Research On The Contact Force Control System Between The Disc Brush And The Lampshade For Street Lamp Cleaning

After a street lamp has been used for a period of time,dust particles continue to deposit,which affects the lighting effect and driving safety.So the street lamp should be cleaned regularly.At present,the street lamp is mostly cleaned manually or semi-automatically,which poses certain safety risks.And it is difficult to meet the maintenance requirements of lighting equipment.The research is conducted on the key technology that affects cleaning in the process of cleaning street lights-the contact force control system between the disk brush and the lampshade.The adhesion mechanism of dust particles on the surface of the lampshade is analyzed.The adjustment mechanism of disc brush contact force and its contact force control system is designed.And the street lamp cleaning experiment platform is built to verify the rationality of the contact force control system.The main contents are as follows:(1)The dust adhesion mechanism on the surface of the lampshade is analyzed.The order of magnitude of the adhesion of a single dust particle based on the mathematical model is deduced.Combining the distribution of dust particles on the surface of the lampshade,the order of magnitude of the adhesion of all dust particles on the surface of the lampshade is obtained.Then the way of cleaning dust particles on the surface of the lampshade is determined.The expected cleaning pressure between the disc brush and the lampshade is obtained.(2)According to the actual application of street lamp cleaning,the adjustment mechanism of the disc brush contact force is designed,including automatic cleaning unit,contact force adjustment unit,and bracket unit.The main connection parts are checked for strength and key components are selected and calculated.Used the principle of impedance control,the disc brush contact force control system is designed and the force/position sensors are selected.(3)The mathematical model of the contact force control system of the disc brush is established.According to the mathematical model,it is divided into the zero-force free end stage and the fixed force end stage.The influence of the spring equivalent stiffness in the internal parameters of the control system on the open-loop system is analyzed through the Bode diagram.And the disc brush contact force control system is analyzed through the closed-loop characteristic parameters.Then determining the impedance control parameters:the inertia coefficient md is often selected within a certain range of the actual load mass,and the stiffness coefficient kd is determined according to the response speed of the force control outer loop and the steady-state value of the position correction deviation,and damping coefficient bd≥2(?).The simulation analysis of cleaning the surface of the lampshade with the disc brush is carried out,and the results show that the cleaning pressure between disc brush and the surface of the lampshade is finally stabilized at the desired cleaning pressure.Finally,it is pointed out that the detection error of the bristle stiffness and the lampshade position can cause the input signal error of the control system,which result in the actual cleaning pressure to fluctuate around the expected cleaning pressure value.(4)The stability and effectiveness of the disc brush contact force control system are verified through street lamp cleaning experiments.The cleaning experiment platform is built,measuring and calculating the equivalent rigidity of the disc brush.The relationship between the deformation of the bristles and the cleaning pressure is obtained.Fixing the distance between the disc brush and the lampshade,the change of the output displacement of the disc brush and the cleaning pressure is analyzed when the disc brush is stationary and rotating.The results show that the output displacement of the disc brush and the cleaning pressure are stable near the expected value.