A phase calibration method for coordinating exoskeletons and construction tools

Abstract

This invention relates to the technical field of exoskeleton and construction tool coordination, and discloses a phase calibration method for exoskeleton and construction tool coordination. The method includes attaching electrodes and a first sensor to the muscle groups of a construction worker, and attaching a second sensor to the handle of the construction tool. The construction worker uses the tool to perform a task: when the worker is not wearing the exoskeleton, a first signal set is collected; when the worker is wearing the exoskeleton, a second signal set is collected; a muscle activation timing reference value is set based on the first signal set; based on the second signal set and the muscle activation timing reference value, the phase difference between the first and second electrode signals is determined, and the triggering time of the exoskeleton's auxiliary force is calibrated based on the phase difference to bring the phase difference close to zero. This invention's phase calibration method for exoskeleton and construction tool coordination achieves synchronization between exoskeleton auxiliary force and human force exertion by aiming for a phase difference close to zero, avoiding the phenomena of arm-mounted or weight-bearing loads.

Description

Technical Field

[0001] This invention relates to the technical field of coordination between exoskeletons and construction tools, and in particular to a phase calibration method for coordinating exoskeletons and construction tools. Background Technology

[0002] Exoskeletons, as wearable assistive devices, can provide power assistance to construction workers and reduce labor intensity. To evaluate the coordination between exoskeletons and construction tools, existing technologies typically use indicator systems for assessment, including indicators such as task completion time, number of operational errors, and fatigue level scores.

[0003] However, in complex environments such as mountainous areas, construction workers often need to use vibratory construction tools such as electric drills, cutting machines, and impact drills. The following problems arise when using vibratory construction tools:

[0004] (1) There is a phase difference between the timing of the exoskeleton's power-assisted output and the natural joint movement cycle of the human body. When the exoskeleton's auxiliary force intervenes too early, it will lift the worker's arm, making it difficult to align the tool with the work surface; when it intervenes too late, the worker will have to bear the entire load alone, increasing the burden on their muscles. This phase mismatch cannot be reflected by traditional indicators such as task completion time or the number of operational errors.

[0005] (2) The force exertion pattern and activation speed of human muscles differ significantly under different working directions (upward working, horizontal working, downward working). The same exoskeleton parameters will produce completely different auxiliary effects in different directions.

[0006] (3) Vibration-type construction tools generate high-intensity vibrations during use. These vibrations are transmitted through the hands to key muscle groups, causing mechanical interference to the electromyography (EMG) signal acquisition electrodes. When the interfered EMG signal is compared with the reference value, the interference signal masks the true muscle force signal, leading to incorrect peak identification and distorted phase difference. Calibration based on the distorted phase difference will cause the exoskeleton's auxiliary force phase to be adjusted to the wrong direction, rendering the entire phase calibration method ineffective. Summary of the Invention

[0007] Therefore, the purpose of this invention is to overcome the problem that vibrations generated by vibrating construction tools can interfere with the acquisition of electromyographic (EMG) signals, causing the phase recognition method based on EMG signals to fail. This invention proposes a phase calibration method for coordinating exoskeleton and construction tools. By acquiring vibration signals from the construction tool handle and using them for interference separation, the method overcomes the interference of vibration on EMG signals, establishes a muscle activation timing reference value, and then calibrates the triggering time of the exoskeleton's auxiliary force using the phase difference calculated from the muscle activation timing reference value. By aiming for the phase difference to approach zero, the method achieves synchronization between the exoskeleton's auxiliary force and the human body's force exertion, avoiding the phenomenon of arm extension or weight-bearing.

[0008] To address at least one of the aforementioned technical problems, the present invention provides a phase calibration method for coordinating exoskeletons and construction tools, comprising:

[0009] Electrodes and a first sensor are attached to the muscle groups of the construction workers, and a second sensor is attached to the handle of the construction tool; all sensors are acceleration sensors; the construction tool is a vibration-type construction tool.

