mobile robot (mobile robotics)

Classifications and types of mobile robots

Mobile robots can be classified in two ways: by the environment in which they work and by the device they use to move.

Examples of different environment mobile robots include:

• Polar robots that are designed to traverse icy, uneven environments.
• Aerial robots, also known as unmanned aerial vehicles (UAVs) or drones, which fly through the air.
• Land or home robots, or unmanned ground vehicles (UGVs), that navigate on dry land or within houses.
• Underwater robots, or autonomous underwater vehicles (AUVs), that can direct themselves and travel through water.
• Delivery and transportation mobile robots that are designed to move materials and supplies around a work environment.

The different devices that can classify a mobile robot include:

• legs (human-like or animal-like legs)
• tracks
• wheels

There are also two main types of mobile robots: autonomous and non-autonomous, or guided, mobile robots.

Guided mobile robots require some form of instruction or guidance system in order to move, whereas autonomous mobile robots (AMRs) are able to move and explore their surroundings without any sort of external direction.

AMRs differ from autonomous guided vehicles (AGVs) because AMRs possess the ability to be more independent. AGVs typically require external guidance, such as magnet strips, wires or sensors installed in the environment's floor, thus creating an inflexible system that is both expensive and difficult to adjust as needs change. AMRs aim to overcome these obstacles by requiring little to no external guidance.

Features of a mobile robot

Each mobile robot will incorporate different features that optimize the system to meet a specific goal or perform a certain task. However, industrial mobile robot systems, perhaps the most commonly used today, possess several core features that should always be present. These features are:

• wireless communication
• integrated safety
• fleet simulation software
• Fleet management software
• integration with the company's supervisory software

Uses and functions of mobile robots

The basic functions of a mobile robot include the ability to move and explore, transport payloads, or revenue producing cargo, and complete complex tasks using an onboard system, like robotic arms. While the industrial use of mobile robots is popular, especially in warehouses and distribution centers, its functions can also be applied to the medicine, surgery, personal assistance and security. Ocean and space exploration and navigation are also amongst the most common uses of mobile robots.

Mobile robots are being used to access areas, such as nuclear power plants, where factors, like high radiation, make the area too dangerous for humans to inspect and monitor themselves. However, current mobile robotics is not designing robots that can tolerate high radiation without their electronic circuitry being impacted. Attempts to invent mobile robots to deal specifically with these situations are currently being made.

Other uses of mobile robots include:

• shoreline exploration of mines;
• repairing ships;
• a robotic pack dog or exoskeleton to carry heavy loads for military troopers;
• painting and stripping machines or other structures;
• robotic arms to assist doctors in surgery;
• manufacturing automated prosthetics that imitate the body's natural functions and
• patrolling and monitoring applications, such as surveilling thermal and other environmental conditions

Advantages and disadvantages of mobile robots

One major advantage of mobile robots is their computer vision capabilities. The complex array of sensors used by mobile robots to detect their surroundings allows them to accurately observe their environment in Real Time. This is valuable especially in industrial settings that are constantly changing and shifting.

The onboard intelligence system and AI used by AMRs creates another advantage. The autonomy provided by the mobile robots' ability to learn their surroundings through either an uploaded blueprint or by driving around and developing a map, enables the quick adaption to new environments and assists in the continued pursuit of industrial productivity.

Furthermore, mobile robots are flexible and quick to implement -- since they can create their own pathways and easily adapt -- possible to break up the implementation into different installations with a modular Deployment system and capable of removing the potential for human error by performing easily repeatable tasks, thus improving the safety of a facility or area.

Disadvantages of mobile robots include:

• limitations on the size of the load that can be carried;
• requiring large amounts of SKUs to operate at the highest level and
• continued challenges with wireless connections between the robot and information endpoint.

Safety and mobile robots

Since mobile robots, especially AMRs, are loaded with cameras and sensors, they are able to understand their environment at a higher level, thus, as mentioned before, eliminating the risk of human negligence and the accidents and other safety risks that could occur as a result of human error.

However, since the field of mobile robotics is rapidly expanding, it is necessary to create safety standards and guides specifically for mobile robots. Currently, the only relevant safety standards come from a combination of the American National Standards Institute (ANSI), the Industrial Truck Standards Development Foundation (ITSDF) and the Robotic Industries Association (RIF). The guides are the ANSI/ITSDF B56.5-2012 Safety Standard for Driverless, Automatic Guided Industrial Vehicles and Automated Functions of Manned Industrial Vehicles and the ANSI/RIA R15.06-2012 Industrial Robots and Robot Systems – Safety Requirements.

Although both guides are important, they fail to cover some of the latest technology. Safety standards that cover all areas of mobile robotics must be made and monitored to ensure the wellbeing of human workers, especially as advancements are made and new features are added to mobile robot systems.

The RIA and ANSI are currently working together with other key industry representatives to develop a guide of safety standards specifically for industrial mobile robots, called R15.08. The standards will be published in three parts:

1. Part one will define the safety requirements for manufacturers of industrial mobile robots.
2. Part two will outline the different requirements for companies who are looking to create, install and integrate a secure mobile robot system.
3. Part three will specify the safety requirements for end users of industrial mobile robots.

Emergence, history and the future of mobile robots

Elmer and Elsie, the world's first electronic autonomous mobile robots were created in 1948 by Dr. William Grey Walter in Bristol, UK. In 1961, UNIMATE, the first industrial robot, was introduced at the General Motors factory is New Jersey. Since these events, work and research has been continuously conducted to improve and advance the mobile robot.

In 1968, Marvin Minsky invented the octopus-like Tentacle Arm. One year later, in 1969, the Stanford Arm was created. The Stanford Arm was the first computer-controlled, electrically powered robot arm.

In 1970, SRI International introduced Shakey, the first mobile robot controlled by AI.

In 1974, the Silver Arm was invented. This was a robotic arm that could perform small-parts assembly by gathering feedback from touch and pressure sensors.

In 1979, the Stanford Cart crossed a room, without human assistance, using a TV camera that took pictures from multiple angles and sent them back to a computer. The computer would then analyze the distance between the robot and the objects and direct the Stanford Cart where to go.

Since the early 2000s, experiments have been performed to investigate the use of neural networks to control AI in mobile robots.

Looking into the future, manufacturers are trying to find more applications for mobile robots outside the industrial environment. The current technology is a blend of hardware, software and advanced machine learning; it is considered to be solution-focused and evolving fast. AMRs continue to struggle with travelling from one point to another; the improvement of spatial recognition is necessary. The Simultaneous Localization and Mapping (SLAM) algorithm design is one innovation that is attempting to resolve this issue.

Mobile robots could end up being crucial to both agriculture and construction, two markets that are suffering from labor shortages. Both sectors require large amounts of dirty, boring, dangerous work that could be better executed by mobile robots.  

The use of mobile robots in homes is also a future possibility, but the improved reliability of large mobile robot systems is required as well as an elimination of the barrier between the robot and human worlds.