Incident commanders are the personnel responsible for
coordinating responses to disasters or searches. Access to a UAS that can
search a large area and return data for both tactical decisions and detailed
analysis can greatly aid the success of a search/response mission. This UAS is
designed for use by a quick response team in a rural or wilderness setting.
Given the high-level baseline requirements for the air
vehicle element, the datalink, and total cost, the following derived
requirements and testing requirements have been developed. Following the
derived requirements and testing procedures, a small fixed-wing tactical UAS specific
to search and rescue operations could be developed in about one year.
Proposed Requirements
A.
Air vehicle element
1.
Shall be capable of flight up to 500 feet
altitude above ground level (AGL)
1.1. Aircraft
design shall facilitate steady climb to assigned altitude, up to and including
500 feet AGL
1.1.1.
Verify aircraft reaches 500 feet AGL in manual
control mode
1.1.2.
Verify aircraft maintains assigned altitudes in
autonomous flight control mode
1.1.3.
Record aircraft speeds:
1.1.3.1.
Determine Vx
1.1.3.2.
Determine Vy
1.1.3.3.
Determine Vmc
1.1.3.4.
Determine Vs1
1.1.3.5.
Determine Vso
1.1.3.6.
Determine Vne
1.1.4.
Verify minimum aircraft speeds for each phase of
flight
1.2. Aircraft
flight weight and balance envelope shall include scenarios for all phases of
flight
1.2.1.
Verify aircraft forward CG does not negatively
impact climb performance
1.2.2.
Verify aft CG does not negatively impact stall
recovery
1.2.3.
Verify nominal CG does not negatively impact
performance in high wing loading conditions
1.3. Payload
performance shall meet minimum visual standards at 500 feet AGL
1.3.1.
Verify visual detection test with payload
imagery from 500 feet AGL
2.
Shall be capable of sustained flight (at loiter
speed) in excess of one hour
2.1. Battery
capacity shall meet system electrical load analysis plus powerplant load for 1
hour plus 20% endurance
2.1.1.
Perform powerplant electrical load analysis for
all phases of flight
2.1.2.
Perform airframe electrical load analysis for
all phases of flight
2.1.3.
Verify battery discharge rate meets manufacturer
specification for calculated electrical load analysis
2.1.4.
Verify battery capacity meets manufacturer specification
for discharge time (measured in mAh)
3.
Shall be capable of covering an operational
radius of one mile
3.1. Datalink
shall be capable of communication range exceeding two miles (per B.1.1)
3.1.1.
Perform primary datalink range test
3.1.2.
Perform secondary datalink range test
3.2. Payload
signal transmission power shall reach two miles (per B.1.4)
3.2.1.
Perform full-motion video range test
4.
Shall be deployable and on station (i.e., in air
over mission area) in less than 15 minutes
4.1. Aircraft
speed must be greater than speed that reaches 2 mile range while permitting
deployment of system within 15 minutes
4.1.1.
Determine system assembly/emplacement time
4.1.1.1.
Verify accuracy of system emplacement checklist
to determine time-saving procedures
4.1.1.2.
Verify accuracy of aircraft launch checklist to
determine time-saving procedures
4.1.2.
Verify aircraft dash speed at nominal mission
weight
5.
Shall be capable of manual and autonomous
operation
5.1. Control
system shall include teleoperation control mode
5.1.1.
Verify aircraft control surface movement with
remote controller
5.2. Control
system shall include GPS waypoint navigation mode
5.2.1.
Verify aircraft control surface movement with
programmed waypoint navigation
5.3. Control
system shall include semi-autonomous stabilized teleoperation mode
5.3.1.
Verify opposite aircraft control surface movement
while aircraft is moved about axis
5.4. Autonomous
control mode shall permit dynamic re-tasking
5.4.1.
Verify mission control software features
point/click waypoint assignment in flight modes
5.4.2.
Verify aircraft flight performance when active
waypoint is moved or changed
5.5. Autonomous
control mode shall permit manual GPS waypoint entry
5.5.1.
Verify mission control software features manual
waypoint latitude/longitude entry
5.6. Autonomous
control mode shall include return-to-home mode in case of control link loss
5.6.1.
Verify proper aircraft performance with induced
link loss
5.7. Autonomous
control mode shall include dead reckoning mode in case of GPS signal loss
5.7.1.
Verify proper aircraft performance with
simulated loss of GPS signal
6.
Shall provide capture of telemetry, including
altitude, magnetic heading, latitude/longitude position, and orientation (i.e.,
pitch, roll, and yaw)
6.1. Ground
control system display shall include primary flight display
6.1.1.
Verify status of PFD reports during all phases
of flight
6.2. Ground
control system display shall include moving map display with position of
aircraft and programmed waypoints
6.2.1.
Verify aircraft position during all phases of
flight
6.3. Ground
control system shall record telemetry to local hard drive
6.3.1.
Verify list of recorded parameters for accuracy
6.4. Autopilot
shall record telemetry to local storage
6.4.1.
Verify recorded parameters match recorded ground
control station telemetry
7.
Shall provide power to payload, telemetry
sensors, and data-link
7.1. Payload,
telemetry sensors, and communication transceivers shall be connected to the same
power source
7.1.1.
