This blog has been created for use during my advanced studies in Aeronautics, Unmanned Systems, and Polymer Matrix Composite Materials. (Along with some random "fun" topics.)

Saturday, August 20, 2016

UAS - Levels of Autonomy

     UAS integration into the National Airpsace system continues to be a long and daunting road with plenty of twists and turns.  A variety of technologies continue to be researched and developed but with no overall standard due to a multitude of technological alternatives as well as barriers.  The changing landscape saw some light at the end of the tunnel with the recent release of Part 107, which applies to small unmanned aircraft for commercial operation.  The sUAS market has begun to grow and is predicted to generate more than $82 billion for the US economy and create more than 100,000 jobs over the next 10 years.   Due to the lower cost of such platforms, ease of access, vast number of applications, and the new FAA regulations, the commercial sUAS industry  could potentially grow more rapidly than any other area.  However the integration of such platforms in the NAS still leaves a few gaps to be filled such as the challenges of autonomy.

     Levels of Autonomy and factors affecting it can vary based on the UAS platform and environment.  Even most UAS used in the military aren’t fully autonomous.  Defining the threshold at which operator intervention and system automation takes hold is still a challenge.  An effective human-automation interaction level must be defined along with trust and mode awareness.  UAS automation roles and responsibilities are still being defined.  An example of the differences in definitions can be shown below in figure 1.  Three different sources and their associated definitions for levels of autonomy shown below gives some insight into the issue. 

                                  Figure 1 - Levels of Autonomy 

     NextGen is a big proponent for utilizing autonomous methods for safely controlling UAS in the NAS.  However, at what level will automation help with self separation, sense and avoid, lost link, and other pilot/aircraft interaction automated assistance.  Research continues to be ongoing for testing automated systems such as NASA’s Ikhana Predator B to determine the level of autonomy that can help in avoiding other air traffic in the NAS.

     Ironically, per Part 107 and the use of small UAS which is considered less than 55 lbs. autonomy isn’t part of the picture.  Flying must be conducted within line of sight, during daylight hours, at a maximum altitude of 400 feet, operations in B, C, D and E airspace is allowed with ATC permission, but under normal circumstances must be 5 miles from the nearest airport.   In addition, FAA airworthiness certification is not required.  Even though autonomy does not play a direct role in this type of commercial integration, the types of UAS platforms under 55 lbs offer some of the latest technology including high levels of automation based on flight controller types.  Many current off the shelf UAS can take-off, land, and fly pre-programmed flights similar to how the military would carry out a UAS type mission, just at a higher altitude and longer range.  Some UAS even offer autonomy options with the ability to follow an object or person, as well as avoid obstacles based on size, distance, and lighting. 

     As the commercial sUAS industry begins to grow more rapidly types of automation used on such platforms will increase as they already have to help the pilot in command.  Automation technologies used on sUAS have the ability to grow more rapidly due to the vast number of applications they can be used on and consumer level pricing.  Along with R&D from NASA and the DOD, actual sUAS platforms being used per part 107 will also help shape and define the future levels of autonomy integrated within the NAS.  However, regulations governing such automation to insure safe flight may have a hard time keeping up with the fast paced technologies.  

  
  
References

Anderson, J.  (2010).  Challenges in Autonomy.  Retrieved from https://www.k-state.edu/ckus/conference/abstract_titles/AndersonChallenges.pdf

FAA.  (2016). FAA News.  Retrieved from https://www.faa.gov/UAS/media/Part_107_Summary.pdf

NASA.  (2013).  NASA – UAS Integration in the NAS.  Retrieved from file:///C:/Users/Jason_000/Downloads/NASA_SBIR_amp_STTR_Program_Homepage_-_UAS_Integration_in_the_NAS_-_2013-10-31.pdf


Saturday, August 13, 2016

UAS Strengths and Weaknesses - Military Vs. Civil


Civil use of Unmanned Aerial Systems has been met with angst from many groups due to association of the technology with the department of defense and other government operations. Ironically, some of the most used civilian technologies today have come from the defense side such as GPS, Radar, Microwaves, Nylon, canned foods, advances in air travel, duct tape, computers, and now “drones”. Below shows a diagram of UAV mission types related to civil applications. To limit UAS platforms to military only operations would be narrow sited considering the advantages they offer to the industries and applications shown below.