[0010] Construction workers can use construction tools to perform tasks in different working directions: when the construction workers are not wearing exoskeletons, a first signal set is collected; when the construction workers are wearing exoskeletons, a second signal set is collected; wherein, the signal set includes signals collected by electrodes, a first sensor, and a second sensor;

[0011] Set muscle activation timing reference values ​​for different working directions based on the first signal set;

[0012] Based on the second signal set and the muscle activation timing reference value, the phase difference between the first electrode signal and the second electrode signal is determined, and the triggering time of the exoskeleton assistive force is calibrated according to the phase difference so that the phase difference approaches 0.

[0013] Preferably, the muscle groups are determined based on the construction tools, work direction, and work tasks;

[0014] The working direction can be an upward working direction, a downward working direction, or a horizontal working direction: when the angle between the working direction and the horizontal line is [-45, 45], it is a horizontal working direction; when the angle between the working direction and the horizontal line is [-90, -45), it is a downward working direction; when the angle between the working direction and the horizontal line is (45, 90], it is an upward working direction.

[0015] The vibrating construction tool is a construction tool that generates vibration during use and transmits it to the arm of the construction worker;

[0016] The electrodes are used to collect raw muscle electrical signals from construction workers;

[0017] The first sensor is used to collect muscle vibration signals from construction workers;

[0018] The second sensor is used to collect vibration signals from the handle of the construction tool;

[0019] The first signal set includes a first muscle electrical signal, a first muscle vibration signal, and a first handle vibration signal;

[0020] The second signal set includes a second muscle electrical signal, a second muscle vibration signal, and a second handle vibration signal.

[0021] Preferably, the method for setting the muscle activation timing reference value includes:

[0022] Based on the first muscle vibration signal and the first handle vibration signal, determine the first amplitude ratio and the first time delay between the handle vibration signal and the muscle vibration signal;

[0023] Based on the first amplitude ratio, the first time delay, and the first handle vibration signal, predict the first vibration interference signal;

[0024] The first pure muscle electrical signal is determined based on the difference between the first muscle electrical signal and the first vibration interference signal.

[0025] The time interval from the start of the task to the first time the first pure muscle electrical signal exceeds the first activation threshold is used as the muscle activation timing reference value; wherein, the activation threshold is determined based on the root mean square of the muscle electrical signal of the muscle group in the resting state.

[0026] Preferably, the method for determining the start time of the operation includes:

[0027] The moment when the power supply current of the construction tool changes abruptly from zero to the working current is taken as the start time of the operation;

[0028] Alternatively, the moment when the acceleration changes abruptly as detected by the second sensor can be taken as the start time of the operation.

[0029] Preferably, the method for determining the amplitude ratio includes the following formula:

[0030] ;

[0031] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The amplitude ratio; This is the root mean square of the muscle vibration signal; This is the root mean square of the handle vibration signal.

[0032] Preferably, the method for determining the time delay includes: taking the time offset at which the cross-correlation function of the muscle vibration signal and the handle vibration signal reaches its maximum value as the time delay;

[0033] The cross-correlation function includes the following formula:

[0034] ;

[0035] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number is an integer in [1, J]. This represents the total number of sampling points; This is the time offset; For the first Cross-correlation function of sampling points; For the first Muscle vibration signals at the sampling points; for The vibration signal of the handle at a given time, where The sampling frequency.

[0036] Preferably, the method for predicting vibration interference signals includes the following formula:

[0037] ;

[0038] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number; For time delay; for Vibration interference signal at the sampling time; The unit conversion factor represents the interference voltage generated in the electromuscular signal by vibration under unit gravitational acceleration; The amplitude ratio; for The vibration signal of the handle at any given moment.

[0039] Preferably, the method for determining the unit conversion factor includes:

[0040] Acquire the third electromyographic signal in the first time period, the fourth electromyographic signal in the second time period, and the fourth handle vibration signal; wherein, the first time period is from when the construction worker raises the construction tool and faces the construction surface to before the construction tool is powered on and started; the second time period is from when the construction tool leaves the construction surface and faces the construction surface to before the construction tool is powered off and turned off.

[0041] Subtracting the third muscle electrical signal from the fourth muscle electrical signal yields the first difference;

[0042] The unit conversion factor is determined based on the reciprocal of the amplitude ratio and the ratio of the first difference to the vibration signal of the fourth handle.

