A spherical robot, also known as spherical mobile robot, or ball-shaped robot is a

mobile robot A mobile robot is an automatic machine that is capable of locomotion.Hu, J.; Bhowmick, P.; Lanzon, A.,Group Coordinated Control of Networked Mobile Robots with Applications to Object Transportation IEEE Transactions on Vehicular Technology, 202 ...

with spherical external shape. A spherical robot is typically made of a spherical shell serving as the body of the robot and an internal driving unit (IDU) that enables the robot to move. Spherical mobile robots typically move by rolling over surfaces. The rolling motion is commonly performed by changing the robot's center of mass (i.e., pendulum-driven system), but there exist some other driving mechanisms. In a wider sense, however, the term "spherical robot" may also be referred to a stationary robot with two rotary joints and one

prismatic joint A prismatic joint is a one- degree-of-freedom kinematic pair which constrains the motion of two bodies to sliding along a common axis, without rotation; for this reason it is often called a slider (as in the slider-crank linkage) or a sliding ...

which forms a spherical coordinate system (e.g., Stanford arm). The spherical shell is usually made of solid transparent material but it can also be made of opaque or flexible material for special applications or because of special drive mechanisms. The spherical shell can fully seal the robot from the outside environment. There exist reconfigurable spherical robots that can transform the spherical shell into other structures and perform other tasks aside from rolling. Spherical robots can operate as autonomous robots, or as remotely controlled (teleoperated) robots. In almost all the spherical robots, communication between the internal driving unit and the external control unit (data logging or

navigation system A navigation system is a computing system that aids in navigation. Navigation systems may be entirely on board the vehicle or vessel that the system is controlling (for example, on the ship's bridge) or located elsewhere, making use of radio or oth ...

) is wireless because of the mobility and closed nature of the spherical shell. The power source of these robots is mostly a battery located inside the robot but there exist some spherical robots that utilize

solar cells A solar cell, also known as a photovoltaic cell (PV cell), is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect.

. Spherical mobile robots can be categorized either by their application or by their drive mechanism.

Applications

Spherical mobile robots have applications in surveillance, environmental monitoring, patrol, underwater and planetary exploration, rehabilitation, child-development, and entertainment. Spherical robots can be used as amphibious robots viable on land as well as on (or under) water.

Locomotion

The most common drive mechanisms of the spherical robots operate by changing the robot's center of mass. Other driving mechanisms make use of: (1) conservation of angular velocity by flywheels, (2) environment's wind, (3) distorting the spherical shell, and (4) gyroscopic effect.

Current research

Th
research on spherical robots
involves studies on design and prototyping , dynamical modelling and simulation, control, motion planning, and navigation. From a theoretical point of view, the rolling motion of a spherical robot on a surface represents a

nonholonomic system A nonholonomic system in physics and mathematics is a physical system whose state depends on the path taken in order to achieve it. Such a system is described by a set of parameters subject to differential constraints and non-linear constraints, s ...

which has been particularly studied in the scope of control and motion planning.

Commercial spherical robots

Commercial spherical robots are available for sale to the public. Some current commercial products are GroundBot, Roball, and QueBall, as well as

Sphero Sphero, Inc. (formerly Orbotix) is an American consumer robotics and toy company based in Boulder, Colorado. Their first product, the Sphero, is a white spherical robot launched in December 2011 capable of rolling around under the control of a s ...

BB-8 BB-8 (or Beebee-Ate) is a Droid (Star Wars), droid character in the Star Wars, ''Star Wars'' franchise. He appeared in the three films of the Star Wars sequel trilogy, sequel trilogy, ''Star Wars: The Force Awakens'' (2015), ''Star Wars: The Las ...

, based on the droid character of the same name introduced in the 2015 film '' Star Wars: The Force Awakens''.

Samsung Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...

Ballie is a Spherical Rolling tennis Ball look alike personal robot which was introduced in Samsung CES2020. Sajid Sadi VP of the research team at Samsung is quoted saying that "Ballie’s ability to move around enables it to respond to a person wherever they are. Parents could ask Ballie to check up on kids to make sure they’ve completed their homework, for instance, or monitor the types of television shows and movies they’re watching."

External links

Spherical Robots: Research, Design, Application

References