CN113158459A - Human body posture estimation method based on visual and inertial information fusion - Google Patents

Human body posture estimation method based on visual and inertial information fusion Download PDF

Info

Publication number
CN113158459A
CN113158459A CN202110422431.7A CN202110422431A CN113158459A CN 113158459 A CN113158459 A CN 113158459A CN 202110422431 A CN202110422431 A CN 202110422431A CN 113158459 A CN113158459 A CN 113158459A
Authority
CN
China
Prior art keywords
coordinate system
human body
inertial
visual
skeleton
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110422431.7A
Other languages
Chinese (zh)
Inventor
张文安
朱腾辉
杨旭升
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University of Technology ZJUT
Original Assignee
Zhejiang University of Technology ZJUT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University of Technology ZJUT filed Critical Zhejiang University of Technology ZJUT
Priority to CN202110422431.7A priority Critical patent/CN113158459A/en
Publication of CN113158459A publication Critical patent/CN113158459A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F18/00Pattern recognition
    • G06F18/20Analysing
    • G06F18/23Clustering techniques
    • G06F18/232Non-hierarchical techniques
    • G06F18/2321Non-hierarchical techniques using statistics or function optimisation, e.g. modelling of probability density functions
    • G06F18/23213Non-hierarchical techniques using statistics or function optimisation, e.g. modelling of probability density functions with fixed number of clusters, e.g. K-means clustering
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06VIMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/20Movements or behaviour, e.g. gesture recognition
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2111/00Details relating to CAD techniques
    • G06F2111/04Constraint-based CAD

Landscapes

  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Data Mining & Analysis (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • General Engineering & Computer Science (AREA)
  • Evolutionary Computation (AREA)
  • Artificial Intelligence (AREA)
  • General Health & Medical Sciences (AREA)
  • Bioinformatics & Computational Biology (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Probability & Statistics with Applications (AREA)
  • Health & Medical Sciences (AREA)
  • Evolutionary Biology (AREA)
  • Psychiatry (AREA)
  • Social Psychology (AREA)
  • Human Computer Interaction (AREA)
  • Multimedia (AREA)
  • Computer Hardware Design (AREA)
  • Geometry (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Abstract

A human body posture estimation method based on visual and inertial information fusion aims at the defect that a human body posture estimation method based on a 3D visual sensor cannot provide three-degree-of-freedom rotation information, the visual information, the inertial information and human body posture prior information are fused in a self-adaptive mode by utilizing the complementarity of the visual information and the inertial information and adopting a nonlinear optimization method, the rotation angle of a human body skeleton node and the global position of a root skeleton node at each moment are obtained, and real-time human body posture estimation is completed. The invention effectively improves the accuracy and robustness of human body posture estimation, and makes up the defects that a visual sensor is easy to be shielded and inertial data accumulate errors along with time.

Description

Human body posture estimation method based on visual and inertial information fusion
Technical Field
The invention belongs to the field of human body posture estimation, and particularly relates to a human body posture estimation method based on visual and inertial information fusion.
Background
The human body posture estimation technology has important application value, and with the development of technologies such as a visual sensor, an inertial measurement unit, artificial intelligence and the like, the human body posture estimation technology is gradually applied to the fields of human-computer cooperation, video monitoring, movie and television production, industrial and agricultural production and the like, for example, the human body posture estimation technology is used for guaranteeing the safety problem of workers in the human-computer cooperation process, and is used for recording and analyzing the behavior of people in a monitoring picture and the like.
The 3D human body posture estimation technology is mature, and with the development of the fields of behavior recognition, auxiliary training, man-machine cooperation and the like, people need 6D human body posture estimation information to develop and apply, for example, in dance auxiliary training, the 6D human body posture estimation comprises joint rotation information, captured dance action details are richer, and trainees have better training effects. In daily production and life, the human body posture estimation method based on 3D vision is most common and practical, the method can be used for accurately extracting human body skeleton joint points to obtain 3D human body posture information, but when a human body is shielded by self or a camera is partially shielded, the data reliability is reduced. The inertial measurement unit may provide spatial rotation information whose output is stable, but the error in the rotation information accumulates over time. The human body can be subjected to 6D posture estimation by utilizing the complementarity of the visual information and the inertial information, the three-degree-of-freedom displacement information output by the visual information and the three-degree-of-freedom rotation information output by the inertial information are simply combined, and the obtained human body posture estimation system is poor in robustness and low in precision. At present, no technology exists for solving the 6D human body posture estimation problem by combining visual and inertial information in a robust and real-time manner.