[0043] Preferably, the method for determining the phase difference includes:

[0044] Based on the second muscle vibration signal and the second handle vibration signal, determine the second amplitude ratio and the second time delay between the handle vibration signal and the muscle vibration signal;

[0045] Based on the second amplitude ratio, the second time delay, and the second handle vibration signal, predict the second vibration interference signal;

[0046] The second pure muscle electrical signal is determined based on the difference between the second electromuscular signal and the second vibration interference signal.

[0047] The time interval from the start of the task to the moment when the second pure electromyographic signal first exceeds the second activation threshold is taken as the muscle activation timing value.

[0048] The difference between the muscle activation timing value and the muscle activation timing reference value is taken as the phase difference.

[0049] Preferably, the method for correcting the triggering time of the exoskeleton assistive force includes:

[0050] If the difference between the muscle activation timing value and the muscle activation timing baseline value is negative, it indicates that the intervention of the exoskeleton auxiliary force is delayed. In this case, the triggering time of the auxiliary force will be advanced, and the advance will be equal to the absolute value of the phase difference.

[0051] If the difference between the muscle activation timing value and the muscle activation timing baseline value is positive, it indicates that the exoskeleton assist force intervention is ahead of schedule. In this case, the triggering time of the assist force will be delayed, and the delay will be equal to the absolute value of the phase difference.

[0052] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0053] The phase calibration method for coordinating exoskeletons and construction tools described in this invention overcomes the interference of vibration on muscle electrical signals by collecting vibration signals from the handle of the construction tool for interference separation. It establishes a muscle activation timing reference value and aims to approach zero phase difference, calibrating the triggering time of the exoskeleton's auxiliary force based on this phase difference. This achieves synchronization between the exoskeleton's auxiliary force and the human body's force exertion, avoiding the phenomenon of extended arms or heavy loads, and improving the wearing experience and work efficiency of construction workers. Specifically:

[0054] By simultaneously attaching accelerometers to the muscle groups of construction workers and the handles of construction tools, dual monitoring of the vibration interference source and transmission path is achieved. This facilitates subsequent separation of the vibration signal from the tool handle from the interference, overcoming the interference of vibration on muscle electrical signals and ensuring the accuracy of the muscle activation timing reference values.

[0055] By collecting signal sets when the exoskeleton is not worn and when it is worn, a comparison benchmark is established between the unassisted and assisted states. This can identify the phase mismatch between the timing of exoskeleton assistance and the natural joint movement cycle of the human body, providing a quantitative basis for calibrating the triggering time of exoskeleton assistance and achieving timing synchronization.

[0056] By setting muscle activation timing benchmark values ​​for different work directions such as upward, horizontal, and downward work, the differences in muscle force exertion patterns and activation speeds in different directions are fully considered, ensuring that the calibration results remain accurate under different work directions and expanding the applicability of the method. Attached Figure Description

[0057] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0058] Figure 1 This is a schematic flowchart of a phase calibration method for coordinating exoskeletons and construction tools in an embodiment of the present invention.

[0059] Figure 2 This is a schematic diagram of one direction of construction in an embodiment of the present invention. Detailed Implementation

[0060] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0061] Example 1: This example provides a phase calibration method for coordinating exoskeletons and construction tools.

[0062] refer to Figure 1The phase calibration method for coordinating exoskeleton and construction tools in this embodiment includes steps SS1 to SS4.

[0063] Step SS1: Attach electrodes and the first sensor to the muscle group of the construction worker, and attach the second sensor to the handle of the construction tool.

[0064] When applying this method, the muscle groups of construction workers are determined based on the construction tools, the direction of work, and the task at hand.

[0065] refer to Figure 2 The working direction includes upward, downward, or horizontal working directions. When the angle between the working direction and the horizontal line is [-45°, 45°], it is a horizontal working direction; when the angle between the working direction and the horizontal line is [-90°, -45°], it is a downward working direction; and when the angle between the working direction and the horizontal line is (45°, 90°], it is an upward working direction.

[0066] The construction tool is a vibratory construction tool. Furthermore, the vibratory construction tool is configured to generate vibration during use and transmit it to the construction worker, for example, to the worker's arm. Vibratory construction tools can be electric drills, cutting machines, angle grinders, marble cutters, impact drills, etc. When the construction tool is an electric drill, the task can be drilling upwards, horizontally, or downwards.

