| Among the large family of sensors,tilt sensors play an important role in attitude measurement.A part of tilt sensors on the market can only be used for inclination measurement in static systems.There are some tilt sensors which can be used in the dynamic system,but they are relatively expensive.In the future era of Internet of Things,the traditional sensor is far below the level required by the Internet of Things.Therefore,it is very meaningful to design a new type of practical tilt sensor in practice.In this paper,a new type of bionic dynamic tilt sensor is designed and a new structure of ball tilt sensor is explored.In this paper,using the principle of bionics,a new type of uniaxial cylinder dynamic tilt sensor is designed and a new structure of multi-axis spherical tilt sensor is explored.Firstly,a biomimetic dynamic uniaxial cylindrical inclination sensor is designed,which is composed of a damping plate,a cylindrical shell,a damping liquid,an E-type ferrite,a ring type ferrite and a rotating shaft.The key part of the structural design:one,the use of ferrite ring fixed to the internal damping plate;Second,the annular ferrite axis and the internal damping plate rotation axis does not coincide,but the two axes are parallel,that is,the rotor part of the sensor is an eccentric structure.By the magnetic circuit analysis within the sensor shows that when the sensor rotation occurs,the coil inductance changes,the inductance is not easy to measure,a waveform conversion circuit is designed,so that the tilt is converted to the corresponding frequency.In order to measure the frequency value,a data acquisition module is designed to collect the frequency data by the programmable counting array(PCA)of C8051 single-chip.The collected data is sent to the upper computer through the TTL serial port and displayed on the upper computer interface.Because the uniaxial cylinder tilt sensor can only measure the uniaxial inclination,a multi-axis spherical tilt sensor has been designed.According to two kinds of non-electric transformation schemes of reluctance and image,two kinds of spherical tilt sensors with multi-axis reluctance and multi-axis images are designed.Since the multi-axial reluctance tilt sensor is based on a single-axis tilt sensor,it is mainly composed of the outer shell,damping fluid,spherical ferrite and E-type ferrite composition.In principle,it is similar to the measurement of uniaxial cylinder sensors,but also the inclination value is converted into the corresponding frequency,the frequency value is collected and displayed.Multi-axis image tilt sensor is mainly composed of outer spherical shell,inner ball,stepper motor,the coupling,image acquisition module,and bracket and chassis.The ball is located in the spherical cavity of the outer spherical shell.The image acquisition module is fixed at the north pole of the outer spherical shell.When the sensor rotates,the inner ball slides toward the new equilibrium position under the action of gravity.The image acquisition module mainly uses color recognition and Color tracking method to locate the ball,through the TTL serial print output ball coordinates,combined with the auxiliary positioning mark point to calculate the sensor rotation angle.Finally,the integrated experimental platform of single-axis cylindrical and multi-axis spherical tilt sensors was designed respectively,and a physical prototype was set up for experiments.The collected experimental data and theoretical data for simulation in MATLAB,the comparison between the experimental data of single-axis cylindrical tilt sensor and the theoretical data shows that the agreement between experimental data and theoretical data is high,which proves the validity of the designed tilt sensor,the results can be seen from the translational motion,the sensor has a certain restraining effect on translation noise.The measurement error of the multi axis spherical angle sensor is less than 3 degrees,and the measurement accuracy can be improved by combining the visual reference system AprilTag. |
PDF Full Text Request