Papers by Keyword: Gyroscope

Abstract: Obtaining the flight attitude of high accuracy, high reliability is a prerequisite for achieving the autonomous flight of the multi-rotor UAV. MEMS gyroscope can solve attitude angle individually. The paper adopts Euler angle and quaternion algorithms respectively to calculate attitude angle of the multi-rotor UAV. The flight experiment shows that the quaternion algorithm can guarantee the accuracy and the stability of the attitude angle calculation. The root-mean-square errors of the pinch roll and heading angles which are calculated by the quaternion algorithm are 2.947o, 3.606o and 9.769o, which can meet the demand for the autonomous flight of the multi-rotor UAV.

Abstract: ADS8364 is a sixteen-bit parallel output that is sampling and conversion at the same time by six channels. It is a kind of high-precision chip sampling in power. ADS8364 is introduced which combined with practical application of DSP on the attitude and heading reference. ADS8364 which can carry out data collection of six channels is used in the attitude and heading reference for data collection of MEMS sensor of inertial. The data are transmitting to DSP which could complete processing of data and estimate of attitude. By analyzing the results of examination, the precision of MEMS gyroscope’s data which are collected by ADS8364 synchronously could satisfy the request of the attitude and heading reference.

Abstract: Gyroscope is the key component in an Inertial Navigation System (INS). It depends on the precision of the INS. The nonlinear random drift error model based on autoregressive (AR) and genetic programming (GP) was established. The linear model is established based on AR technique. After that, the nonlinear model is built based on GP technique. The result indicates that the square error of the random gyro drift is reduced by 74.5%. The hybrid modeling method can effectively compensate the random gyro drift and improve the stability of the system.

Abstract: The main subject of this thesis is to study a uneasily two-wheeled self-balancing vehicle system. Two tires are placed on two sides of the body parallel in this system . Controlling the rotation of two DC motors can achieve the goal of walking upright. The circuit part is mainly made up by attitude sensors parts (including Gyroscope and Accelerometer), control circuit and the driver board. Attitude sensors measure the tilt angle and the rate of change of inclination of vehicle, and then the controller calculate the responding data and finally drive two DC motors forward or backward to produce forward or backward acceleration to make the car balancing.

Abstract: This paper describes the system activity and the importance of autonomous inertial navigation system /INS/ and its implementation to control the robotic arm. The article further introduces the execution of DC motor regulation utilized for the positioning of a rotary positioned arm. The motor control comprises the current regulation, angular velocity and the rotation of the motor shaft fixed to the arm regarding the required angular change course of the arm rotation. The regulation structure of the DC motor is carried out in MATLAB/Simulink programme. The arm movement is investigated via mathematical model and virtual dynamic model formed in MSC ADAMS programme.

Abstract: The complicated motion of the gyroscope includes the rotation, the precession, the nutation and the sliding motion which are coupled, and it is affected by the lash-force by the whip. Taking the gyroscope which is moving stably as the research subject, according to the motion characteristics of the gyro’s rotation and precession, the gyro is assumed to be the two-force bar, and the coupled relationship of the gyroscope is analyzed quantitatively. The three-dimensional complicated motion in the different categories is analyzed. The nonlinear differential equations in the different categories is derived and linearized by the minor variables method, and then the three-dimensional motion equations on the rotation, precession, nutation and slipping of the gyroscope in the different categories is established. Take the big gym gyroscope as the example, the influence of the force, time and position of the whip on the motion state of the gyroscope is analyzed in detail, and provides the basis for the design of the gyroscope.

Abstract: In this paper, a 4^th-order sigma-delta modulator applied in gyroscope is presented. This modulator adopts the 2-1-1 Multi stage noise shaping structure. The bandwidth of signal is 100 KHz, the over sample rate is 64, and sample frequency is 12.8MHz. By the MATLAB Simulink modeling and simulation, when the input signal is 100 KHz, the SNDR of the MASH ADC is 121.8dB, and the effective number of bit is 19.93 in ideal situation. After considering non-ideal factors, the SNDR is 111.6dB, the effective number of bit of ADC is 18.28. Compared with the ideal situation, the noise floor of PSD has increased 40dB. It explains that non-ideal factors have a significant effect on the performance of the sigma-delta ADC. The 4^th-order MASH sigma-delta modulator has been implemented under 0.5 um CMOS process and simulated under Cadence. The final simulation results show that SNDR is 112.4 dB and effective number of bits (ENOB) is 18.6.

Abstract: MEMS (Microelectromechanical System), as an advanced sensor technology, is low power, low cost, and small size. Gyroscope sensor produced with microelectromechanical technology is an angular rate sensor. IMU (Inertial Measurement Unit) sensor for rocket should have a very wide range of measurements. At the beginning of the motion, the rocket accelereation is very high, for which the rocket IMU requires a multisensor with different sensitivity. This paper presents the design of the rocket IMU and its calibration method for all MEMS gyroscopes. Calibration for each sensor is necessary including its varying characteristics. The calibration of the gyroscope sensors use three-axis motion simulator model ST 3176 with resolutions 0.00001 for all axes. Simultaneous calibration was mutually applied which require a short calibration time. The results show that root mean square errors (RMSE) of the calibrated gyroscope for all axes are under 2.5 %. Therefore, that the calibrated gyroscope can be used in the proposed real application.

Abstract: The accelerometer and gyroscope are used to identify the postural control disease as regards to the posturographic or sway analysis. For example, a gyroscope attached on the waist or head provides the several information such as sway area, sway velocity and others. However, prevalent methods did not describe the optimal position or reliable sensor for analysis. The purpose of this study is to observe and compare characteristics of accelerometers and gyroscopes according to attached positions because it can give the different results. We are assuming a pendulum model when the body sway, the 3-axis calibrated sensor accelerometer and gyroscope were attached on the different positions. From the experimental results, we have confirmed that the reliability of the accelerometers is depends on the position of the pendulum model contrast for the gyroscopes.

Abstract: This paper deals with usability of MEMS sensors for diagnostics of mechatronics system state wirelessly. We can acquire basic kinematics and dynamics mechanism parameters (spatial position, speed, acceleration, vibration, angular rate, orientation, etc.) and some environment condition (local/remote temperature, humidity, pressure, electromagnetic noise) by MEMS sensors. Acquired data are sent to remote application in desktop computer. This system can replace expensive and separate diagnostic tools by small integrated solution with one wireless communication interface (with limitation of MEMS sensors precision). This solution can be battery powered with long operation time, because there is used new wireless technology based on Bluetooth 4 protocol (Low Energy/Smart Bluetooth). Some of integrated MEMS sensors measures same variable on different measuring principle. For example angle can be acquired from three different sensors: magnetometer, accelerometer or gyroscope. Combination of these sensor data can significantly improve value accuracy. The designed diagnostic tool can serve as an inertia measuring unit IMU or Wireless IMU (WIMU).