Research On Intelligent Assisted Robot For Assisting People To Stand Up

As the number of older people and disabled elderly people continue to grow,more and more workers are needed to take care of their daily lives.This way is not only expensive,but also the elderly rarely get meticulous and meticulous care.Due to the muscle atrophy or some diseases of elders,although standing up is the most common exercise in daily life,but it is difficult to complete by themself,which is harmful to their physical and mental health.So the rehabilitation robots have received widespread attention.This thesis proposes a robot that assists the user in completing the standing movement.Firstly,in order to simplify the analysis of the standing process,the lower limbs of the human body are approximated to be bilaterally symmetric,and the standing motion is approximately a bilaterally symmetric motion.In the two-dimensional sagittal plane,the human body is simplified into a three-bar linkage model consisting of the thigh,calf and torso.The D-H method is used to describe the standing position of the standing up process,and the space coordinate system of the simplified human body model is established.Secondly,execute a kinematic analysis of the simplified human body model.The three joint angles of the lower limbs of the human body during the standing process are collected by the sensor,and the acquired angle information is fitted,and the function expressions of the joint angles and the standing time are obtained.The robot link recursive method is used to analyze the lower limb movement of the human body during the standing process.The kinematic parameters including: the trajectory,velocity,angular velocity,acceleration,etc.of each joint and torso.Then,a dynamic analysis of the standing up process is performed.The force/torque of the knee joint is obtained by inverse dynamic analysis.Using the Newton-Eulerian dynamic equilibrium equation to analysis and calculate the kinetic energy and potential energy of the whole system.Simulate with SimMechanics software in MATLAB,and compare the calculation results with the simulation results,the variation feature of the knee joint torque during the standing up process is obtained.Finally,the assisted force provided by the robot is controlled to reduce the pressure on the knee joint during standing up process.Different scale factors are introduced to the research,and the knee joint torque is effectively compensated by actuator control.The force analysis ofthe standing up process,then the actuator speed and acceleration are obtained,finally,the actuators are provided with different assisting forces by different speeds of movement.