Disclosure of Invention
In order to overcome the defect that a human body posture estimation method based on a 3D vision sensor cannot provide three-degree-of-freedom rotation information, the invention provides a human body posture estimation method based on vision and inertia information fusion.
The technical scheme adopted by the invention comprises the following steps:
a human body posture estimation method based on visual and inertial information fusion comprises the following steps:
step 1) establishing a kinematic model of each skeletal node of a human body, determining an optimized variable theta, and determining a homogeneous transformation matrix between a camera coordinate system c and a global coordinate system g
Figure BDA0003028378880000021
Rotation matrix between inertial coordinate system n and global coordinate system g
Figure BDA0003028378880000022
Inertial sensor i and corresponding bone coordinate system biA matrix of displacements between
Figure BDA0003028378880000023
And a rotation matrix
Figure BDA0003028378880000024
Step 2) setting the output frequency of vision and inertia to be consistent, and restricting the rotation of the inertial sensor by ER(theta), acceleration constraint EA(theta), visual sensor position constraint EP(theta) and body pose prior constraints Eprior(theta) constructing an optimization problem for the optimization items, and setting the weight of each optimization item;
step 3) reading the position measurement value of the vision sensor at each moment
Figure BDA0003028378880000025
And rotation measurement value R of inertial sensoriAnd acceleration measurement aiCalculating the sensor measurement value of each optimized item after the unified coordinate system
Figure BDA0003028378880000026
And the estimated value
Figure BDA0003028378880000027
Step 4) solving a nonlinear least square optimization problem, wherein the optimal solution theta at each moment is the optimal rotation angle of each skeleton node of the human body at the current momentDegree and root skeletal node n1Obtaining the estimation of the human body posture at the current moment according to the established human body skeleton node kinematics model;
and (5) repeatedly executing the steps 3) and 4) to complete the state estimation of each joint point of the human body at each moment, and obtaining the real-time human body posture estimation based on the fusion of visual and inertial information.
Further, in the step 1), the camera coordinate system c represents a coordinate system of the depth camera, the inertial coordinate system n represents a unified coordinate system of all the inertial sensors after calibration, and the global coordinate system g is aligned with the initial coordinate system of the bone node.
In the step 2), the rotation is restrictedR(θ) established by the difference between the measured and estimated values of each IMU rotation matrix; the acceleration constraint EA(θ) established by minimizing a difference between the measured and estimated values of acceleration of each IMU; the position constraint EP(θ) established by minimizing the difference between the measured and estimated values of the global position of each bone node; the human body posture prior constraint Eprior(θ) is established by the existing body pose estimation dataset.
In the step 3), the
Figure BDA0003028378880000031
Is the position information of each joint point of the human body, R, read from a vision sensoriIs the rotation information read from an inertial gyroscope, aiIs the acceleration information read from an inertial accelerometer.
In the step 4), the root skeleton node n1Is positioned at the pelvic joint point of the human body.
The invention has the following beneficial effects: aiming at the defect that the human body posture estimation method based on the 3D visual sensor lacks three-degree-of-freedom rotation information output, the human body posture estimation method based on the visual and inertial information fusion adopts a nonlinear optimization method to adaptively fuse the visual information, the inertial information and the human body posture prior information to obtain 6D human body posture estimation, improves the precision and the robustness of the human body posture estimation, and makes up the defects that the visual sensor is easy to be shielded and the inertial data accumulates errors along with time.
Drawings
FIG. 1 is a flow chart of a human body posture estimation method based on visual and inertial information fusion.
Fig. 2 is a schematic view of a position where an upper body bone node and an IMU are worn on a human body.
Fig. 3 is a schematic view of the placement of the visual sensors.
FIG. 4 is a flow chart of a human body posture estimation algorithm with fusion of visual and inertial information.
Detailed Description
In order to make the technical scheme and the design idea of the invention clearer, the posture estimation object selects the upper half of the human body, two visual sensors and five inertial sensors are adopted, and the invention is further described by combining the attached drawings.
