Unmanned ground vehicles (UGVs) are robotic systems that operate on land without an onboard human operator. They are used for a wide variety of both civilian and military applications, particularly in environments that are hazardous or unpleasant to humans and for tasks that are difficult, dull or pose unacceptable risks.
UGV platforms may be designed from scratch or based on an existing manned land vehicle such as a Land Rover. Vehicle kits are also available for converting manned vehicles into UGVs, and may provide optionally manned capabilities that allow users to select crewed or uncrewed operation.
UGVs may be remotely controlled via a handheld or fixed control station, or operate autonomously. Autonomous UGVs can travel between pre-defined waypoints, or roam throughout the environment to execute their mission. UGVs operating in previously uncharted or constantly changing environments may have to collect information and build up a map of their surroundings using techniques such as simultaneous localization and mapping (SLAM). Artificial intelligence and machine learning may also help them adapt to their surroundings.
The three main UGV locomotion methods are wheels, tracks and legs. Wheels are power-efficient and allow the highest speeds on flat ground, but are not good for traversing off-road and uneven terrain, as they can get stuck or sink into the ground due to low contact surface area and thus higher pressure. Tracks are the best option for rugged terrain, but are slower, less efficient, involve more mechanical complexity and cause more vibration. Legged ground robots can cope with a wide variety of terrain, but are limited in speed and require complex control and stability hardware.
Small UGVs can be powered by electric batteries. Larger ones may use a petrol or diesel engine, or a hybrid system that uses a combustion engine to drive an electric generator rather than directly connecting to the locomotion system. Hydrogen fuel cell power systems for UGVs are also under development.
Wireless communications are required to operate UGVs remotely, as well as to relay video footage and other sensor data. This will typically be done by RF (radio frequency) communications, satellite links, or wireless fiber optic. UGVs will often require non-line of sight (NLOS) communications due to operating in urban and cluttered environments. Mobile ad hoc network (MANET) technology is often utilised in order to help UGVs maintain links even in adverse conditions.
UGVs can be equipped with a variety of sensors and payloads. Due to operating in indoor and other GNSS-denied environments, UGVs may rely on LiDAR sensors, combined with inertial navigation systems and vehicle odometry, for accurate navigation. Mission-specific sensors and payloads include RGB and thermal cameras, manipulator arms, chemical and explosives sensors, and weapons systems.
UGVs are used for a wide range of civilian applications such as urban search and rescue, firefighting, nuclear plant operations, crowd control and agricultural spraying and harvesting.
Military UGV uses include EOD (explosive ordnance disposal), equipment carrying, forward reconnaissance, mobile weapons platforms and manned-unmanned teaming. Many UGV platforms can be quickly reconfigured to perform multiple roles.