Abstract: A method executable by an autonomous mobile device includes moving in a work environment, obtaining environmental data acquired by a sensing device, and determining whether the sensing device is in a suspected ineffective state based on the environmental data. The method also includes based on a determination that the sensing device is in the suspected ineffective state, rotating at a same location for a first predetermined spin angle. The method also includes obtaining an estimated rotation angle based on one or more motion parameters acquired by a dead reckoning sensor, comparing the estimated rotation angle with the first predetermined spin angle, and based on a determination that a difference between the estimated rotation angle and the first predetermined spin angle is greater than a first predetermined threshold value, executing escape instructions to move backwardly for a first predetermined distance and move along a curve or a folded line.

Abstract: A device for measuring volume of spherical tanks, includes a base, four supporting rods, a driving mechanism, a rotating disc and a counterweight mechanism. The base is provided with a first through hole and a circular fixing base with a second through hole. The supporting rods are circumferentially provided on the fixing base, with a sliding rod slidably provided at the lower side. An outer end of the sliding rod is provided with a limiting plate. The driving mechanism can drive the sliding rods to move simultaneously in radial directions. The rotating disc with a third through hole is arranged on the fixing base, and is rotatably provided with a reel around which a steel tape is wound. A free end of the steel tape is provided with a balancing disc whose opposite sides are provided with laser rangefinders. The counterweight mechanism can keep the balancing disc stable.

Abstract: The present disclosure relates to a DC bus discharge control method, including that: an active discharge instruction is received; a motor current signal is acquired according to the active discharge instruction; the motor current signal is converted into a current signal in a stator coordinate system; a voltage control signal in the stator coordinate system is output based on the current signal in the stator coordinate system and a random current reference instruction of a preset stator coordinate system; and the voltage control signal in the stator coordinate system is converted into a three-phase voltage control signal, and a working state of a switching device is controlled according to the three-phase voltage control signal.

Abstract: The present disclosure relates to a DC bus discharge control method, including that: an active discharge instruction is received; a motor current signal is acquired according to the active discharge instruction; the motor current signal is converted into a current signal in a stator coordinate system; a voltage control signal in the stator coordinate system is output based on the current signal in the stator coordinate system and a random current reference instruction of a preset stator coordinate system; and the voltage control signal in the stator coordinate system is converted into a three-phase voltage control signal, and a working state of a switching device is controlled according to the three-phase voltage control signal.