472 results about "Zero drift" patented technology

The embodiment of the invention provides a compensation method and device for holder drift, a holder and an unmanned aerial vehicle, and is applied to the technical field of the unmanned aerial vehicle. The compensation method comprises the following steps: through a first image and a second image collected by an image acquisition device on the holder, obtaining a holder drift angle, and controlling the holder to move to compensate the drift angle. According to the compensation method, the technical problem that the estimation and the compensation of the holder drift cannot be accurately carried out when the zero drift of a gyroscope is compensated is solved.

The invention provides a calibration method, a testing method and a manufacturing method for an optical sensor of a mobile terminal. The calibration method for the optical sensor of the mobile terminal includes the steps of concurrently downloading a calibration plug-in when system software is downloaded through the mobile terminal, then installing the system software on the mobile terminal, providing a testing light source which is provided with a preset light intensity value and correspondingly irradiates the optical sensor, running the calibration plug-in to detect an induction signal generated by the fact that the optical sensor is irradiated by the testing light source, obtaining an induction light intensity value of the induction signal, calculating a calibration parameter according to the induction light intensity value and the preset light intensity value, and accordingly writing the calibration parameter into the mobile terminal. The calibration method is applied to the testing or manufacturing process of each mobile terminal, automatic detection is carried out without peripheral equipment, cost is low, efficiency is high, and as the zero-drift optical sensor and the special light source are adopted, the accuracy is high.

The invention discloses an intelligent pressure transmitter, which is provided with a digital temperature sensor and a pressure sensor. Temperature signals and pressure data can be acquired in real time, the pressure data are converted by an A/D (analog/digital) conversion module and then transmitted to a microcontroller for processing together with the temperature signals, so that temperature compensation, zero drift compensation and nonlinear rectification are realized for the pressure sensor. The intelligent pressure transmitter can overcome the shortcoming of zero drift of a traditional pressure transmitter, and has an excellent zero drift compensation characteristic and a fine time drift suppression characteristic.

The invention relates to an unmanned ship movement control system and method. In the control system, a control module comprises a central controller, a heading controller, a rudder angle controller, a backing controller, a speed controller and an accelerator controller, an information collection module comprises a rudder angle sensor, a speed sensor, a heading sensor, a minigyro, a radar detector and a rudder angel compensator, a power module comprises an engine, a rudder pump device, a water-jet propulsor and a backing pump, and the control system can achieve the functions of trajectory tracking, turning rollover prevention, obstacle avoidance and backing and solves the rudder angle zero drift problem. In the control method, the heading controller is driven to continuously adjust the rudder angle of the rudder pump device through heading angle errors, and operation control of the whole navigation process is achieved; meanwhile, a speed control ring is introduced to assist in long distance target tracking, a rudder angle compensation ring is introduced to overcome rudder angle zero drift in ocean currents, and the minigyro monitors inclination of a hull so as to cooperate with the control module and the power module to achieve safe turn.

The invention discloses a capacitance type sensor with a liquid electrode for measuring the liquid holdup of a multiphase flow, which comprises more than one metal plate with an insulating material coating surface, wherein each metal plate is in contact with the conductive liquid of the measured multiphase flow, and simultaneously, is connected with a measurement circuit by a cathode connector consisting of metal conductors; and the conductive liquid in the multiphase flow serves as the cathode of the capacitance type sensor, and the metal plates with the insulating material coatings form an anode. Therefore, the capacitance and sensitivity of the capacitance type sensor for measuring the liquid holdup of the multiphase flow are greatly improved, the problems of zero drift and ant-interference of the sensor are solved, simultaneously the sensor can be applied to the measurement of the multiphase flows of various flow patterns with flow pattern and size factor-independent measurement results, and is also applied to high-temperature high-pressure occasions.