Verify electrical system continuity
7.2. Power
source load analysis shall provide capacity for payload, sensors, and
transceivers
7.2.1.
Verify payload operation with power applied
7.2.2.
Verify telemetry sensor operation with power
applied
7.2.3.
Verify datalink transceiver operation with power
applied
7.2.4.
Verify all electrical equipment operation with
full system load
8.
Shall provide capability to orbit (i.e., fly in
circular pattern around) or hover over an object of interest
8.1. Autonomous
control modes shall include option to loiter around fixed point
8.1.1.
Verify aircraft performance in loiter mode,
turns to left
8.1.2.
Verify aircraft performance in loiter mode,
turns to right
8.2. Autonomous
control modes shall include option to alter loiter radius
8.2.1.
Verify aircraft performance when loiter radius
is changed
8.3. Loiter
position over POI should be able to be manually entered via latitude/longitude
8.3.1.
Verify proper aircraft response when new POI
loiter is assigned
B.
Data-link (communications)
1.
Shall be capable of communication range
exceeding two miles visual line of sight (VLOS)
1.1. See
A.3.1
1.2. Airborne
datalink transceivers shall transmit sufficient power
1.2.1.
Bench test transceiver transmitted power
1.2.2.
Bench test transceiver system impedance
1.2.3.
Bench test antenna gain
1.2.4.
Bench test antenna impedance
1.2.5.
Verify installed system VSWR values
1.3. Ground-based
datalink transceivers shall transmit sufficient power
1.3.1.
Bench test transceiver transmitted power
1.3.2.
Bench test transceiver system impedance
1.3.3.
Bench test antenna gain
1.3.4.
Bench test antenna impedance
1.3.5.
Verify installed system VSWR values
1.4. Ground
support equipment shall include a high-gain tracking antenna based on aircraft
GPS position
1.4.1.
Verify operation of antenna tracking with
aircraft movement
1.5. Full
motion video signal shall be visible at two miles VLOS
1.5.1.
Bench test video transmitter power
1.5.2.
See A.3.2.1
2.
Shall provide redundant communication capability
(backup) for C2
2.1. COTS
transceivers shall be re-certified for reliability
2.1.1.
Verify primary datalink reliability in nominal
operating environment
2.1.2.
Verify secondary datalink reliability in nominal
operation environment
2.2. Primary
datalink transceiver shall transmit in FCC ISM band
2.2.1.
Verify transceiver channel selectivity
2.2.2.
Verify transceiver bandwidth at nominal data
transmission baud rate
2.3. Secondary
datalink transceiver shall transmit in FCC amateur band
2.3.1.
Verify transceiver channel selectivity
2.3.2.
Verify transceiver bandwidth at nominal data
transmission baud rate
2.4. Datalink
transceiver signal shall not degrade telemetry sensor accuracy
2.4.1.
Bench test telemetry sensor accuracy with all
transceivers transmitting full power
3.
Shall use power provided by air vehicle element
3.1. (Same as A.7.1)
C.
Cost
1.
Shall be less than $100,000 (equipment cost
only)
1.1. System
deliverable shall include bill of materials (BOM) detailing COTS pricing
1.1.1.
Verify complete price list of all deliverables
1.2. BOM
shall include cost of raw materials
1.2.1.
Capture specific market price reflected in BOM
Development Process
Phases:
1.
System Development: 12 weeks
a.
Concept Design
i. 4
weeks
b.
Concept Research
i. 4
weeks
c.
Preliminary Design
i. 4
weeks
d.
Detail Design
i. Timeline
2.
Ground testing: 6 weeks
a.
Specimen Test
i. 6
weeks
ii. Verification
of selected COTS components
iii. Subsystem
testing
iv. Flight
test site selection
3.
Flight testing: 32 weeks
a.
Prototype Build & Test
i. 8
weeks
ii. System
integration testing - ground
iii. Flight
testing
1.
Test preparation
2.
Flight test
iv. Begin
tracking MTBF
b.
Development & Modification
i. 8
weeks
ii. Continue
prototype iteration test flights
iii. Capture
MTBF data for production and sustainment
iv. Environmental
tests
c.
Certification
i. 16
weeks+
ii. Certification
deliverables
iii. Demonstration
of baseline requirements
4.
Production
a.
Initiate maintenance tracking system
5.
Sustainment
Justification
A fixed-wing system was selected for the task because it
provides greater range and endurance, and can therefore cover a greater area. The
faster images can be collected and analyzed, the greater the Probability of
Detection for a missing object or individual (US SAR Task Force, n.d.). Full-motion
video and recorded still images are desirable because the video can provide perspective
and context clues to the detailed image analysis, even if at a lower resolution
(Murphy, 2014, p. 128).
To reduce cost and development lead time, either a currently
available airframe with modifications or a new airframe built with COTS
sub-systems would be suitable. The development schedule reflects built-in time
for integration and verification of COTS component standards.
References:
Murphy, R.R. (2014). Disaster Robotics. Cambridge, MA: The MIT Press.
U.S. Search and Rescue Task Force. (n.d.). Search & rescue and disaster glossary
and acronyms. Retrieved from http://www.ussartf.org/glossary_acronyms.htm
