Wednesday, April 30, 2014

Search and Rescue UAVs




UAS are very well suited to the Search and Rescue mission.  The availability of small but highly capable UAV systems will make this job much safer for the rescuers and potentially make it much easier and faster to find the victim possibly saving more lives. “UAS can provide situational awareness over a large area quickly, reducing the time and the number of searchers required to locate and rescue an injured or lost person, greatly reducing the cost of search and rescue missions. They can be the first eyes in the sky – immediately after an incident, letting first responders know precisely where to direct resources. The possibilities for helping ensure public safety are endless.”("AV," 2014, p. 1)
For this type of mission small, man portable systems would be most useful.  This would allow rescuers to carry the system with them and deploy it as need and be able to self-recover the UAV for later use.  The Raven B DDL UAS by AeroVironment would be an ideal system for this type of application.  It is small, light (4.8 lbs.), and launched by hand making this system easily packed into and used in difficult terrain as demonstrated by the military in Afghanistan and Iraq. A UAV that is particularly suited to Search and Rescue missions would the quadcopter type UAS.  Many of these systems are available as RC class aircraft to much more sophisticated systems such as the AeroVironment’s Qube quadcopter.  “With its impressive 40-minute flight endurance, built-in safety features and intuitive user interface, Qube provides the ability to make command decisions without putting humans in harm’s way. Qube is the ideal solution for missions where time is short and risk is high protecting lives and property.”("Qube," 2014, p. 1)  The Mesa County Arizona Sheriff’s Department has been using a small unmanned helicopter and a hand launched fixed wing UAV since 2010. This has provided the department with a lot of capability for a fraction of the cost of a manned helicopter traditionally used in Search and Rescue. “The direct operational cost, including replacement parts and electricity to charge the drones, totals $3.36 an hour.”(Ban, 2012, p. 1)
UAVs provide the capability for very small law enforcement departments, civilian organizations, and even volunteer units the ability to have capabilities that were very limited and only available to the largest departments in the past. There are challenges however, the largest being getting permission from the FAA to fly these aircraft.  During the 2013 flooding in Colorado a small UAV manufacturer volunteered to use it UAV to help search for survivors when manned military aircraft were not able to fly and were told to cease operations by the FAA.  Many of the UAV systems used for this type of application are small RC type aircraft and the NTSB has recently ruled that the FAA does not have jurisdiction over this class of aircraft which could open the door for more of these operations to start flying.  There is also significant reluctance in the population for the use of UAVs by law enforcement and other civil organizations over fears of privacy violations.  While most of these fears are unfounded and are born of ignorance they do however represent a significant hurdle to future operations.
While UAVs will have many civil applications I feel that Search and Rescue will be one of the first civil missions that UAVs will be used in.  The fact that most of these missions will take place over unpopulated or sparsely populated areas will make it easier to obtain FAA permission to fly in the NAS.  Also this mission is more palatable to the public than general law enforcement use and as stated they generally use smaller man portable or RC class systems that will most likely be the first cleared to fly in the NAS.


References

Thursday, April 17, 2014

Activity 4.4

Separation of unmanned aircraft or See and Avoid capability is a crucial link in allowing routine use of Civil and Military UAS in the National Airspace (NAS).  While UAS have better situational awareness of their exact location at any given time than most manned aircraft their lack of ability to see and avoid other aircraft in real time is a major hurdle needs to be overcome.(Integration, 2013)  Currently there are two systems under development to help alleviate this problem.  General Atomic s is developing an air based sense and avoid system while the U.S. Army is developing a ground based sense and avoid system.  Manned systems have systems to assist with issue as well while flying in IFR (Instrument Flight Rules) such as TCAS (Traffic Collision Avoidance System), ADS-B (Automatic Dependent Surveillance Broadcast), and Mode 4 transponder.

The U.S. Army has chosen a GSAA (Ground Based Sense and Avoid) system to avoid increasing electrical loads and increasing aircraft weight.  This is definitely a benefit for smaller systems such as the RQ-7 Shadow and MQ-5 Hunter.  This system is capable of use with SUAS systems such as the Raven and WASP AE but will generally not be needed sense these systems are flown within sight of the operator.  This system has been successfully tested by the Army and FAA and will went into service starting in March 2014. (Lee, 2014)

The General Atomics air based SAA (Sense and Avoid) system is completely on the aircraft and consists of a radar (Due Regard), transponder (ADS-B), and traffic alert (TCAS) system.  The DRR (Due Regard Radar) will be able to actively track all other aircraft in the area even if the other aircraft does not have a transponder or any electrical systems at all. The ADS-B system in the transponder sends GPS location information of the aircraft to all other aircraft in the area.  The TCAS works with the transponder as well to give traffic collision and proximity warnings.  This system has had successful tests completed late last year and will continue testing to get full approval from the FAA. ("General Atomics," 2014)


Each of these systems has strengths and weaknesses as well as platform suitability issues but with the availability of both systems this will allow manufacturers and users to choose which system is the best option for their platform.


References



Thursday, April 3, 2014



In this situation as the systems engineer I would go to both teams and talk to them about their limitations and if necessary how they could reduce weight without reducing performance.  I would speak to each team about their decision making and make it clear to them that meeting customer demands and the performance that has already been promised is the number one goal. I would also state that cutting the safety margin is not an option. Using UAS for commercial purposes is an emerging field and one of the main concerns is UAS safety. If safety margins are cut to save a little time or money now and an accident occurs that causes property damage or injury or death to a person then the whole program will be shut down. Worse, UAS development and regulatory resolutions will most likely be put on a lengthy hold.

With these considerations in mind I would make it clear that reducing performance as previously promised is not an option. In this case I would focus on customizing the Guidance, Navigation, and Control systems to reduce weight. I would also pursue any possibility in modifying the payload system to reduce weight as long as it did not affect performance. I would tell both teams that reducing fuel load and therefore safety margin is not an option. I would then work with both teams to help solve their issues.

A major learning point from this would be finding a better way to make a new improved version of the system. This will allow us to know through experience what can be used from “off the shelf” components and what needs to be custom made for the system. Since this is an emerging field customer satisfaction and customer loyalty will be of paramount importance. As the old saying goes, you only get one first impression. If performance promises are not met or safety is compromised customers will not return for future products. Hopefully by using these lessons learned the newer model will be able to not only meet requirements but significantly exceed them. (Terwilliger, Burgess, & Hernandez, 2013)


 

References