# Mobile Robot

## Summary


Mobile robots can move autonomously that is without any assistance from external human operators. A robot is called autonomous when it can determine the actions to be taken to perform a task, using a perception system that helps it. It also needs a control system to coordinate all the subsystems that compromise the robot. 

Mobile robots function using a combination of **artificial intelligence (AI)** and physical robotic elements like wheels, tracks and legs. Mobile robots are popular in different sectors. They are used to assist with work processes and even accomplish tasks that are impossible or dangerous for humans. Humanoid robots, entertainment pets, drones, and underwater robots are great examples of mobile robots. They are different from other robots because of their ability to move autonomously. These robots have the intelligence to decide based on algorithms it takes input and gives the expected output.

## Discussion

### What are the features of a mobile robot?

Every mobile robot will incorporate different features that optimize the system to meet a specific goal or to perform a particular task. However, industrial mobile robot systems are mostly used today. They possess several core features that should always be present. These features are: 

    + Integrated safety: Safety is the main thing that a mobile robot is
    + Wireless communication
    + Fleet management software
    + FLeet simulation software
    + Integration with supervisory software

### What are the different types of mobile robots?

Mobile robots are classified in two ways based on the environment they work in and on the device they use to work. 

 

    + *Aerial robots*: These are also known as Unmanned Aerial Vehicles (UAVs). They can fly through the air. Eg: drones, helicopters, etc.
    + *Land robots*: They are also known as Unmanned Ground Vehicles (UGVs). These robots can navigate on dry land and in buildings. They are used to supply equipment. Eg: Dirtdog etc.
    + *Underwater Robots*: Autonomous Underwater Vehicles (AUVs) are the other name for underwater robots. They can direct themselves and efficiently travel through water. Eg: Wave gliders.
    + *Wheeled robots*: Wheeled robots are known as Autonomous Intelligent Vehicles (AIVs). These use the wheels for their locomotion. There are different types of wheeled robots like one-wheeled robots, two-wheeled robots, etc.
    + *Humanoid robots*: They have the shape of a human body. They work majorly with the help of sensors. Eg: Androids, etc.
    + *Legged robots*: These robots use articulated limbs like legs and follow a mechanism to provide locomotion. Eg: Haxapad robot etc.

### What are the parts of a mobile robot?

The main components of an autonomous mobile robot are a microcontroller, chassis, motors, and sensors. 

 

    + **Microcontroller / SBC**:A microcontroller is the brain of the robot. Arduino and Raspberry Pi are popular options. Raspberry Pi is a single-board computer (SBC) that can run a full Linux OS. An Arduino is ideal for simple robotics projects. Some microcontrollers are Teensy, BeagleBone, micro: bit, and Raspberry Pi Pico.

    + **Chassis**:The chassis is the body where electronics and motors are mounted. They come in various sizes and materials. Some alternative chassis is made with plastic, metal, wood, or cardboard.

    + **Motors**:Motors are fuel for a robot. Some motors have an inbuilt gearbox to increase torque and drive heavier loads. PWM (pulse-width modulation) controls motor speed.

    + **Power**:The power source is of two types. Use separate power sources for motors and electronics. Another is using a single power source connected to both via a BEC (battery eliminator circuit). USB power banks, battery packs, and LiPo batteries are examples.

    + **Sensors**:Sensors allow the robot to move autonomously. An ultrasonic distance sensor sense an obstruction. An IR sensor detects a dark line. 


### What are the types of sensors used in mobile robots?

Sensors are the eyes of a mobile robot. When combined with sensor software algorithms, sensors allow a robot to understand and navigate the environment, detect and avoid collision with objects, and provide location information about the robot. Exteroceptive sensors visualize the world with cameras, lasers, lidar, radar, sonar, infrared, touch sensors such as whiskers or bump sensors, GPS and proximity sensors.

Proprioceptive sensors deal with the robot itself. They include accelerometers, gyroscopes, magnetometers, compass, wheel encoders and temperature sensors.

