History has proven that advancements in materials science and engineering have been essential drivers in the growth of sensor technologies. For example, the temperature sensitivity of electrical resistance in a range of materials was first observed in the early 1800s and was implied by Wilhelm von Siemens in 1860 to build a temperature sensor based on a copper resistor. The high resonance stability of single-crystal quartz, in addition to its piezoelectric functions, has made possible an extraordinarily wide fleet of high performance and cheap sensors that have played an instrumental role in national defense sector as well as everyday life.
In simple words, a sensor is a device, module, or machine whose work is to detect changes in its environment and send signals to the other electronics system (computer system). A sensor is orphan without other electronic devices.
Sensors in Defense
Modern military and defense environments require proven, scalable, and reliable technologies. Sensors are a vital part of the technologies as these provide a solution to the entire military and defense ecosystem. Military and defense systems include spacecraft, missiles, military vehicles, ships, drones, marine systems, rockets, and satellites. These systems work in the most jarring environments during usual as well as combat operations. Internal and external security systems depend on intelligent sensor technology for surveillance, reconnaissance, and combat operations.
Sensors are found in various security systems, chemical warfare, explosive detection systems, crime detection systems, and civil establishments, among others. Modern warfare sensors are deployed on Land, aerial platforms, in space and underwater to keep 24×7 watch over a target zone.
Sensors and Command and Control
The missile defense system is equivalent to nothing without sensors and command and control systems. These systems help locate the threat and kill it. While interceptors capture images, sensors are the underappreciated part of missile defense operations. Sensors play a critical role throughout the process: early warning, tracking, fore control, discrimination, and kill the target.
Missile defense system depends on sensor signals from a wide range of ground and sea-based radars in addition to overhead satellites — these separate sensors provide information on the target to the GMD File Control (CFC). GFC is supported by Command, Control, Battle Management, and Communications (C2BMC) software. It integrates and transmits the information to GBIs In-Flight via In-Flight Interceptor Communications System (IFICS) Data Terminals (IDTs).
Advancements in sensors technology can result in more lethality, magazine capacity, and contribute to a robust defense.
Sensors Application in Defense
- Intelligence and Reconnaissance
- Communications and Navigation
- Combat Operations
- Electronic Warfare
- Target Recognition
- Command and Control
- Surveillance and Monitoring
Defense Platforms using Sensors
- Fighter Aircraft – F-15 Eagle, Saab JA S 39 Gripen
- Helicopter – Mi MI 26, Mi Mi 24, Bell UH-1N Twin Huey
- Combat Support Aircraft – Aero L-29 Albatros, L-39 MS
- Unmanned Aerial Vehicles (UAVs) – MQ-1 Predator, RQ-4 Global Hawk
- Armed Ground Vehicles – BAE Caiman, RG-33
- Combat Support Vehicles – M1 Assault Breacher, M60A1 AVLB
- Unmanned Ground Vehicles – Gladiator Tactical, BTR-90
- Operating Bases
- Combat Ships – USS Independence (LCS-2), USS Freedom (LCS-1)
- Combat Support Ships – (AOE-1) USS Sacramento, (AOE-3) USS Seattle
- Submarines – Type VII Submarine, Yasen Class Submarine
- Unmanned Marine Vehicles – Spartan Owl, LDUUV
- Rockets and Missiles – AIM-9 Sidewinder, AIM-7 Sparrow
- Guided Ammunition – BOLT-117, F-111F
- Torpedoes – Yu-9, Sting Ray, Mark 50
- Artillery Systems – 2S35 Koalitsiya-SV, PzH 2000
Aviation and Aerospace Sensors
Electronic sensors enable accurate feedback and ease of control of aircraft systems. Sensors help scale various parameters like monitoring, control, and navigation. Hence, electronic systems play a vital role in modern aviation.
Avionic or electronic systems include devices for communication, display, navigation, searchlights and complicated tactical systems for airborne early warning signals. All sensors installed in aircraft are for flight instruments – these sensors include tachometers, engine temperature gauges, fuel, and oil quantity gauges, airspeed measurement meters, and others. There are several sensors for ground testing, lightening-detection radars, terrain radars, and stall warning systems. Many of these control sensors send signals to pilots to take proper actions and precaution and prevent any kind of disaster or accident. The pilot receives signals through the cockpit. Hence, he continuously supervises the status of the engine and environment from the cockpits.
Types of sensors in Aviation
a) Flow Sensors – These sensors are used to supervise the volume of oil and liquid coolant fluid in fuel transfer and bleed air systems. Esterline Corp. and Crane Aerospace & Electronics are among companies that manufacture flow sensors.
b) Pressure Sensors –
These sensors supervise the pressure in hydraulic systems, raising, braking and lowering landing gear oxygen tanks, and coolant fluids.
c) Temperature sensors – These sensors are used to monitor the conditions of fuels, refrigerants, and environmental cooling systems. These sensors embody thermometers, Whitestone bridge indicators, ratiometers, and thermocouples. Omega Engineering Inc. is a leading manufacturer of temperature sensors.
d) Position sensors –
Linear Variable differential transformers (LVDTs) and rotary variable differential transformers (RVDTs) are used to monitor the displacement of aircraft components. Manufacturers such as BEI Sensors and Active Sensors are leading the position sensors market.
e) Force and vibration sensors – These sensors measure torque and force in breaking and actuation systems as well as in-flight controls.
f) Gyroscopes – Gyroscopes are used for navigation as well as controlling the turning and attitude aircraft. Microelectronic mechanical sensors (MEMS) gyroscopes are used in modern jets. Watson Industries is making gyroscopes for the aviation industry.
g) Attitude heading and reference systems –
Today Attitude heading and reference systems (AHRSes) have replaced most gyroscopes in modern aircraft. AHRSes are used to receive data from MEMS devices, GPS, magnometers, and accelerometers.
Key Market Players
The major players in the military sensors market:
- Honeywell International Inc. (US)
- TE Connectivity Ltd. (US)
- Thales Group (France)
- Curtiss-Wright Corporation (US)
- Raytheon Company (US)
- Esterline Technologies Corporation (US)
- Kongsberg Gruppen ASA (Norway)
- BAE Systems plc (UK)
These players have followed multiple growth stratagems as contracts, acquisitions, expansions, new product launches, and partnerships & agreements to expand their presence in the defense sensors industry.
Analysts say that the defense sensors market is forecasted to grow at a compound annual growth rate (CAGR) of 5.1%, boosting the market form $24.7 Billion in 2019 to $33.2 Billion by 2025. Factors that are expected to drive the growth include increase in procurement of defense systems by countries’ military forces and continual military improvisation programs.
Although the North American region is expected to lead the defense sensors market, the Asia pacific region is predicted to rise at the highest CAGR from today to 2025. China and India are the two main emerging countries driving the growth.
1) What is the difference between gyroscopes and AHRS?
An attitude and heading reference system (AHRS) consists of sensors on three axes that provide attitude information for aircraft, including roll, pitch and yaw – these are also called MARG sensors and consists of MEMS. They are developed to replace traditional gyroscopes.
2) How does AHRS Work?
An AHRS uses tiny sensors to measure acceleration, and a fast computer chip analyzes those forces and calculates airplane attitude.