The invention discloses a subway location method based on an inertial sensor. The location method comprises the steps: (1) collecting starting acceleration of a train through an acceleration sensor of a mobile terminal; (2) determining an initial state of the mobile terminal relative to the train according to gravity acceleration and the starting acceleration, and resolving the acceleration of the train according to the initial state; (3) calculating out a zero-drift vector of an acceleration sensor of the train and a zero-drift vector of a gyroscope sensor of the train; (4) correcting an acceleration component in a train rail direction and calculating out displacement of the train according to the corrected acceleration component in the trail rail direction. According to the location method, high-precision location in a subway can be achieved through a gyroscope of the mobile terminal, an accelerometer of the mobile terminal, an off-line map and an id of a base station cell. The method has the characteristics of being low in cost and high in accuracy, has good application prospect and can solve the problems that an existing mobile terminal map base station is large in location mode error and slow in switch.

The invention discloses an NOx analyzer comprising an infrared light source, a chopper, a detection chamber, optical filters and photoelectric sensor. A separator is arranged between the infrared light source and the chopper; a sealed reference chamber parallel to the detection chamber is arranged between the chopper and the optical filter; infrared light emitted by the infrared light source is divided equally into two bundles of light beams which respectively pass through the detection chamber and the reference chamber through the separator; the optical filters are respectively arranged at light path outlets of the detection chamber and the reference chamber; a sealed optical coupler is arranged at the light path outlet of the optical filter, through which the reference chamber passes; and the light path outlet of the optical coupler leads to the photoelectric sensor which is electrically connected with a processor capable of amplifying and processing an electric signal transmitted by the photoelectric sensor. The invention has the advantages that the influence of water molecule on the measurement is effectively overcome, remarkable zero drift does not exist and a gas detection chamber has stronger corrosion resistance.

The invention relates to a giant magnetoresistance current sensor and relates to a device for measuring currents. The giant magnetoresistance current sensor is composed of an electromagnetic conversion module, a signal amplification module and a feedback compensation module, wherein the electromagnetic conversion module comprises a magnetic core of a magnetism accumulation ring, a primary winding and a giant magnetoresistance chip, the signal amplification module comprises an operational amplifier and a push-pull power amplifier, and the feedback compensation module is a feedback winding. The whole measurement circuit forms a closed loop system, and the giant magnetoresistance chip and the magnetic core of the magnetism accumulation ring form a closed structure. The giant magnetoresistance current sensor overcomes the defects that a giant magnetoresistance current sensor in the prior art is very prone to interference of an external stray magnetic field, temperature drift and zero drift cannot be eliminated completely, and the measurement accuracy is affected by intrinsic magnetic hysteresis existing in a magnetic device.

The disclosed embodiments include a method, apparatus, and computer program product for providing a self-validating mass flow controller or mass flow meter. For example, in one embodiment, a self-validating mass flow controller is disclosed that does not require any software modification to a tool/tool controller in which the mass flow controller is being utilized. In other embodiments, a self-validating mass flow controller is disclosed that does not require any hardware or mechanical changes to an existing mass flow controller. Still, the disclosed embodiments further include a self-validating mass flow controller that is configured to determine valve leak and sensor offset simultaneously for performing real time in-situ correction of a mass flow controller's output for zero offset or zero drift in the presence of valve leak.

The invention discloses a force control method for robotic abrasive belt grinding machining for a blade. The force control method for robotic abrasive belt grinding machining for the blade comprises the following steps: modulation and processing for voltage signals; compensation for a converted force; and a force control strategy. The modulation and processing for the voltage signals comprises thefollowing steps: acquiring the voltage signals of six channels of a sensor; carrying out software filtering on the acquired voltage signals; and converting the filtered voltage signals to force signals. The compensation for the converted force comprises the own zero drift compensation of the sensor and gravity compensation for a robotic end load. The force control strategy comprises hybrid force-position control and PI/PD control. The force control method for robotic abrasive belt grinding machining for the blade is capable of increasing the efficiency of the grinding machining, avoiding thecase of low consistency of manual grinding machining, realizing constant-force grinding machining, and keeping a uniform and consistent removal amount of a surface material, thereby improving the surface consistency of the blade while improving the machining accuracy and surface quality.

