In October 2024, French company Dassault Systeme announced that it will soon launch unmanned wingmen for the Rafale fighter jet to assist it in carrying out strike missions in the future. It is reported that the unmanned wingman is powered by a turbofan engine to provide it with long-term endurance and excellent high-altitude performance. For unmanned equipment, the importance of power equipment is self-evident. Power equipment is like the "heart" of unmanned equipment, mainly responsible for power generation, transmission, and supply of combat energy in unmanned equipment. The suitability of its selection is closely related to the success or failure of unmanned equipment development work. From "single energy dominance" to "multi-source collaboration", from the mechanical age to the intelligent age, the continuous progress of energy and power technology is supporting unmanned equipment from the laboratory to the battlefield, from concept verification to large-scale application, and is having an undeniable impact on the battlefield rules in the unmanned field. Today, let's take a closer look at the evolution history of unmanned equipment power technology, and understand its leapfrog development process from singularity to diversification, from high energy consumption to high efficiency, from relying on fossil fuels to embracing clean energy. In the early stages of the development of unmanned equipment, thermal power devices stood out. In the second half of the 20th century, countries around the world began to explore unmanned platforms such as drones and unmanned surface vessels. Various types of unmanned equipment began to play an important role in remote strikes, reconnaissance and detection, and the research and development of unmanned equipment was in an emerging stage. During this period, with mature technological systems and stable output power, thermal power devices such as internal combustion engines became the absolute mainstay of emerging unmanned equipment power sources. At that time, the commonly used thermal power devices for unmanned equipment mainly included piston engines, turbine engines, and rocket engines. Among these three commonly used thermal power devices, piston engines are the most common. In a sealed container, fuels such as gasoline and kerosene are mixed with air and undergo combustion, expansion, and work to ultimately generate power. This type of engine has the advantages of low fuel consumption, low failure rate, and light weight, and is a commonly used power source solution in the early development of unmanned equipment. It is widely used in the manufacturing of ground unmanned vehicles, unmanned surface boats, and small and medium-sized unmanned aerial vehicles. The well-known "Predator" drone of the US military is a typical representative of using such engines. Equipped with the Rotax 914 turbocharged gasoline piston engine, the Predator can operate safely and stably even in desert and plateau environments with complex weather conditions. Another type of turbine engine, commonly used as a power source for unmanned helicopters, mainly includes turbojet, turbofan, turboprop, and turboshaft engines. This type of engine can improve the payload capacity, cruising speed, and hovering time of unmanned aerial vehicles, such as the single engine turboshaft engine used by the US MQ-8B fire reconnaissance unit. Rocket engines are mainly used for high-speed and ultra high speed unmanned aerial vehicles. This type of unmanned equipment comes with its own propellant, which is converted into kinetic energy within the rocket engine, forming a high-speed jet to generate thrust. For example, the supersonic AQM-37 series unmanned target aircraft developed by the United States is mainly used for simulating air-to-air targets, air to ground ammunition, and ballistic missiles in military exercises. It is powered by rocket engines and can fly at speeds of 3-4 Mach with a range of over 180 kilometers. It can simulate high-speed flying targets and meet the needs of military training and weapon testing. At the same time, the drawbacks of thermal power devices cannot be ignored. Taking piston engines as an example, rigid connection devices such as gear transmission are usually used between the prime mover and the driving wheels, resulting in poor flexibility in the structural design of piston engines. Moreover, the engine must be continuously started during operation, with high noise, obvious infrared characteristics, and poor concealment. Most thermal power devices still suffer from the common problem of low thermal efficiency. A large amount of energy is lost in the form of waste heat, and these obvious thermal signals are easily locked by enemy sonar or infrared detection equipment, limiting their operational concealment. For example, the US AQM-34 unmanned reconnaissance aircraft, which mainly performs various tasks such as reconnaissance, surveillance, and electronic warfare, has been heavily deployed in the Vietnam battlefield. But the infrared characteristics of the unmanned equipment power system are obvious, making it easy to be detected and shot down by infrared guided missiles on the battlefield. Overall, thermal power devices laid the foundation for the early development of unmanned equipment, but their high energy consumption and low concealment also forced researchers to constantly seek cleaner and more efficient alternative solutions. With the advancement of battery technology, unmanned equipment has ushered in explosive development. At the beginning of the 21st century, breakthroughs in battery technology greatly accelerated the development process of unmanned equipment, and the power source of unmanned equipment has a new option of electric drive. With its low noise and zero emissions characteristics, electric propulsion enables unmanned equipment to demonstrate unique advantages in reconnaissance, surveillance, and other tasks. However, the endurance of unmanned equipment is limited by the energy density and power density of the battery. Due to the limited energy stored in batteries and the difficulty in supplying energy to unmanned equipment in outdoor combat environments, electric propulsion is currently mainly used in light, small, and micro unmanned equipment. Among these unmanned equipment, the most commonly seen are rechargeable batteries such as nickel hydrogen batteries, lithium-ion batteries, and lithium polymer batteries. These types of batteries are often able to output considerable power and are favored by users. Taking lithium polymer batteries as an example, this battery uses polymer electrolytes instead of traditional porous separators immersed in electrolytes. This solid-state polymer design allows users to freely choose the shape of the battery to meet the special needs of different application fields. The "Rod" wheeled robot from Spain was one of the earliest unmanned equipment to adopt electric propulsion. It is reported that the battery powering the robot can provide continuous power for 2 hours, and the robot can reach a maximum speed of 6.5 kilometers per hour. The