Lower-limb exoskeleton training method and system triggered by brain-computer interface under motion imagination pattern

Abstract

The invention discloses a lower-limb exoskeleton training method and a lower-limb exoskeleton training system triggered by a brain-computer interface under the motion imagination pattern. The lower-limb exoskeleton training method comprises the following steps: measuring an electrocerebral sample signal of a user according to a preset motion imagination task; carrying out signal preprocessing to eliminate signal noises; carrying out signal conversion by using a common spatial pattern, and extracting and selecting features; establishing an electrocerebral signal classifier template of a user by utilizing the converted signal; and when the user wants to make movement, after the pretreatment in the step 2 and the conversion through the common spatial pattern in the step 3, inputting the real-time motion imagination electrocerebral signal of the user into the electrocerebral signal classifier template obtained in the step 4, deciding the type of the motion imagination electrocerebral signal of the user, and outputting a classification result to a lower-limb exoskeleton controller, so that the lower-limb exoskeleton controller controls the motion movements. With the adoption of the method and the system provided by the invention, the defects that the existing control method is unnatural and limited, and is complicated in design and inconvenient to use are overcome, so that the lower-limb exoskeleton system has strong adaptive capacity and strong control flexibility, and the applicable group is expanded.

Description

technical field [0001] The invention relates to the field of rehabilitation medicine and engineering equipment, in particular to a lower limb exoskeleton training method and system triggered by a motor imagery mode brain-computer interface. Background technique [0002] The lower extremity exoskeleton robot is a physical human-machine coupling system with various types. In terms of function, it can be divided into two types: one is an exoskeleton that assists the elderly, the disabled, and patients with partial loss of motor function to walk; the other One is an exoskeleton that enhances the functions of a normal human body. Different exoskeleton systems have different control methods. The current lower extremity exoskeleton training systems are mainly divided into control methods such as operator control, pre-programmed control, master-slave control, ground reaction force control, and myoelectric signal control. Control methods triggered by electrical signals and brain-com...

AI Technical Summary

Problems solved by technology

[0004] 1. The disadvantage of the operator's control method is that the operator's upper limbs can only be used to issue commands, and cannot perform other activities, and the operator must issue commands continuously, which not only wastes physical strength, but also changes the operator's movement. unnaturally

For patients with partial loss of upper limb motor function, it becomes quite difficult to issue commands

[0005] 2. Some exoskeleton devices operate through pre-programmed programs, and the operator can only perform limited interventions, such as stopping or starting. All these program-based systems require the patient to use a cane or an additional auxiliary frame to maintain the operator Walking is stable, and the forms of movement realized are also very limited

[0006] 3. Master-slave control is generally used in the remote robot operating system. The purpose is to make the remote machine simulate the actions of the operator. This requires that when the system is designed, the activity space for the human and the master exoskeleton should be reserved inside the slave exoskeleton. makes the design of the system quite complex

[0007] 4. The defect of the ground reaction force control method is that its control method is strictly dependent on the dynamic model of the system, and the skeleton suit is a nonlinear system with multiple rigid bodies and multiple degrees of freedom, so it is very difficult to establish an accurate mathematical model

[0008] 5. The EMG control method has its inherent disadvantages: it is impossible to find a one-to-one relationship between the joint torque and the EMG signal of the muscle; in order to determine the relationship between the muscle force and the joint torque, the muscle force arm must is determined, while the moment arm usually varies with the joint angle

Since the strength of the muscle force arm and the EMG signal of the outer surface, and the relationship between the muscle force arm and the muscle force vary with the individual, any controller based on the EMG signal of the outer surface is aimed at a certain operator Personalized equipment; under intense exercise, it is easy to fall off and relocate. After long-term exercise, human body sweating will affect the measurement of the sensor; the sensor must be attached to the surface of the human body every time, which is inconvenient to use

Images