Auxiliary support method based on variable stiffness supernumerary robotic limbs

An auxiliary support method based on variable stiffness supernumerary robotic limbs, comprising:

• step 1, obtaining in real time original output data from a surface electromyography sensor and an inertial sensor placed on an arm of a wearer;
• step 2, processing data obtained from the inertial sensor to determine whether a human body has an operation intention, and assisting, under a condition that the human body has the operation intention, the human body in supporting an object to a required position by the supernumerary robotic limbs;
• step 3, preprocessing, after the object is in a supported state, original surface electromyography (sEMG) data through full-wave rectification, low-pass filtering and normalization;
• step 4, using preprocessed sEMG data to estimate a reference stiffness of the arm;
• and
• step 5, mapping the reference stiffness of the human arm to an impedance control model of the supernumerary robotic limbs;
• signals provided by the inertial sensor in step 2 comprise a pitch angle, a yaw angle and a roll angle, and the pitch angle is selected as a feature of recognizing the operation intention through a specific computation method as follows:
• {
• T
• =
• 1
• ,
• ❘
• "\[LeftBracketingBar]"
• α
• -
• 60
• ⁢
• °
• ❘
• "\[RightBracketingBar]"
• ≤
• 10
• T
• =
• 0
• ,
• ❘
• "\[LeftBracketingBar]"
• α
• -
• 60
• ⁢
• °
• ❘
• "\[RightBracketingBar]"
• >
• 10
• wherein α represents a pitch angle at a current moment, T=1 indicates that there is an operation intention and T=0 indicates that there is no operation intention.