Hyperkinesia
A tic can be defined as a repeated, individually recognizable, intermittent movement or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement. These abnormal movements occur with intervening periods of normal movement. These movements are predictable, often triggered by stress, excitement, suggestion, or brief voluntary suppressibility. Many children say that the onset of tics can stem from the strong urge to move. Tics can be either muscular (alter normal motor function) or vocal (alter normal speech) in nature and most commonly involve the face, mouth, eyes, head, neck or shoulder muscles. Tics can also be classified as simple motor tics (a single brief stereotyped movement or movement fragment), complex motor tics (a more complex or sequential movement involving multiple muscle
groups), or phonic tics (including simple, brief phonations or vocalizations).
Langston motor
A Langston or hybrid type of an asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator windings. The motor consists of two stators or two rotors. When the hybrid motor consists of two stators the rotor is placed in the center and similarly when the motor has two rotors then the stator is placed in the center. The windings are similar to that of an induction machine combined with a synchronous machine. A hybrid motor can, therefore, be made without electrical connections to the rotors as are found in universal and DC motors. The motors are fairly new and there is still a lot of research ongoing to investigate if this could be used to drive machines without using V/f-control.