Some typical sensors used in ground mobile robots and drones include:

Inertial measurement units (IMUs) combine multiple accelerometers and gyroscopes. They also include magnetometers and barometers. GPS provides latitude, longitude and altitude information. Vision sensors like cameras, both 2D and 3D, as well as depth cameras play an important role in mobile robots. Computer vision and deep learning can aid object detection and avoidance, obstacle recognition and obstacle tracking. Visual odometry and visual-SLAM are becoming more relevant for mobile robots operating in both indoor and outdoor environments. 


### What is the control system used in a mobile robot?

A robot control system manages commands and directs or regulates the movement and function of various parts of the mobile robot to achieve the desired result. Automatic control is an important requirement for any robotics control installation. The control system of a robot is a feedback control system. It continuously reads from sensors and updates the commands for the actuators to achieve the desired robot behavior. The controller controls and coordinates all aspects of the operation. For high-level performance, the robotics control uses a closed-loop control system like PID controllers, which uses sensor feedback. A feedback control system consists of five basic components like: 

    + Input
    + Process being controlled
    + Output
    + Sensing elements
    + Controller and actuating devices

### what does it make a mobile robot autonomous?

Autonomous mobile robots act on their own. It is programmed to respond the outside stimuli. These robots have a bumper sensor to detect obstacles. When a robot hits an obstacle, the impact triggers the bumper sensor. The robot's programming tells it to back up and take another direction. Mobile robots often use infrared or ultrasound sensors to see obstacles. More advanced robots analyze and adapt to unfamiliar environments like rough terrain. These robots may associate certain terrain patterns with certain actions. The best example of an advanced robot is NASA's preservance rover. 


### Which areas and sectors can collaboratively mobile robots be applied to?

The basic function of a mobile robot is to move and explore, transport, and complete complex tasks. They are also used in medicine, surgery, personal assistance, and security. 

Some uses of mobile robots in many areas and sectors such as:

    + **Health Care**:Robotics has the potential to change many health care practices like surgery, rehabilitation, and therapy. Robotics are used in surgeries like cardiac, gynecologic, thoracic, urologic, etc. 

    + **Agriculture**:There is a rise in the experimental use of mobile robots in operations like pruning, thinning, mowing, spraying, and weed removal. 

    + **Food and Beverage Industry**:Mobile robots are used on stationary conveyor equipment. These robots do offer a high amount of operational flexibility. 

    + **Manufacturing**:Robotics is being used in many aspects of manufacturing to increase productivity and efficiency while lowering production costs. Robotic manufacturing technology became safe to operate. 

    + **Military**:Robotic technology is being applied in many areas of the military. An unmanned drone is an example. Military drones flying over areas of war and conflict, in hostage situations, and during natural and manmade disasters can assess danger levels and provide soldiers and first responders with real-time information. 

## Milestones

1942

Do you know that robots are used in World War II? Yes, this is the first time that robots are used in real-time war situations. These mobile robots are used as flying bombs to deploy bombs on enemies .


1960

In the present era, we all know that robots can charge themselves when they ran out of power. But this technology was first implemented by Johns Hopkins University. The name of the robot that used this technology is "Beast". One more interesting fact is it uses sound waves to move around .


1976

Till 1976 robots are used in land and water applications. For the first time, NASA used a mobile robot in a space mission to Mars. The name of the program is Viking program .


1989

Mark Tilden used simple analog circuits like comparators instead of microprocessors. He proved that robots can be in the simplest shapes and efficient in doing a task .


1996

After the Viking program, NASA used mobile robots again in its Mars Pathfinder mission. They used the robot in their rover Sojourner to explore the surface of Mars .


1999

Sony designed a robot similar to a dog called Aibo. It is the first robotic dog designed by Sony. It is capable of seeing, walking and interacting with its environment .


2002

Robots are used in wars, on land and water applications, and in space too. Then iRobot organization invented a mobile robot for domestic applications. The name of the robot is Roomba .


2005

Boston Dynamics invented a quadruped robot that can carry heavy loads in terrain areas too .


2016

Mobile robots are used in solving crimes too. US police used a mobile robot named MARCbot. The Multi-Function Agile Remote-Controlled Robot (MARCbot) helped the US police to kill a sniper who killed 5 police officers in Dallas, Texas which raises ethical questions regarding the use of drones and robots by police as instruments of lethal force against a perpetrator.