[0067] When the task is upward drilling, the muscle groups involved include the anterior deltoid, triceps brachii, and forearm flexors. The anterior deltoid is associated with lifting, the triceps brachii with pushing, and the forearm flexors with holding the drilling tools. When the task is horizontal drilling, the muscle groups involved include the pectoralis major, triceps brachii, and forearm flexors. The pectoralis major is associated with pushing forward, the triceps brachii with extension, and the forearm flexors with holding the drilling tools. When the task is downward drilling, the muscle groups involved include the posterior deltoid, biceps brachii, and forearm flexors. The posterior deltoid is associated with pulling down, the biceps brachii with controlling the downward movement, and the forearm flexors with holding the drilling tools.

[0068] In practical applications, both the first and second sensors are accelerometers. The first sensor is used to collect muscle vibration signals from construction workers, while the second sensor is used to collect vibration signals from the handles of construction tools.

[0069] Furthermore, the electrodes can be gold electrodes or dry electrodes. Further, the electrodes are used to acquire raw electromyographic signals from the construction worker. Even further, the distance between the electrodes and the first sensor is 1 cm to 2 cm.

[0070] In practice, the second sensor at the handle of the construction tool directly measures the vibration source signal, while the first sensor at the muscle group measures the vibration signal transmitted through the human body. The combination of these two sensors forms a monitoring link along the transmission path between the vibration source and the interference point. By setting up dual sensors and electrodes, a reference benchmark is provided for calculating vibration interference, enabling the differentiation between active muscle exertion and passive vibration interference, thus providing a basis for subsequent vibration interference separation.

[0071] Step SS2: Have construction workers perform tasks in different working directions using construction tools: collect the first signal set when construction workers are not wearing exoskeletons; collect the second signal set when construction workers are wearing exoskeletons.

[0072] In application, when construction workers are not wearing exoskeletons, they are instructed to perform standard actions using construction tools in a designated work direction, and a first signal set is collected. When construction workers are wearing exoskeletons, they are instructed to perform standard actions using construction tools in a designated work direction, and a second signal set is collected.

[0073] In practical applications, different working directions have corresponding first and second signal sets. The signal sets include signals collected by the electrodes, the first sensor, and the second sensor. Specifically: the first signal set includes a first electromyographic signal, a first muscle vibration signal, and a first handle vibration signal; the second signal set includes a second electromyographic signal, a second muscle vibration signal, and a second handle vibration signal.

[0074] Step SS3: Set the muscle activation timing reference values ​​for different working directions based on the first signal set.

[0075] When applied, different working directions have corresponding muscle activation timing reference values.

[0076] In practical applications, the method for setting the muscle activation timing reference value includes steps SS31 to SS34.

[0077] Step SS31: Based on the first muscle vibration signal and the first handle vibration signal, determine the first amplitude ratio and the first time delay between the handle vibration signal and the muscle vibration signal.

[0078] In application, the amplitude ratio reflects the degree of amplitude attenuation during the transmission of vibration from the tool handle to the muscle. Furthermore, the amplitude ratio varies depending on the muscle location and the direction of operation. Specifically, the amplitude ratio is determined using the following formula:

[0079] ;

[0080] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The amplitude ratio; This is the root mean square of the muscle vibration signal; This is the root mean square of the handle vibration signal.

[0081] when When the value is 0, This is the first amplitude ratio; The root mean square of the first muscle vibration signal; This is the root mean square of the vibration signal from the first handle. When... When the value is 1, This is the second amplitude ratio; The root mean square of the second muscle vibration signal; This is the root mean square of the vibration signal of the second handle.

[0082] In practical applications, time delay is used to reflect the time required for vibration propagation. Taking the physical delay of vibration transmission into account allows for the alignment of vibration disturbance predictions along the time axis. Furthermore, methods for determining time delay include using the time offset at which the cross-correlation function of the muscle vibration signal and the handle vibration signal reaches its maximum value as the time delay.

[0083] The cross-correlation function includes the following formula:

[0084] ;

[0085] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number; This represents the total number of sampling points; This is the time offset; For the first Cross-correlation function of sampling points; For the first Muscle vibration signals at the sampling points; for The vibration signal of the handle at any given moment. The sampling frequency is specified. In some embodiments, the effective energy of human muscle electrical signals is concentrated between 20Hz and 500Hz. When the dominant vibration frequency of construction tools such as electric drills is between 100Hz and 400Hz, It can be 2000Hz.