Referring to fig. 1,2,3 and 4, a human body posture estimation method based on fusion of visual and inertial information includes the following steps:
step 1) establishing a kinematic model of each skeletal node of a human body, determining an optimized variable theta, and determining a homogeneous transformation matrix between a camera coordinate system c and a global coordinate system g
Figure BDA0003028378880000041
Rotation matrix between inertial coordinate system n and global coordinate system g
Figure BDA0003028378880000042
Inertial sensor i and corresponding bone coordinate system biA matrix of displacements between
Figure BDA0003028378880000043
And a rotation matrix
Figure BDA0003028378880000044
The process is as follows:
1.1) human skeleton is defined as interconnected rigid bodies, the initial coordinate system B of the skeleton nodes and the globalThe coordinate system g is aligned, defining the upper half skeleton number nb13, as shown in fig. 2, the bone nodes are the left hand, right hand, left forearm, right forearm, left upper arm, right upper arm, left shoulder, right shoulder, spine 1-4, and pelvis, respectively, wherein the pelvis is considered as root bone node n1Sub-skeleton node nb(b ≧ 2) rotation matrices R all having a relative relation to its parent nodebAnd a relatively constant displacement tbEach bone has 3 rotational degrees of freedom, and the root node has a global displacement (x)1,y1,z1) By 42(d ═ 3+3 xn)b42) freedom degrees to express the motion of the whole upper body of the human body, 42 variables are recorded as a 42-dimensional vector theta which is used as an optimization variable of an optimization problem, and a homogeneous transformation matrix of each rigid skeleton under a global coordinate system is obtained by derivation through a forward kinematics formula
Figure BDA0003028378880000045
Figure BDA0003028378880000051
Wherein p (b) is the set of total bones;
1.2) as shown in fig. 3, two vision sensors are respectively placed in front of a tester, the vision sensors are 2 meters away from the tester L, and a translation matrix of the two cameras to a global coordinate system g is obtained by using a Zhang Yong camera calibration method
Figure BDA0003028378880000052
And a rotation matrix
Figure BDA0003028378880000053
Further determining homogeneous transformation matrix of camera coordinate system c and global coordinate system g
Figure BDA0003028378880000054
1.3) placing the inertial sensor IMU at the global coordinate system g such that the inertial sensor coordinate system n is aligned with the global coordinate system gObtaining the output value of the inertial sensor at the moment, namely the rotation matrix between the coordinate system n of the inertial sensor and the global coordinate system g
Figure BDA0003028378880000055
Repeating the above operations to obtain the i (i is 1,2,3,4,5) th inertial sensor coordinate system niA rotation matrix with the global coordinate system g
Figure BDA0003028378880000056
1.4) the IMU is worn at the corresponding skeletal points of the left hand, right hand, left forearm, right forearm, pelvic bone, as shown in FIG. 2iWith a corresponding skeleton coordinate system biThere is no displacement therebetween, i.e.
Figure BDA0003028378880000057
At an initial time the tester makes a "T-pos" calibration pose, at which time the IMU is definediMeasured value of (A) is Ri_initialThen IMUiWith a corresponding skeleton coordinate system biA rotation matrix of
Figure BDA0003028378880000058
Expressed as:
Figure BDA0003028378880000059
step 2) setting the output frequency of vision and inertia to be 30HZ, and restricting the rotation of the inertial sensor to be ER(theta), acceleration constraint EA(theta), visual sensor position constraint EP(theta) and body pose prior constraints Eprior(theta) constructing an optimization problem for the optimization items, and setting the weight of each optimization item; the process is as follows:
2.1)IMUithe difference between the measured and estimated values of the rotation matrix of the corresponding bone node in the global coordinate system serves as the rotation term constraint of the IMU. The rotation matrix measurements for the corresponding bone nodes are expressed as:
Figure BDA0003028378880000061
wherein R isiIs an IMUiIs measured. The rotation matrix estimate values for the corresponding bone nodes are expressed as:
Figure BDA0003028378880000062
wherein, P (b)i) Is a skeleton biA collection of all parents.
In summary, the energy function of the rotation term is defined as:
Figure BDA0003028378880000063
wherein ψ (-) extracts the vector part, λ, of the rotation matrix quaternion expression methodRWeight of the energy function of the rotation term, pR(. cndot.) represents a loss function.
