Request for Proposal

            This study fulfills the requirements for the design of an unmanned aerial system to support emergency management in response and recovery efforts of a natural disaster, such as a tornado, hurricane and wildfires. The unmanned aerial system is based on the high-level base requirements provided to the class.  In this paper, a series of derived/low-level requirements for the design of the UAS to the element level is discussed to support response and recovery efforts. 

            This study will analyze three of the seven elements of the UAS design: the air vehicle, command and control, and payload. The other important elements such as transportation, cost, datalink and support equipment, although equally important elements for a complete system are not discussed in this paper. Notional testing requirements to verify the system are proposed. The schedule to perform the required phases of development (e.g., system development, ground testing, and in-flight testing) is discussed in general terms. 

In the study, the surveillance and mapping missions are chosen as examples among the many tasked that can be performed by an aerial vehicle in support of an incident response.  This aerial vehicle will help assess the situation during the recovery phase.  In response to the high level base requirements, a selection of a multi-rotor airframe is selected.  Although the one-hour endurance is a challenge, there are several capable airframes on the market that can meet this requirement.  The surveillance mission requires a capable electro-optic and infrared camera as the primary payload. The daylight camera can also provide still images which can be stitched together to provide useful maps. It will assist in detecting changes in the environment caused by the incident.  

The timeline for developing this project should not take more than six months.  Most of the components including the vehicle are based on commercially-off-the-self technologies.  There will be some customization to integrate all the components into the vehicles. The EO/IR camera gimbal needs to be built and customized for this application.  The hyperspectral will be a commercial product, which is a plug and play module.

Overview

            The high-level base aerodynamic design considerations for this aerial vehicle require that this aircraft be capable of flying 500 feet with sustained flight in excess of one hour, covering a radius of one mile.  The payload considerations of color daytime and infrared (IR) video up to 500 feet AGL.  The other high-level base requirements are addressed in the three elements of designed: the air vehicle, command and control, and payload.

The aerial vehicle chosen for this requirement is the Phoenix ACE LE Pro built by UAV Solutions of Jessup, Maryland.  This aircraft shown in Figure 1 is new to the market, as it debuted at the 2016 AUVSI Xpodiential in New Orleans in May 2016 (Phoenix ACE LE Pro) .  By using this basic aircraft system, the design, building, and testing of the integrated solution can be accelerated. 

Figure 1. ACE LE Pro

The payloads for this aerial vehicle need to be small since it affects the size weight and Power (SWaP) configuration of this basic airframe.  Maintaining the one-hour endurance will be the most pressing challenge in the built.  As such, the payload will be a Sony 10X zoom electro-optic camera and a FLIR 336 Infrared (FCB-EV7100 Camera Block, n.d.; FLIR 336 IR, n.d.).  Both cameras shown in Figure 2 are designed as small lightweight form factors, but with significant capabilities. For the mapping missions, Pix4D software can be used to generate two and three dimensional models of the areas of interest.

                            

Figure 2.  Sony 10X and FLIR 336 IR. (Retrieved from Sony and FLIR websites.)

The gimbal is a custom designed manufactured using a 3D printer. The intent is to reduce weight while providing a three (2) degrees of freedom as shown in Figure 3. 

                                                      

Figure 3.  Gimbal assembly

The command and control element is an open source solution using an Pixhawk autopilot and Ardupilot Command Module Software.  By using an open source solution, the end user will be able to modify the software to his preferences.  The use of this open source autopilot also reduces risk to the project, as it well used in many types of unmanned systems.  The communications radios to meet the requirements are not so stringent. A COTS solution based on the 3DR radios is appropriate.  

Major Base Requirement Categories (Notional)

            In this section of this study, a breakdown of the proposed series of derived/low-level requirements for the design of the UAS is provide for: the air vehicle element; command and control; and payload.  These are notional representative design elements.  In reality a more extensive list would be used.

Air Vehicle Element

3. Air Vehicle Element –

3.1 Shall be capable of flight up to 500 feet altitude above ground level (AGL)

3.1.1 [Derived requirement] - Electric motors shall provide sufficient lift to

achieve flight at 500 AGL.

3.1.2 [Derived requirement] - Batteries shall provide electric power to achieve a

one-hour endurance at 500 feet altitude. 

3.2 Shall be capable of sustained flight (at loiter speed) in excess of one hour

3.2.1 [Derived requirement] - Batteries shall provide electric power to achieve a

one-hour endurance at loiter speed. 

3.3 Shall be capable of covering an operational radius of one mile

3.3.1 [Derived requirement] – Radios shall have enough power to transmit and

receive signal greater than one mile.