REMUS-100 unmanned underwater vehicle, which was used to search and clear mines for the US Navy during the Iraq War, also uses electric propulsion as its power source. If the unmanned underwater vehicle travels at a speed of 3 kilometers per hour, the lithium battery carried in the vehicle can ensure continuous navigation for 9 hours. In addition, within the field of electric propulsion, there is a special energy device - fuel cell - that deserves people's attention. Although the name of a fuel cell contains the word 'battery', its operating principle is very different from that of a conventional battery. When conventional batteries store electrical energy, they generally generate heat energy through fuel combustion, which is then converted into mechanical energy by mechanical devices. This energy is then used to drive a generator to generate electric potential and current, which are then stored in the battery. Fuel cells do not require intermediate steps and can directly convert chemical energy stored in oxidants and fuels into electrical energy through electrode reactions. They have the advantages of high energy conversion efficiency, low environmental pollution, and low noise. Several countries have made significant attempts around fuel cells. On the basis of the Hermes series unmanned reconnaissance aircraft, Israel is exploring the development of high-altitude long endurance unmanned aerial vehicles powered by fuel cells; The American seahorse unmanned underwater vehicle, which uses fuel cells, has a maximum speed of 6 knots and can operate continuously for nearly 100 hours within a radius of 90 kilometers, meeting the requirements for long-term remote intelligence collection, surveillance, and reconnaissance tasks... However, due to technological limitations, the cost of fuel cells is still relatively high and their size is large, making them unsuitable for the application design of small unmanned equipment. Electric drive has greatly expanded the application scenarios of unmanned equipment. The American "hover light" drone is connected to ground power through a cable, and although its maneuvering range is limited to the length of the cable, it achieves 72 hours of aerial monitoring. The UK's "Cormorant" solar assisted electric drone is being used for biodiversity survey missions. In the Amazon rainforest, electric powered drones effectively avoid the pollution caused by fuel to the environment. Compared with thermal power systems, electric drive has unique advantages, but we still need to recognize its limitations in terms of endurance and environmental adaptability, which has led to the emergence of third-generation hybrid technology. Hybrid power+intelligent energy regeneration "leads a new direction of development. With the promotion and application of unmanned equipment in fields such as intelligence reconnaissance, environmental surveying, and cross domain rescue, some complex tasks have put forward higher requirements for its endurance, environmental adaptability, and concealment. The traditional single energy power mode is gradually becoming unsustainable. In this context, the advancement of hybrid power and energy intelligent regeneration technology has broken the dependence of unmanned equipment on a single energy source, and the energy power system of unmanned equipment has begun to shift from "single energy dominance" to "multi-source collaboration". Hybrid power is not a new concept. As early as the era of thermal power, there was a precedent for conventional ships to mix internal combustion engines and diesel engines. After the mature development of electric drive technology, more and more unmanned equipment has turned their attention to oil electric hybrid power in their design. This multi energy collaborative mechanism can not only significantly improve the overall efficiency of the power system, but also achieve real-time optimization configuration of different energy sources through intelligent energy management algorithms, extending the endurance time of unmanned equipment to several times that of traditional systems. For example, the American MQ-25 "Stingray" unmanned refueling aircraft is powered by a turbofan engine and battery pack. It is powered by fuel during high-speed cruising and switches to electric mode during covert penetration, reducing noise by about 70%. For example, the Ukrainian Magura V5 unmanned surface craft also uses a hybrid electric vehicle, with a cruising speed of up to 22 knots and a sprint speed of up to 42 knots. Before approaching the target, it uses a noisy engine to drive, and after approaching the target, it switches to battery drive to achieve silent navigation. Compared to hybrid design of mature technologies such as thermal and electric power, integrating emerging energy technologies such as wind, solar, and wave energy into existing power systems is more experimental and exploratory. For example, the British C-Enduro unmanned surface vessel is equipped with a 720 watt wind turbine and 12 solar panels in addition to traditional diesel generators. Driven by dual DC motors, it can reach a maximum speed of 7 knots and can sustain autonomous navigation for 3 months, demonstrating good comprehensive dynamic performance. In terms of development direction, continuous breakthroughs in energy regeneration technology are also restructuring the energy supply system - using piezoelectric materials, biomimetic flapping wing aircraft convert mechanical vibrations into electrical energy; Underwater submersibles use ocean current temperature difference power generation devices to achieve self-sustaining power supply; Ground unmanned vehicles are equipped with foldable solar films for autonomous energy storage during parking... What is even more revolutionary is the breakthrough in wireless charging matrix and aerial energy relay technology, which enables drone groups to complete "aerial refueling" through electromagnetic resonance or laser energy transmission during missions, building a three-dimensional energy supply network. For example, the Korean Academy of Science and Technology has developed a 20m laser wireless charging system, which can provide real-time energy replenishment for 5kg level drones and greatly improve transmission efficiency. Diversified integration is not only reflected in the technical aspect, but will also give rise to a new concept of equipment application - the combination of flexible batteries with biodegradable properties and hydrogen fuel cells, thereby achieving zero pollution self destruction of disposable reconnaissance equipment; After the combination of miniature nuclear batteries and supercapacitors, deep space probes will receive continuous power supply for decades; The maturity of energy information integration technology has made the power system itself a data relay node, synchronously completing information exchange when transmitting electrical energy... Any breakthrough in the application of these fields in the future will lead to another leap in the development of unmanned equipment. From the roar of internal combustion engines