The invention provides a zero drift self-adaption method for a pressure sensor of an engine. By means of the method, the zero drift problem of the pressure sensor can be effectively solved, and the control reliability is improved. The method comprises steps as follows: whether the rotating speed of the engine is zero is detected; if yes, a detecting value of zero-point voltage of the pressure sensor is acquired; a difference value between the detecting value of the zero-point voltage of the pressure sensor and the theoretical value is acquired; the voltage value detected by the pressure sensor during operation of the engine is corrected by means of the difference value. Self-adaption of zero drift can be realized, influences of zero drift on electrical control of the engine are eliminated, the engine is accurately controlled, and the performance of the engine is optimized. The influences of zero drift on the detecting result can be effectively reduced by means of a simple control program, so that the service life of the pressure sensor is prolonged. Compared with a mode of circuit hardware modification, the method has the advantages that the cost for hardware purchase and time required for circuit modification are saved, and the method is more economical and efficient.

The invention discloses a torque limiting system of a folding-arm type lorry-mounted crane. The torque limiting system comprises a sensor part, a processor part and a performer part, wherein the sensor part consists of a weight sensor, a length measuring sensor and two angle sensors, the processor part calculates the rated lifting capacity under the current working condition according to sensor signals and compares the rated lifting capacity with an actually-measured lifting capacity, and the performer part sends out alarm signals or limits dangerous operations when alarming or limiting conditions are reached. The torque limiting system of the folding-arm type lorry-mounted crane has the advantages that the inconvenience in the input of a rated working curve and incompleteness of curve expression are avoided; the torque limitation under any working condition of lifting from the tail end of a lifting arm can be performed, and the functions are comprehensive; and as the weight sensor is adopted to directly measure weight, the calculation error caused by factors such as zero drift and delay when a pressure sensor is adopted is avoided, and the accuracy is high.

The invention discloses an automatic zero drift-correction ultrasound water meter and a correction method. The apparatus comprises a zero flow auxiliary correction transducer set. The zero flow auxiliary correction transducer set can detect ultrasound wave spreading time difference without the interference of flow, is connected with a signal receiving-sending conversion device via a signal and send data to a signal processing and displaying device. The correction method works in a way that according to time difference detected by a measuring transducer set and an auxiliary transducer set via the signal processing and displaying device. Compared with the prior art, zero drift influence quantity in the measuring result can be eliminated, so ultrasound water meter measuring accuracy can be maintained.

The invention discloses a method for improving the weighing precision of a charging system and a device thereof. The method comprises the following steps of: additionally installing a preset compensation module on a weighing hopper to generate an original weighting value, wherein the standard weight of the preset compensation module is larger than the maximum positive zero drift value and the maximum negative zero drift value of the weighing hopper; computing to obtain the current practical value of the material on the weighing hopper according to the original weighting value and the weighing detection value of the weighing hopper; stopping vibrating a high-level stock bin when the current practical value is near to a set material adding value; and discharging the material out of the weighing hopper after the weighing detection value is stable and invariable. The device corresponds to the method. By being additionally provided with the compensation module, the invention simply and skillfully overcomes the problem that the weighing is inaccurate caused by the zero drift, improves the weighing precision of the charging system, and can not increase the production cost.

Disclosed is a digital signal conditioning chip of a full-bridge and piezoresistive pressure sensor, which mainly comprises a bandgap reference voltage module, an adjustable gain calculation amplifier module and a digital control unit module. The invention is characterized in that a positive temperature coefficient voltage is generated in the bandgap reference voltage module to provide an energizing voltage for the full-bridge and piezoresistive pressure sensor, the digital control unit module is equipped with a memory and an inner clock circuit, the gain in the adjustable gain switch capacity calculation amplifier is confirmed by the digital control unit module according to the parameter of positive temperature coefficient, zero temperature coefficient and zero output value. The digital signal conditioning chip of a full-bridge and piezoresistive pressure sensor has the advantages that the conditioning chip realizes effect compensation of sensitivity, zero drift compensation and adjustment of zero output, and is high in conditioning accuracy and low in cost.