Research On The Motion Control Of The Spherical Robot For Pipeline Inspection

A spherical robot is a t ype of mobile robot that it has a spherical or ball-like shell,the internal drive device is installed inside the shell.It has advantages of strong sealing,low proportion of space and flexible movement.It is very suitable for driving inside pipelines.In this paper,a new t ype of spherical robot for pipeline environment is designed,its hardware circuit and software control s ystem are designed,and finall y carries out research on the motion control of s pherical robot in pipeline.The main research contents of this paper are as follows:(1)Aiming at the natural gas pipeline environment,a hemispherical differential spherical robot driven b y a double gear rack transmission mechanism s is designed,which has both a full y enclosed space and a closed zone exposed to the pipeline environment.Three-dimensional modeling of the spherical robot is made;the kinematics modeling of the robot is built,which provides theoretical basis for the later motion control;The modeling of the virtual protot ype is developed based on virtual protot yping technology,and the motion simulation of the spherical robot in pipeline is developed b y using ADAMS;Finall y,develops ph ysical protot ype of the spherical robot.(2)The motion control s ystem of the spherical robot is designed,including the hardware circuit and the software.The hardware circuit includes the minimum system circuit,the power suppl y circuit,the communication module circuit and the sensor circuit.In the aspect of the software s ystem,this paper mainl y builds the server software and airborne software,airborne software including the main program and the preparation of each subroutine,server software is mainl y about the design of communication interface.(3)This paper compares the position PID control algorithm with the increment PID control algorithm,selects the increment PID control algorithm as the speed and the attitude control algorithm for the spherical robot.The attitude solution method of spherical robot o ften consists of Euler angle method,direction cosine method,and four-number method,compare s the three algorithms,selects the four-number method as attitude solution method for spherical robot.(4)Set up the experimental environment which includes connecting hardware circuits and the programming as well as setting the pipeline environment.Firstl y,the inertial measurement unit and the attitude solution algorithm are tested,and the experimental results show that the inertial measurement element and the attitude solving algorithm can track the carrier posture effectivel y.Then the spherical robot is placed inside the pipe,the experiment of line ar motion and arc turning motion is carried out.The experimental results show that the designed motion cont rol s ystem has good stabilit y,the effect of the designed motion control algorithm is testified,and the basic motion control of the spherical robot in the pipeline environment is realized.