 
                                                Figure 1 - Civil Applications
 

Military UAS missions almost always take advantage of some form of remote sensing. Examples of active and passive sensor types include LIDAR, photoscanning, thermal imagery, active microwave, stereovision, hyperspectral, and ultrasonic to name just a few. The greatest advantage in the advancement of sensor types for military use is the ability to detect energy and radiation outside visible light of the electromagnetic spectrum. Energy can be reflected, absorbed, or emitted. An example of this would be the Aces Hy Hyperspectral Sensor on the Predator drone used in Afghanistan. The sensor allows detection of electromagnetic radiation other than what's discernible by the human eye such as hidden roadside bombs or opium crops. The sensor basically detects the composition of an object based on its spectral fingerprint.


                                               Figure 2 - Hyperspectral Imaging
 
Another military remote sensing application would be the HALOE which is a LIDAR sensor used on the Firescout (unmanned helicopter). LIDAR allows for scanning of space to create a 3D map of ground terrain through the use of “time of flight”. HALOE or High Altitude Lidar Operations Experiment has already been flown in Afghanistan as well. This has allowed for more than a third of Afghanistan to be mapped with the ability to also detect “pirates” at sea when using the Firescout. The disadvantages of such sensors can be the cost, maintenance, and operating environment in which they can be used. The sensor packages must be ruggedized when entering certain harsh environments. Also some sensors require specific weather conditions to return optimal image data. Cost can be reduced as sensor technologies improve and quantities increase.
 
 
                                                            Figure 3 - LIDAR Image


The remote sensing applications above carry over directly to civil uses and one unique example of this is civil engineering. Civil Engineering deals with land surveying, structural health monitoring, and ground/structure mapping during the design and construction phase of a project. Photoscanning/LIDAR through the use of UAS allows for a company or firm to shows the condition of an existing project through 3D rendering versus standard aerial photos which are not as accurate, especially when trying to utilize photogrammetry techniques. Once a 3D model has been generated a 3D fly-through of the environment is possible giving the greatest perspective possible. In addition to capturing the actual structure the surrounding terrain would also be captured to help in planning for a project.


The cross over of remote sensing from military to civil applications should be no surprise and even though the cost of some sensors can be high, overall for civil applications this is a huge cost reduction compared to manned aircraft. However, sensor cost is slowly declining as well. In addition, manned aircraft are not capable of certain tasks that UAS platforms are, while doing it at a fraction of the cost. Mapping technologies will continue to grow for civil applications due to the growing demand in various industries and the cost savings over mapping with manned aircraft. Lessons learned from the military once again will play a major role in UAS remote sensing technology but as civil applications increase, they will also play a major role in the technologies direction and usage.



References

Campbell, J. B., & Wynne, R. H. (2011). Introduction to remote sensing, fifth edition (5th;5; ed.). US: Guilford Publications Inc. M.U.A.

Irilluminators. (2014). Hyperspectral Imaging with Infrared Light. Retrieved from https://irilluminators.wordpress.com/2014/01/24/hyperspectral-imaging-with-infrared-light/

Johnson, C. (2013). Civil Use of UAS, A Little More Light , Please. Retrieved from http://www.insidegnss.com/node/3491

NASA. (2004). Civil UAV Capability Assessment. Retrieved from https://www.nasa.gov/centers/dryden/pdf/111761main_UAV_Capabilities_Assessment.pdf

Perlman, A. (2015). Applications for UAV’s in Civil Engineering. Retrieved from http://uavcoach.com/applications-for-uavs-in-civil-engineering/

Wweinberger, S. (2012). 4 Done Sensors That Changed Warfare – and What Happens when they Come Home. Retrieved from http://www.popularmechanics.com/military/g1741/4-new-drone-sensors-that-changed-warfare-and-what-could-happen-when-they-come-home-9549377/?slide=1



Open Hole Compressive Strength of Polymer Matrix Composite Laminates

The link below outlines the steps I have summarized per ASTM for open hole compressive strength testing of polymer based composite laminates.


Open Hole Compressive Strength Testing