[0086] when When the value is 0, the aforementioned cross-correlation function is the first cross-correlation function of the first muscle vibration signal and the first handle vibration signal; the time offset when the first cross-correlation function reaches its maximum value is used as the first time delay. When the value is 1, the above cross-correlation function is the second cross-correlation function of the second muscle vibration signal and the second handle vibration signal; the time offset when the second cross-correlation function reaches its maximum value is used as the second time delay.

[0087] Step SS32: Predict the first vibration interference signal based on the first amplitude ratio, the first time delay, and the first handle vibration signal.

[0088] In application, using the vibration source signal as a reference, effective separation can be achieved even when the muscle signal and vibration signal frequency bands overlap. Specifically, the prediction method for vibration interference signals includes the following formula:

[0089] ;

[0090] In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number; For time delay; for Vibration interference signal at the sampling time; The unit conversion factor represents the interference voltage generated in the electromuscular signal by vibration under unit gravitational acceleration; The amplitude ratio; for The vibration signal of the handle at any given moment.

[0091] when When the value is 0, This is the first vibration interference signal; This is the first unit conversion factor. When When the value is 1, This is the second vibration interference signal. This is the conversion factor for the second unit.

[0092] In practical applications, the method for determining the unit conversion factor includes steps SS321 to SS323.

[0093] Step SS321: Acquire the third electromyographic signal of the first time period, the fourth electromyographic signal of the second time period, and the fourth handpiece vibration signal.

[0094] In application, the first time period is from when the construction worker raises the construction tool and faces the construction surface until the tool is powered on and started. The second time period is from when the construction tool is removed from the construction surface and faces the construction surface until the tool is powered off.

[0095] In practical applications, when the construction worker is not wearing the exoskeleton, step SS321 is executed for the subsequent calculation of the first unit conversion factor; when the construction worker is wearing the exoskeleton, step SS321 is executed for the subsequent calculation of the second unit conversion factor.

[0096] Step SS322: Subtract the third muscle electrical signal from the fourth muscle electrical signal to obtain the first difference.

[0097] When applied, the first difference = the average value of the fourth muscle electrical signal in the second time period - the average value of the third muscle electrical signal in the first time period.

[0098] Step SS323: Determine the unit conversion coefficient based on the reciprocal of the amplitude ratio and the ratio of the first difference to the vibration signal of the fourth handle.

[0099] When applying this method, the unit conversion factor includes the following formula:

[0100] ;

[0101] In the formula, This is the unit conversion factor; The amplitude ratio; It is the worst; This represents the average value of the vibration signal of the fourth handle during the second time period.

[0102] Step SS33: Determine the first pure muscle electrical signal based on the difference between the first muscle electrical signal and the first vibration interference signal.

[0103] In application, the first pure electromyographic signal = the first electromyographic signal - the first vibration interference signal.

[0104] In practical applications, pure muscle electrical signals retain complete information about muscle exertion.

[0105] Step SS34: The time interval from the start of the task to the first time the first pure muscle electrical signal exceeds the first activation threshold is used as the muscle activation timing reference value.

[0106] In application, the start time of the operation can be determined by taking the moment when the power supply current of the construction tool abruptly changes from zero to the operating current. Alternatively, the start time can be determined by taking the moment when the acceleration detected by the second sensor abruptly changes. The timing of the power supply current abrupt change is strictly synchronized with the operator's action of pressing the switch, eliminating reaction time errors caused by external commands.

[0107] In practical applications, the activation threshold is determined based on the root mean square (RMS) of the muscle electrical signal at rest. Specifically, the activation threshold can be three times the RMS of the muscle electrical signal at rest. The probability of the instantaneous value of the muscle electrical signal exceeding three times the RMS at rest is extremely low. Therefore, when the muscle electrical signal exceeds the activation threshold, it can be confidently determined that the muscle has begun to activate, rather than being a false trigger caused by noise. Even with minor environmental electromagnetic interference or electrode contact noise, it will not lead to misjudgment of the muscle activation timing baseline.

