Gyroscope in the context of "Devil sticks"

Mechanics (from Ancient Greek μηχανική (mēkhanikḗ) 'of machines') is the area of physics concerned with the relationships between force, matter, and motion among physical objects. Forces applied to objects may result in displacements, which are changes of an object's position relative to its environment.

Theoretical expositions of this branch of physics have their origins in Ancient Greece, for instance, in the writings of Aristotle and Archimedes (see History of classical mechanics and Timeline of classical mechanics). During the early modern period, scientists such as Galileo Galilei, Johannes Kepler, Christiaan Huygens, and Isaac Newton laid the foundation for what is now known as classical mechanics.

A smartphone is a mobile device that combines the functionality of a traditional mobile phone with advanced computing capabilities. It typically has a touchscreen interface, allowing users to access a wide range of applications and services, such as web browsing, email, and social media, as well as multimedia playback and streaming. Smartphones have built-in cameras, GPS navigation, and support for various communication methods, including voice calls, text messaging, and internet-based messaging apps. Smartphones are distinguished from older-design feature phones by their more advanced hardware capabilities and extensive mobile operating systems, access to the internet, business applications, mobile payments, and multimedia functionality, including music, video, gaming, radio, and television.

Smartphones typically feature metal–oxide–semiconductor (MOS) integrated circuit (IC) chips, various sensors, and support for multiple wireless communication protocols. Examples of smartphone sensors include accelerometers, barometers, gyroscopes, and magnetometers; they can be used by both pre-installed and third-party software to enhance functionality. Wireless communication standards supported by smartphones include Wi-Fi, Bluetooth, Hotspots and satellite navigation. By the mid-2020s, manufacturers began integrating satellite messaging and emergency services, expanding their utility in remote areas without reliable cellular coverage. Smartphones have largely replaced personal digital assistant (PDA) devices, handheld/palm-sized PCs, portable media players (PMP), point-and-shoot cameras, camcorders, and, to a lesser extent, handheld video game consoles, e-reader devices, pocket calculators, and GPS tracking units.

A virtual reality headset (VR headset) is a head-mounted device that uses 3D near-eye displays and positional tracking to provide a virtual reality environment for the user. VR headsets are widely used with VR video games, but they are also used in other applications, including simulators and trainers. VR headsets typically include a stereoscopic display (providing separate images for each eye), stereo sound, and sensors like accelerometers and gyroscopes for tracking the pose of the user's head to match the orientation of the virtual camera with the user's eye positions in the real world. Mixed reality (MR) headsets are VR headsets that enable the user to see and interact with the outside world. Examples of MR headsets include the Apple Vision Pro and Meta Quest 3.

VR headsets typically use at least one MEMS IMU for three degrees of freedom (3DOF) motion tracking, and optionally more tracking technology for six degrees of freedom (6DOF) motion tracking. 6DOF devices typically use a sensor fusion algorithm to merge the data from the IMU and any other tracking sources, typically either one or more external sensors, or "inside-out" tracking using outward facing cameras embedded in the headset. The sensor fusion algorithms that are used are often variants of a Kalman filter. VR headsets can support motion controllers, which similarly combine inputs from accelerometers and gyroscopes with the headset's motion tracking system.

In computing, a motion controller is a type of input device that uses accelerometers, gyroscopes, cameras, or other sensors to track motion.

Motion controllers see use as game controllers, for virtual reality and other simulation purposes, and as pointing devices for smart TVs and Personal computers.

A smartphone is a mobile device that combines the functionality of a traditional mobile phone with advanced computing capabilities. It typically has a touchscreen interface, allowing users to access a wide range of applications and services, such as web browsing, email, and social media, as well as multimedia playback and streaming. Smartphones have built-in cameras, GPS navigation, and support for various communication methods, including voice calls, text messaging, and internet-based messaging apps. Smartphones are distinguished from older-design feature phones by their more advanced hardware capabilities and extensive mobile operating systems, access to the internet, business applications, mobile payments, and multimedia functionality, including music, video, gaming, radio, and television.

Smartphones typically feature metal–oxide–semiconductor (MOS) integrated circuit (IC) chips, various sensors, and support for multiple wireless communication protocols. Examples of smartphone sensors include accelerometers, barometers, gyroscopes, and magnetometers; they can be used by both pre-installed and third-party software to enhance functionality. Wireless communication standards supported by smartphones include LTE, 5G NR, Wi-Fi, Bluetooth, and satellite navigation. By the mid-2020s, manufacturers began integrating satellite messaging and emergency services, expanding their utility in remote areas without reliable cellular coverage. Smartphones have largely replaced personal digital assistant (PDA) devices, handheld/palm-sized PCs, portable media players (PMP), point-and-shoot cameras, camcorders, and, to a lesser extent, handheld video game consoles, e-reader devices, pocket calculators, and GPS tracking units.

Axial parallelism (also called gyroscopic stiffness, inertia or rigidity, or "rigidity in space") is the characteristic of a rotating body in which the direction of the axis of rotation remains fixed as the object moves through space. In astronomy, this characteristic is found in astronomical bodies in orbit. It is the same effect that causes a gyroscope's axis of rotation to remain constant as Earth rotates, allowing the devices to measure Earth's rotation.

Jean Bernard Léon Foucault (UK: /ʒɒ̃ ˈbɛərnɑːr ˌleɪɒ̃ ˈfuːkoʊ/, US: /ˌʒɒ̃ bɛərˈnɑːr leɪˌɒ̃ fuːˈkoʊ/; French: [ʒɑ̃ bɛʁnaʁ leɔ̃ fuko]; 18 September 1819 – 11 February 1868) was a French physicist who invented the Foucault pendulum, a device demonstrating the effect of Earth's rotation. He also made an early measurement of the speed of light, discovered eddy currents, and is credited with naming the gyroscope.

Precession is a change in the orientation of the rotational axis of a rotating body. In an appropriate reference frame it can be defined as a change in the first Euler angle, whereas the third Euler angle defines the rotation itself. In other words, if the axis of rotation of a body is itself rotating about a second axis, that body is said to be precessing about the second axis. A motion in which the second Euler angle changes is called nutation. In physics, there are two types of precession: torque-free and torque-induced.

In astronomy, precession refers to any of several slow changes in an astronomical body's rotational or orbital parameters. An important example is the steady change in the orientation of the axis of rotation of the Earth, known as the precession of the equinoxes.

Gerolamo Cardano (Italian: [dʒeˈrɔːlamo karˈdaːno]; also Girolamo or Geronimo; French: Jérôme Cardan; Latin: Hieronymus Cardanus; 24 September 1501– 21 September 1576) was an Italian polymath whose interests and proficiencies ranged through those of mathematician, physician, biologist, physicist, chemist, astrologer, astronomer, philosopher, music theorist, writer, and gambler. He became one of the most influential mathematicians of the Renaissance and one of the key figures in the foundation of probability; he introduced the binomial coefficients and the binomial theorem in the Western world. He wrote more than 200 works on science.

Cardano partially invented and described several mechanical devices including the combination lock, the gimbal consisting of three concentric rings allowing a supported compass or gyroscope to rotate freely, and the Cardan shaft with universal joints, which allows the transmission of rotary motion at various angles and is used in vehicles to this day. He made significant contributions to hypocycloids - published in De proportionibus, in 1570. The generating circles of these hypocycloids, later named "Cardano circles" or "cardanic circles", were used for the construction of the first high-speed printing presses.