2.2) minimizing IMUiAcceleration measurement aiAnd the error between the estimated value is used as an acceleration constraint term of the IMU. Acceleration estimation value
Figure BDA0003028378880000064
Expressed as:
Figure BDA0003028378880000065
wherein,
Figure BDA0003028378880000066
the left side (t-1) of equation (6) indicates that the acceleration constraint for the previous time instant is used at the current time instant. Acceleration measurements in a global coordinate system
Figure BDA0003028378880000067
And calculating the rotation information and the acceleration measured value of the previous frame. Acceleration measurementValue of
Figure BDA0003028378880000068
Expressed as:
Figure BDA0003028378880000069
wherein, agIs the acceleration of gravity.
In summary, the energy function of the acceleration term is defined as:
Figure BDA00030283788800000610
wherein λ isAWeight of the energy function of the acceleration term, pA(. cndot.) represents a loss function.
2.3) obtaining the global coordinates (x, y, z) of the human skeleton nodes from the depth camera of the vision sensor, and adding a constraint term which minimizes the minimization between the measured value and the estimated value of the global position of the skeleton nodes. Defining the number of skeletal nodes for the location constraint term as npThe position of the skeleton node in the c coordinate system of the camera is
Figure BDA0003028378880000071
The number of cameras is nc. Estimation of bone node position
Figure BDA0003028378880000072
Expressed as:
Figure BDA0003028378880000073
in summary, the energy function of the position constraint is defined as:
Figure BDA0003028378880000074
wherein λ isPConstraining the term energy for positionWeight of the function, pP(. cndot.) represents a loss function.
2.4) there is a limit to consider the freedom of motion of the actual skeleton, so the attitude prior term E is usedprior(θ) to limit the unreasonable movement of the joint. Eprior(θ) is established by the existing human body posture estimation data set "TotalCapture (2017)" which contains 126000 frames of human body motion posture data.
First, k-means clustering is performed on all data in a data set, and a cluster type k is selected as 126000/100 as 1260. And then taking the mean value of all the clustering centers to obtain the mean value mu of the postures. Finally, carrying out statistical analysis on the original data to obtain the standard deviation sigma of the posture and the upper and lower limits theta of the freedom degree of each bone nodemaxAnd thetamin. Thus, the attitude prior term is defined as:
Figure BDA0003028378880000075
wherein,
Figure BDA0003028378880000076
has a dimension of 36, does not limit the displacement and rotation of the root node, lambdapriorWeight of the energy function of the attitude prior term, pprior(. cndot.) represents a loss function.
2.5) in summary, an optimization problem is constructed:
Figure BDA0003028378880000081
wherein E isA、EP、EpriorThe loss function in (1) is set to ρ (x) log (1+ x), and the influence of the abnormal value is limited by increasing the penalty to the abnormal value in a set proportion. The weight of each optimization term is set to be lambdaR=0.1,λP=10,λA=0.005,λprior=0.0001。
Step 3) reading the position measurement values of the vision sensor at each moment
Figure BDA0003028378880000082
And rotation measurement value R of inertial sensoriAnd acceleration measurement aiCalculating the sensor measurement value of each optimized item after the unified coordinate system
Figure BDA0003028378880000083
And the estimated value
Figure BDA0003028378880000084
Step 4) solving a nonlinear least square optimization problem, wherein the optimal solution theta at each moment is the optimal rotation angle of each skeleton node of the human body at the current moment and a root skeleton node n1Obtaining the estimation of the human body posture at the current moment according to the established human body skeleton node kinematics model;
as shown in fig. 1, the steps 3) and 4) are repeatedly executed to finish the optimal estimation of the position and the rotation of the human joint point at each moment, so as to obtain the real-time human posture estimation based on the fusion of visual and inertial information.
The embodiments described in this specification are merely illustrative of implementations of the inventive concepts, which are intended for purposes of illustration only. The scope of the present invention should not be construed as being limited to the particular forms set forth in the examples, but rather as being defined by the claims and the equivalents thereof which can occur to those skilled in the art upon consideration of the present inventive concept.