[0108] Step SS4: Based on the second signal set and the muscle activation timing reference value, determine the phase difference between the first electrode signal and the second electrode signal, and calibrate the triggering time of the exoskeleton assistive force according to the phase difference so that the phase difference approaches 0.

[0109] When applied, the method for determining the phase difference includes steps SS41 to SS45.

[0110] Step SS41: Determine the second amplitude ratio and the second time delay between the handle vibration signal and the muscle vibration signal based on the second muscle vibration signal and the second handle vibration signal.

[0111] For specific application details, please refer to step 31; further details will not be provided here.

[0112] Step SS42: Predict the second vibration interference signal based on the second amplitude ratio, the second time delay, and the second handle vibration signal.

[0113] For specific application details, please refer to step 32; these will not be repeated here.

[0114] Step SS43: Determine the second pure muscle electrical signal based on the difference between the second muscle electrical signal and the second vibration interference signal.

[0115] For specific application details, please refer to step 33; further details will not be provided here.

[0116] Step SS44: The time interval from the start of the task to the moment when the second pure muscle electrical signal first exceeds the second activation threshold is taken as the muscle activation timing value.

[0117] Step SS45: The difference between the muscle activation timing value and the muscle activation timing reference value is taken as the phase difference.

[0118] When applied, the phase difference = muscle activation timing value - muscle activation timing baseline value.

[0119] The method for correcting the triggering time of the exoskeleton assistive force in step SS4 includes steps SS46 to SS47.

[0120] Step SS46: If the difference between the muscle activation timing value and the muscle activation timing baseline value is negative, that is, the phase difference is negative, it indicates that the intervention of the exoskeleton auxiliary force is delayed. In this case, the triggering time of the auxiliary force is advanced, and the advance is equal to the absolute value of the phase difference.

[0121] Step SS47: If the difference between the muscle activation timing value and the muscle activation timing baseline value is positive, that is, the phase difference is positive, it indicates that the exoskeleton assistance force intervention is ahead of schedule. In this case, the triggering time of the assistance force will be delayed, and the delay will be equal to the absolute value of the phase difference.

[0122] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A phase calibration method for coordinating exoskeletons and construction tools, characterized in that, include: Electrodes and a first sensor are attached to the muscle groups of the construction workers, and a second sensor is attached to the handle of the construction tool; all sensors are acceleration sensors; the construction tool is a vibration-type construction tool. Construction workers use construction tools to perform tasks in different working directions: when the construction workers are not wearing exoskeletons, a first signal set is collected; when the construction workers are wearing exoskeletons, a second signal set is collected; wherein, the signal set includes signals collected by electrodes, a first sensor, and a second sensor; Set muscle activation timing reference values ​​for different working directions based on the first signal set; Based on the second signal set and the muscle activation timing reference value, the phase difference between the first electrode signal and the second electrode signal is determined, and the triggering time of the exoskeleton assistive force is calibrated according to the phase difference so that the phase difference approaches 0. The method for setting the muscle activation timing baseline value includes: Based on the first muscle vibration signal and the first handle vibration signal, determine the first amplitude ratio and the first time delay between the handle vibration signal and the muscle vibration signal; The first vibration interference signal is predicted based on the product of the first amplitude ratio, the first time delay, and the first handle vibration signal. The first pure muscle electrical signal is determined based on the difference between the first muscle electrical signal and the first vibration interference signal. The time interval from the start of the task to the first time the first pure muscle electrical signal exceeds the first activation threshold is used as the muscle activation timing reference value; wherein, the activation threshold is determined based on the root mean square of the muscle electrical signal of the muscle group in the resting state. Methods for determining the time delay include: using the time offset at which the cross-correlation function of the muscle vibration signal and the handle vibration signal reaches its maximum value as the time delay; The cross-correlation function includes the following formula: ； In the formula, when A value of 0 indicates that the construction worker is not wearing an exoskeleton; when... A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number; This represents the total number of sampling points; This is the time offset; It is a cross-correlation function; For the first Muscle vibration signals at the sampling points; for The vibration signal of the handle at a given time, where The sampling frequency; The method for determining the phase difference includes: Based on the second muscle vibration signal and the second handle vibration signal, determine the second amplitude ratio and the second time delay between the handle vibration signal and the muscle vibration signal; The second vibration interference signal is predicted based on the product of the second amplitude ratio, the second time delay, and the second handle vibration signal. The second pure muscle electrical signal is determined based on the difference between the second electromuscular signal and the second vibration interference signal. The time interval from the start of the task to the first time the second pure electromyographic signal exceeds the second activation threshold is taken as the muscle activation timing value; The difference between the muscle activation timing value and the muscle activation timing reference value is taken as the phase difference.