3.3.2 [Derived requirement] – Autopilot must be able to control aircraft at

distances of at least one mile. 

3.4 Shall be deployable and on station (i.e., in air over mission area) in less than 15

minutes

3.4.1 [Derived requirement] - Aircraft shall be modular in design so that can be

put together less than 10 minutes.

3.4.2 [Derived requirement] – Command and control computer shall be

operational in 10 minutes

3.4.3 [Derived requirement] – Aircraft shall be able to fly to a one-mile radius at

500 feet within 5 minutes of deployment.

3.5 Shall be capable of manual and autonomous operation

3.5.1 [Derived requirement] – Autopilot system shall be capable of manual and

autonomous operations

3.5.2 [Derived requirement] – Control module shall be capable of autonomous

operations.

3.5.3 [Derived requirement] – Hand controller shall be capable of manual

operations.

3.6 Shall provide capture of telemetry, including altitude, magnetic heading,

latitude/longitude position, and orientation (i.e., pitch, roll, and yaw)

3.6.1 [Derived requirement] Command Module shall be capable of capturing all

metadata from the aircraft internal (autopilot) and external sensors (GPS).

3.7 Shall provide power to payload, telemetry sensors, and data-link

3.7.1 [Derived requirement] - Batteries shall have enough electric power to

provide for the payload, telemetry sensors and data-link.

3.8 Shall provide capability to orbit (i.e., fly in circular pattern around) or hover over an

object of interest

3.8.1 [Derived requirement] – Autopilot shall be able to receive commands from the

Command Module to conduct preprogrammed maneuvers such as orbits, and hovers over

a reference position.

3.8.2 [Derived requirement] – Command Module shall be able to send preplanned

commands to the aircraft.

Command & Control (C2)

4. Command & Control (C2) -

4.1 Shall be capable of manual and autonomous operation

            4.1.1 [Derived requirement] - Command Module shall be able to send manual or

autonomous commands to the aircraft.

4.2 Shall provide redundant flight control to prevent flyaway

4.2.1 [Derived requirement] – Command Module shall be able to program the

autopilot via various modes of operations to prevent a flyaway.

4.2.2 [Derived requirement] – Command Module shall contain Fail-Safe

modules to prevent flyaway.

4.3 Shall visually depict telemetry of air vehicle element

4.3.1 [Derived requirement] – Command Module shall have a common operating

picture with a dashboard to display the air vehicles telemetry data.

4.4 Shall visually depict payload sensor views

4.4.1 [Derived requirement] - Command Module shall have a common operating

picture with a dashboard to display payload sensor views.

Payload

5. Payload

5.1 Shall be capable of color daytime video operation up to 500 feet AGL

                       5.1.1 [Derived requirement] – The Sony FCB-EV7100 camera shall have the proper                lens to provide 1meter resolution at 500 feet AGL

5.2 Shall be capable of infrared (IR) video operation up to 500 feet AGL

5.2.1 [Derived requirement] – The FLIR 336 IR shall be capable of detecting a

person at 500 feet AGL.

5.3 Shall be interoperable with C2 and data-link

5.3.1 [Derived requirement] – The cameras shall be interoperable with the

Command Module software and data link communications.

5.4 Shall use power provided by air vehicle element

5.4.1 [Derived requirement] – Batteries shall be able to provide power to the

payload for a one-hour flight duration.

Testing Requirements (Notional)

            This section is a notional listing of testing elements for the vehicle, command & control, and payload.

Air Vehicle Element

6. Air Vehicle Element –

6.1 Endurance

6.1.1 Test batteries with full load until minimum acceptable level of voltage is

available to the loads

6.1.2 Fly aircraft at 500 feet (at loiter speed) for until battery reaches lowest

acceptable level.

6.2 Command and control

6.3.1 Conduct testing to determine maximum distance between radios

6.3.2 Test Autopilot with aircraft distances greater than one mile. 

6.4 Deployment times

3.4.1 Verify that the aircraft can be put together less than 10 minutes.

6.4.2 Verify that the command and control computer can be operational in less

than 10 minutes.

6.4.3 Verify that aircraft can be at least one-mile from launch site at 500 feet

within 5 minutes of launch.

6.5 Manual and autonomous operation

6.5.1 Test Autopilot system in manual and autonomous operations

6.5.2 Test control module in autonomous operations.

6.5.3 Test hand controller in manual operations.

6.6 Metadata

6.6.1 Verify that the command module captures all metadata from the aircraft internal

(autopilot) and external sensors (GPS) to include: altitude, magnetic heading,

latitude/longitude position, and orientation (i.e., pitch, roll, and yaw)

6.7 Electrical Distribution

6.7.1 Test electrical distribution and batteries to provide electrical power to the payload, telemetry sensors and data-link.

