Research On Steady-State Walking Controller Of Humanoid Robot Based On Foot Sensing Information

With the rapid development of science and technology in today’s world,the modernization process of China is also gradually accelerating,and more and more technological equipment has entered the daily life of ordinary people step by step.It has become a feature of the times that machines assist or replace people to complete work.Compared with humans,robots have higher reliability and more stable output efficiency.Especially in some relatively dangerous working environments,robots replace humans to perform tasks and complete work,which greatly protects the safety of human life and avoids many accidental injuries.Humanoid robots have a shape and movement mode similar to humans,however,the movement of robots is driven by power devices and control systems.It makes how to accurately control the stable movement of humanoid robots has become a hot spot in the field of robotics research.More importantly,humanoid robots have the same bipedal upright walking style as humans.A necessary prerequisite for humanoid robots to accurately complete the instructions given by humans and replace humans to complete the work is that the robot can walk stably.The common robot steady-state walking control is to plan the walking gait of the robot through the ZMP stability criterion and the Poincaré mapping gait stability criterion,that is,under the ZMP steady-state judgment condition or the Poincaré map gait steady-state judgment condition,mapping the motion sequence of the robot’s legs is used to realize the stable walking control of the robot.But it is not easy to use them directly to plan the ideal gait.When the robot moves,the plantar pressure information can reflect the stability of the robot,so it can be applied to the steady-state walking control of the robot.It is first necessary to collect the plantar pressure to apply the pressure information.Robots are mostly controlled by DC motors or steering gears,so the limitation of the degree of freedom of the fuselage makes the actions that the robot can perform not comprehensive.By controlling the action of the robot,collecting the plantar pressure of the robot cannot obtain complete and comprehensive data.Based on the above questions,this paper studies how to realize the steady-state walking control of the humanoid robot by the steady-state motion conditions from the plantar pressure information of the human body.Therefore,this paper has carried out the following aspects of work:1.In order to realize the determination of walking stability through the plantar pressure information,this paper starts with the human body,firstly analyzes the walking stability of the human body,and proposes the human body stability determination condition based on the plantar pressure characteristics.By collecting the plantar pressure information of the various motion states of the human body and extracting the characteristics of the plantar pressure,the determination of the walking stability of the human body is realized.2.Aiming at the problem of large plantar pressure measurement errors due to the sparse arrangement of sensors in the human foot pressure acquisition system on the market,and force measuring platforms and force plates which could measure plantar pressure accurately and comprehensively and have high price,can not be exercised the plantar pressure of the motion state.This paper designs a wearable human plantar pressure acquisition system,and completes the related software and hardware design of the system,which solves the above two problems of plantar pressure information collection.3.In order to realize the research of the steady-state walking controller of the humanoid robot based on the plantar pressure information,a humanoid bipedal robot prototype with 19 degrees of freedom was built,and the related software and hardware design of the robot controller was completed.4.The walking stability determination condition based on plantar pressure information is obtained from human body,and then the determination condition is integrated into the walking control of humanoid biped robot.Firstly,the robot is controlled to perform body tilting actions under various gaits.The plantar pressure data of the robot in the critical instability state is collected,and the characteristics of the plantar pressure in this state are extracted.Taking this plantar pressure characteristic as the boundary condition of the robot’s stable walking control,the robot’s steady-state walking control is realized.