Claims (7)

1. A human body posture estimation method based on visual and inertial information fusion is characterized by comprising the following steps:
step 1) establishing a kinematic model of each skeletal node of a human body, determining an optimized variable theta, and determining a homogeneous transformation matrix between a camera coordinate system c and a global coordinate system g
Figure FDA0003028378870000011
Rotation matrix between inertial coordinate system n and global coordinate system g
Figure FDA0003028378870000012
Inertial sensor i and corresponding bone coordinate system biA matrix of displacements between
Figure FDA0003028378870000013
And a rotation matrix
Figure FDA0003028378870000014
Step 2) setting the output frequency of vision and inertia to be consistent, and restricting the rotation of the inertial sensor by ER(theta), acceleration constraint EA(theta), visual sensor position constraint EP(theta) and body pose prior constraints Eprior(theta) constructing an optimization problem for the optimization items, and setting the weight of each optimization item;
step 3) reading the position measurement value of the vision sensor at each moment
Figure FDA0003028378870000015
And rotation measurement value R of inertial sensoriAnd acceleration measurement aiCalculating the sensor measurement value of each optimized item after the unified coordinate system
Figure FDA0003028378870000016
And the estimated value
Figure FDA0003028378870000017
Step 4) solving the nonlinear least square optimization problem to obtain the optimal solution theta at each moment, namely the optimal rotation angle of each skeleton node of the human body at the current moment and the root skeleton node n1Obtaining the estimation of the human body posture at the current moment according to the established human body skeleton node kinematics model;
and 5) repeatedly executing the steps 3) and 4) to complete the state estimation of each joint point of the human body at each moment, so as to obtain the real-time human body posture estimation based on the fusion of visual and inertial information.
2. The human body posture estimation method based on the fusion of visual and inertial information as claimed in claim 1, wherein in the step 1), the camera coordinate system c represents the coordinate system of the depth camera, the inertial coordinate system n represents the calibrated unified coordinate system of all the inertial sensors, and the global coordinate system g is aligned with the initial coordinate system of the bone node.
3. The human body posture estimation method based on the fusion of visual and inertial information according to claim 1 or 2, characterized in that in the step 2), the rotation constraint E isR(θ) established by the difference between the measured and estimated values of each IMU rotation matrix; the acceleration constraint EA(θ) established by minimizing a difference between the measured and estimated values of acceleration of each IMU; the position constraint EP(θ) established by minimizing the difference between the measured and estimated values of the global position of each bone node; the human body posture prior constraint Eprior(θ) is established by the existing body pose estimation dataset.
4. The human body posture estimation method based on the fusion of visual and inertial information as claimed in claim 1 or 2, characterized in that in the step 3), the human body posture estimation method
Figure FDA0003028378870000021
Is the position information of each joint point of the human body, R, read from a vision sensoriIs the rotation information read from an inertial gyroscope, aiIs the acceleration information read from an inertial accelerometer.
5. The human body posture estimation method based on visual and inertial information fusion of claim 1 or 2, characterized in that in the step 4), the root skeleton node n1Is positioned at the pelvic joint point of the human body.
6. The human body posture estimation method based on the fusion of the visual information and the inertial information as claimed in claim 1 or 2, characterized in that the process of the step 1) is:
1.1) human skeleton is defined as interconnected rigid bodies, the initial coordinate system B of the skeleton node is aligned with the global coordinate system g, and the number n of upper semi-body skeleton is definedb13, the bone nodes are respectively the left hand, the right hand, the left forearm, the right forearm, the left upper arm, the right upper arm, the left shoulder, the right shoulder, the spine 1-4 and the pelvis, wherein the pelvis is taken as a root bone node n1Sub-skeleton node nb(b ≧ 2) rotation matrices R all having a relative relation to its parent nodebAnd a relatively constant displacement tbEach bone has 3 rotational degrees of freedom, and the root node has a global displacement (x)1,y1,z1) By 42(d ═ 3+3 xn)b42) freedom degrees to express the motion of the whole upper body of the human body, 42 variables are recorded as a 42-dimensional vector theta which is used as an optimization variable of an optimization problem, and a homogeneous transformation matrix of each rigid skeleton under a global coordinate system is obtained by derivation through a forward kinematics formula
Figure FDA0003028378870000031
Figure FDA0003028378870000032
Wherein p (b) is the set of total bones;
1.2) respectively placing two visual sensors in front of a tester, wherein the distance between the visual sensors and the tester L is 2 meters, and obtaining translation matrixes of the two cameras to a global coordinate system g by using a Zhang Yong camera calibration method
Figure FDA0003028378870000033
And a rotation matrix
Figure FDA0003028378870000034
Further determining homogeneous transformation matrix of camera coordinate system c and global coordinate system g
Figure FDA0003028378870000035
1.3) placing the inertial sensor IMU at the global coordinate system g to align the inertial sensor coordinate system n with the global coordinate system g to obtain the output value of the inertial sensor, namely the rotation matrix between the inertial sensor coordinate system n and the global coordinate system g
Figure FDA0003028378870000036
Repeating the above operations to obtain the i (i is 1,2,3,4,5) th inertial sensor coordinate system niA rotation matrix with the global coordinate system g
Figure FDA0003028378870000037
1.4) the IMU is worn on the corresponding skeletal points of the left hand, right hand, left forearm, right forearm, pelvic boneiWith a corresponding skeleton coordinate system biThere is no displacement therebetween, i.e.
