been used or are in the planning stages for the following applications: Intelligence, surveillance, and reconnaissance, mine countermeasures, anti-submarine warfare, inspection/identification, oceanography, communication/navigation network nodes, payload delivery, information operations and time-critical strike. (Ervin 2014). Most of the UUVs are deployed and retrieved from a floating vessel above the water. The retrieval process in many cases are the same as the ABYSS AUV is retrieved: 

Retrieved from http://www.vosizneias.com/news/photos/view/493514038

"Once the scan is complete (roughly 20 hours or less)  the nose float pops off when triggered through an acoustic command. The float and the ca. 25 m long recovery line drift away from the vehicle so that a grapple hook can snag the line. The UAV is then brought aboard the vessel and the information is downloaded and analyzed.”(Linke & Lackschewitz, 2016). This retrieval system works well when the ship is stationary, above water, has the proper docking facilities, is not in a hostile region or an area with rough water that could possible damage the UAV or the ship when retrieving the vehicle. What if though a retrieval system was needed that could not fit the above criteria? This problem has been discussed in the Journal of Oceanic Engineering with the article title "A concept for docking a UUV with a slowly moving submarine under waves.": 

                            Docking an unmanned underwater vehicle (UUV) with a submerged submarine in littoral waters in high sea states requires more dexterity than either the submarine or streamlined UUV possess. The proposed solution uses an automated active dock to correct for transverse relative motion between the vehicles. Acoustic, electromagnetic, and optical sensors provide position sensing redundancy in unpredictable conditions. (Watt 2016).

Docking with a moving submarine does provide challenges, the UUV and dock must make physical contact precisely so that the UUV can be captured and parked. At the time being countries are in the process of developing methods for launching and recovering UUVs through torpedo tubes. This approach can work well in launching smaller UUVs for reconnaissance work, though retrieval with this approach is not fully discussed in this article, simulations of how recovery of these UUVs is discussed. " the active dock approach by using remotely operated vehicles (ROVs). This relies on operator control using video feedback and is probably time consuming, but it provides flexibility and minimizes docking infrastructure on the UUV itself." (Watt 2016)

There are however limitations with this recovery system. One is that the size of the UUV has to be smaller than the torpedo tube, also with the UUV being small the endurance and the payload would be less, making the UUV have to continuously be returned, charged and resent constantly. This increases work and cost that would be offset by creating a larger UUV which would have a larger payload and endurance. The other problem that could come from this is the occupation of the torpedo tubes. If the submarine has been outfitted to become a research vessel then there is no problem in this. Yet if the submarine is being used for wartime efforts, having one or more of the torpedo tubes occupied could mean the difference between life and death of the crew on the submarine. This is where the idea from this article comes into play. A docking system located on the underside of the submarine, this would allow for a larger UUV to be deployed also this would free the torpedo tubes to be used for their mandated purpose.

The process of docking while forward movement has 3 benefits:
"1) Submariners prefer to keep moving and submarines are designed to do so quietly at low speed. Hovering, the deep water stationary docking alternative, is a potentially noisy operation relying on pumps and will lose effectiveness under high sea states.

2) Constant forward speed throughout the docking process reduces the impact of environmental disturbance by superposing a stabilizing steady velocity component on the disturbance and by providing hydrodynamic control for both the UUV and submarine. Although hydrodynamic control for submarines at the top speeds of many commercial grade UUVs (2 m/s) is not great, it is better than at zero speed.

3)With stationary docks, failed docking attempts require the UUV to ‘go-around’ to try again, a lengthy process,whereas when both vehicles are moving in parallel a simple speed adjustment by the UUV can quickly reset conditions for a new docking attempt." (Watt 2016)

Docking is perceived in the following figure: 

(Figured obtained from Watt 2016)

To wrap up this discussion, the use of a full docking unit attached to the bottom of the submarine while in forward motion to dock with the UUV as it too moves in the forward motion would be beneficial to launch a recover a UUV. The only problem that I can see with this is loss of the UUV if damage was done to the docking port by either rough water or unforeseen underwater terrain and organisms that could attach themselves to the docking port. 

                    

References: 

Ervin, W. P., Madden, P., & Pollitt, G. W. (2014). Unmanned Underwater Vehicle Independent Test and Evaluation. APL Technical Digest, 32

Linke, P., & Lackschewitz, K. (2016). Autonomous underwater vehicle „ABYSS“. Journal of large-scale research facilities JLSRF, 2, . doi:10.17815/jlsrf-2-149

Watt, G. D., Roy, A. R., Currie, J., Gillis, C. B., Giesbrecht, J., Heard, G. J., . . . Jeans, T. L. (2016). A concept for docking a UUV with a slowly moving submarine under waves. IEEE Journal of Oceanic Engineering, 41(2), 471-498. doi:10.1109/JOE.2015.2424731