616results about How to "Low installation accuracy requirements" patented technology

The invention discloses an electric field type time-grating angular displacement sensor. The electric field type time-grating angular displacement sensor comprises a rotor and a stator, wherein the surface of a base body of the rotor is covered with a circle of dual-sinusoid electrodes which are arranged at equal intervals, the surface of the base body of the stator is evenly covered with a circle of fan-ring-shaped or curved-surface rectangular electrodes, a stator lead are arranged on the bottoms of the electrodes, an insulating layer is arranged between the electrodes and the lead, the surfaces of the electrodes are covered with an insulating protective layer, and thus a multi-layer structure is formed; the base body of the rotor and the base body of the stator are installed coaxially, and a certain gap delta is reserved between the base body of the rotor and the base body of the stator; the base body of the rotor rotates relatively around the axis; the four electrodes in a cycle of the stator are connected with a sinusoidal excitation voltage with a phase of 0 degree, a sinusoidal excitation voltage with a phase of 90 degrees, a sinusoidal excitation voltage with a phase of 180 degrees and a sinusoidal excitation voltage with a phase of 270 degree respectively, the amplitudes and the frequencies of the sinusoidal excitation voltages are equal, and the phases of traveling wave signals Uo generated by the electrodes of the rotor are compared with the phases of a path of fixed-phase reference signals Ur with the same frequency; the phase difference between the two paths of signals is represented by interpolated clock pulses, and an angular displacement value is obtained through conversion. The electric field type time-grating angular displacement sensor is simple in structure and low in power consumption, requirements for mechanical installation precision are low, and free high-precision angle displacement measurement within the range of 360 degrees can be achieved.

A two-freedom air-shooting rotary table using model airplane helicopter as carrier is prepared for using silica gel vibration attenuation material to isolate connection position between suspension support and model airplane helicopter landing gear, applying V belt driving on horizontal rotary mechanism and rope driving on vertical-rotary mechanism, utilizing round rudder disc with edge notch to drive varifocus control rod of DV machine for carrying out varifocus, utilizing model airplane remote control unit to control DV machine to rotate vertically and horizontally as well as to carry out varifocus by shooting personnel.

The invention discloses a method for automatically correcting an initial position of a rotary transformer of an electric vehicle. The method comprises: a motor is in an idle state; according to presetduration time, counter electromotive force signals and rotary transformer position signals of the motor are detected periodically; an average offset value theta1 of the counter electromotive force signals and the rotary transformer position signals during N1 periods as well as an average offset value thetan of the counter electromotive force signals and the rotary transformer position signals during Nn periods is calculated; when the |theta1-thetan|is less than theta0, an initial position of a rotary transformer is adjusted and the adjusting angle is as follows: theta=(theta1+thetan) / 2, wherein the theta0 is an allowable offset value. According to the invention, the offsets of the counter electromotive force signals and rotary transformer position signals are detected when the motor is inan idle state; the initial position of the rotary transformer is corrected and adjusted to ensure the high position precision requirement of the rotary transformer; the installation accuracy requirement and the production cost of the initial position of the rotary transformer are reduced; and the output accuracy of the torque of the motor is improved.