Design Of Wearable Two-dimensional (2D) Hydraulic Electric Pump And Its Controller

In exoskeleton technology,the current power drive modes are hydraulic drive,motor drive and pneumatic drive.But traditional hydraulic drive,especially its hydraulic pump,has the advantages of smooth transmission,light weight,easy to realize miniaturization,and also has the disadvantages of large leakage and obvious noise.In order to improve the performance of hydraulic pump,a two-dimensional(2D)hydraulic electric pump is designed.The quality and volume of the pump are very small,and its anti-pollution ability and volume efficiency are greatly improved compared with the traditional hydraulic pump.In order to drive a two-dimensional(2D)hydraulic electric pump,a special controller is designed to control the motor by using a DC brushless motor with high power and torque.Hall sensor is used to close the speed of the motor,and pressure sensor is used to feedback the closed-loop pressure in the hydraulic system.PID algorithm is used in both control methods.The main research work is as follows:(1)The characteristics of vane pump,screw pump,gear pump and plunger pump are analyzed,the working principle and structure of two-dimensional(2D)hydraulic electric pump are expounded,the main design parameters of two-dimensional(2D)hydraulic electric pump are determined,and the structure design is carried out.Then the flow calculation of two-dimensional(2D)hydraulic electric pump is carried out to illustrate the leakage of the pump.The volume efficiency is calculated theoretically.The mechanical efficiency and total efficiency are calculated by design parameters.Finally,the mechanical analysis and calculation of two-dimensional(2D)hydraulic electric pump are carried out.(2)This paper selects the DC brushless motor to drive the two-dimensional(2D)hydraulic electric pump,and tests various parameters of the DC brushless motor,calculates the efficiency of the selected DC brushless motor,then selects the driver through the working mode of the DC brushless motor,and designs and makes the control board to control the DC brushless motor through the working mode of the driver.The control board is divided into two parts.It is the part of hardware design and software design.Let the control board realize wireless communication between mobile phone and control board,let the control board realize closed-loop of motor speed for testing various functions of 2D electric pump,such as performance parameters,liquid crystal display,etc.Finally,let the control board realize closed-loop of pressure in the system for testing.(3)The test rig of two dimensional(2D)hydraulic electric pump and its controller is built,and the prototype of the two-dimensional(2D)hydraulic electric pump prototype is tested.The feasibility and feasibility of the pump's principle and structure are proved.The pressure pulsation of the hydraulic system is tested through the control loop of the control board,the motor speed is closed by the control board,and the 2D is tested under the condition of the motor's steady speed.Comparing the flow rate of the hydraulic electric pump with the theoretical flow rate,the volumetric efficiency under different loads is obtained.Finally,the whole hydraulic system is tested by closed-loop pressure,and the dynamic response time to the target pressure is measured.Finally,the flow interference characteristics are tested,and the time for the test system to recover to the original pressure is measured..