2. The phase calibration method for coordinating exoskeletons and construction tools according to claim 1, characterized in that, The muscle groups are determined based on the construction tools, work direction, and work tasks; The working direction includes an upward working direction, a downward working direction, or a horizontal working direction: when the angle between the working direction and the horizontal line is [-45, 45], it is a horizontal working direction; when the angle between the working direction and the horizontal line is [-90, -45), it is a downward working direction; when the angle between the working direction and the horizontal line is (45, 90], it is an upward working direction. The vibrating construction tool is configured to generate vibration during use and transmit it to the arm of the construction worker; The electrodes are used to collect raw muscle electrical signals from construction workers; The first sensor is used to collect muscle vibration signals from construction workers; The second sensor is used to collect vibration signals from the handle of the construction tool; The first signal set includes a first muscle electrical signal, a first muscle vibration signal, and a first handle vibration signal; The second signal set includes a second muscle electrical signal, a second muscle vibration signal, and a second handle vibration signal.

3. The phase calibration method for coordinating exoskeletons and construction tools according to claim 1, characterized in that, The methods for determining the start time of the operation include: The moment when the power supply current of the construction tool changes abruptly from zero to the working current is taken as the start time of the operation; Alternatively, the moment when the acceleration changes abruptly as detected by the second sensor can be taken as the start time of the operation.

4. The phase calibration method for coordinating exoskeletons and construction tools according to claim 1, characterized in that, The methods for determining the amplitude ratio include the following formulas: ； In the formula, The angle between the working direction and the horizontal line; The muscle number within the muscle group; The state of construction workers wearing exoskeletons, when A value of 0 indicates that the construction worker is not wearing an exoskeleton; when... A value of 1 indicates that the construction worker is wearing an exoskeleton; The amplitude ratio; This is the root mean square of the muscle vibration signal; This is the root mean square of the handle vibration signal.

5. The phase calibration method for coordinating exoskeletons and construction tools according to claim 1, characterized in that, Methods for predicting vibration interference signals include the following formulas: ； In the formula, when A value of 0 indicates that the construction worker is not wearing an exoskeleton. A value of 1 indicates that the construction worker is wearing an exoskeleton; The sampling point number; For time delay; for Vibration interference signal at the sampling time; The unit conversion factor represents the interference voltage generated in the electromuscular signal by vibration under unit gravitational acceleration; The amplitude ratio; for The vibration signal of the handle at any given moment.

6. The phase calibration method for coordinating exoskeletons and construction tools according to claim 5, characterized in that, The method for determining the unit conversion factor includes: Acquire the third electromyographic signal in the first time period, the fourth electromyographic signal in the second time period, and the fourth handle vibration signal; wherein, the first time period is from when the construction worker raises the construction tool and faces the construction surface to before the construction tool is powered on and started; the second time period is from when the construction tool leaves the construction surface and faces the construction surface to before the construction tool is powered off and turned off. Subtracting the third muscle electrical signal from the fourth muscle electrical signal yields the first difference; The unit conversion factor is determined based on the reciprocal of the amplitude ratio and the ratio of the first difference to the vibration signal of the fourth handle.

7. The phase calibration method for coordinating exoskeletons and construction tools according to claim 1, characterized in that, The method for correcting the triggering time of the exoskeleton assistive force includes: If the difference between the muscle activation timing value and the muscle activation timing baseline value is negative, it indicates that the intervention of the exoskeleton auxiliary force is delayed. In this case, the triggering time of the auxiliary force will be advanced, and the advance will be equal to the absolute value of the phase difference. If the difference between the muscle activation timing value and the muscle activation timing baseline value is positive, it indicates that the exoskeleton assist force intervention is ahead of schedule. In this case, the triggering time of the assist force will be delayed, and the delay will be equal to the absolute value of the phase difference.

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