6.8 Flight testing

6.8.1 Test autopilot to receive commands from the Command Module to conduct

preprogrammed maneuvers such as orbits, and hovers over a reference position.

6.8.2 Test command module shall be able to send preplanned commands to the aircraft.

Command & Control

7. Command & Control (C2)

7.1 Manual and autonomous operation

            7.1.1 Verify Command Module be able to send manual or autonomous commands to the aircraft.

7.2 Redundant flight control to prevent flyaway

7.2.1 Verify Command Module be able to program the autopilot via various

modes of operations to prevent a flyaway.

7.2.2 Verify Command Module contains FailSafe modules to prevent flyaway.

7.2.3 Test Command Module FailSafe modules which prevent flyaway.

7.3 Visual Displays

7.3.1 Verify Command Module has a common operating picture with a dashboard

to display the air vehicles telemetry data.

7.3.2 Verify Command Module has a common operating picture with a dashboard

to display payload sensor views.

Payload

8.  Payload

8.1 Color daytime video

8.1.1 Verify the Sony FCB-EV7100 camera has the proper lens to provide 1meter

resolution at 500 feet AGL

8.2 Infrared (IR) video

8.2.1 Verify The FLIR 336 IR shall be capable of detecting a person at 500 feet

AGL.

8.3 C2 and data-link

8.3.1 Verify the cameras are interoperable with the Command Module software

and data link communications.

8.4 Endurance

8.4.1 Verify the batteries shall be able to provide power to the payload for a one

hour flight duration.

Processes, Schedules and Testing

Development Process

            In this project there are numerous components that need to be integrated.  There are numerous subsystems that need to be built.  It is appropriate to use the waterfall sequence approach as proposed by the Fairfax County Department of Information Technology (2003).  The waterfall sequence approach shows the interrelationship between the elements in a format to quickly assess the progress of the project. 

Schedules

            In this project, several subtasks are incremental developments that achieve an integrated solution. By using the incremental development approach problems with the subcomponents can be detected sooner, avoid cost to fix problem areas.  It also provides the program managers useful feedback on the timeline for subsystem completion.  If this project results in additional units, the incremental development approach provides a better architecture to be able to incorporate lesson learned through documentation (System Development Life Cycle Standards, 2003).

Testing

            Testing occurs throughout the project at the component, subsystem, and integration testing. Documentation is critical to ensure traceability of the processes. One way to ensure proper documentation throughout the manufacturing and flight testing is to use a web based software package, such as is demonstrated in the University of Manchester UAV design process and testing video from the Module 7 multimedia review.  Using solutions such as in the Manchester examples ensures that all the testing is done in a structured matter, with traceability within the process. 

Design Decisions

            The selection of the vehicle and components to meet the stated requirements were based on using commercially available components. The vehicle is fairly basic, yet robust in construction.  Even though the camera solution is custom, the components are commercially available from outstanding vendors, Sony and FLIR.  The construction of the gimbal using a 3D printer reduces costs, while providing a light weight solution. 

The open sources command and control components include; the autopilot, radios, firmware and graphics user interface.  They are available from any hobby shop, but are considered of a high enough quality to meet the client’s requirements.  This open source approach allows the client to modify the software to meet their particular desires. 

Since the components are all available from known vendors, the integration of this solution should not be delayed by availability of components. It should be a quick built and enough time to provide an extensive testing period at the manufacturing facility, as well as, at an approved testing site. 

References

ArduPilot Autopilot Suite. (n.d.). Retrieved September 23, 2016, from http://ardupilot.com/ardupilot/index.html

FCB-EV7100 Camera Block. (n.d.). Retrieved September 23, 2016, from https://pro.sony.com/bbsc/ssr/cat-camerasindustrial/cat-ciblockcameras/product-FCBEV7100/

FLIR 336 IR Quark Uncooled Cores. (n.d.). Retrieved September 23, 2016, from http://www.flir.com/cores/display/?id=51266

Phoenix ACE LE Pro. (n.d.). Retrieved September 23, 2016, from http://uav-solutions.com/phoenix-ace-le-pro/

Pix4D - Drone Mapping Software. Retrieved September 24, 2016, from https://pix4d.com/

System Development Life Cycle Standards [PDF]. (2003, July). Fairfax, VA: Fairfax County Department of Information Technology.