Figure FDA0003028378870000038
At an initial time the tester makes a "T-pos" calibration pose, at which time the IMU is definediMeasured value of (A) is Ri_initialThen IMUiWith a corresponding skeleton coordinate system biA rotation matrix of
Figure FDA0003028378870000039
Expressed as:
Figure FDA00030283788700000310
7. the human body posture estimation method based on the fusion of the visual information and the inertial information as claimed in claim 6, wherein the process of the step 2) is as follows:
2.1)IMUicorresponding bone nodes are allThe difference between the measured value and the estimated value of the rotation matrix in the local coordinate system is used as the rotation term constraint of the IMU, and the measured value of the rotation matrix corresponding to the bone node is expressed as:
Figure FDA0003028378870000041
wherein R isiIs an IMUiThe estimated value of the rotation matrix corresponding to the bone node is expressed as:
Figure FDA0003028378870000042
wherein, P (b)i) Is a skeleton biA set of all parents;
in summary, the energy function of the rotation term is defined as:
Figure FDA0003028378870000043
wherein ψ (-) extracts the vector part, λ, of the rotation matrix quaternion expression methodRWeight of the energy function of the rotation term, pR(. represents a loss function;
2.2) minimizing IMUiAcceleration measurement aiAnd the error between the estimated value and the acceleration estimated value is used as an acceleration constraint term of the IMU
Figure FDA0003028378870000044
Expressed as:
Figure FDA0003028378870000045
wherein,
Figure FDA0003028378870000046
left side of equation (6)(t-1) represents the acceleration measurements in the global coordinate system using the acceleration constraints of the previous time at the current time
Figure FDA0003028378870000047
Calculated from the rotation information and the measured acceleration value of the previous frame
Figure FDA0003028378870000048
Expressed as:
Figure FDA0003028378870000049
wherein, agIs the acceleration of gravity;
in summary, the energy function of the acceleration term is defined as:
Figure FDA00030283788700000410
wherein λ isAWeight of the energy function of the acceleration term, pA(. represents a loss function;
2.3) obtaining global coordinates (x, y, z) of human skeleton nodes from a depth camera of a visual sensor, adding a constraint term minimizing minimization between a measured value and an estimated value of the global position of the skeleton nodes, and defining the number of skeleton nodes for the position constraint term as npThe position of the skeleton node in the c coordinate system of the camera is
Figure FDA0003028378870000051
The number of cameras is ncEstimation of bone node position
Figure FDA0003028378870000052
Expressed as:
Figure FDA0003028378870000053
in summary, the energy function of the position constraint is defined as:
Figure FDA0003028378870000054
wherein λ isPWeight of the energy function of the position constraint term, pP(. represents a loss function;
2.4) there is a limit to consider the freedom of motion of the actual skeleton, so the attitude prior term E is usedprior(theta) to limit unwanted movement of the joint, Eprior(theta) is established by an existing human body posture estimation data set 'TotalCapture (2017)', wherein 126000 frames of human body motion posture data are contained;
firstly, carrying out k-means clustering on all data in a data set, selecting a clustering type k which is 126000/100 which is 1260, then, taking a mean value of all clustering centers to obtain a mean value mu of a posture, and finally, carrying out statistical analysis on original data to obtain a standard deviation sigma of the posture and upper and lower freedom degree limits theta of each bone nodemaxAnd thetaminThus, the attitude prior term is defined as:
Figure FDA0003028378870000055
wherein,
Figure FDA0003028378870000056
has a dimension of 36, does not limit the displacement and rotation of the root node, lambdapriorWeight of the energy function of the attitude prior term, pprior(. represents a loss function;
2.5) in summary, an optimization problem is constructed:
Figure FDA0003028378870000061
wherein E isA、EP、EpriorThe loss function in (1) is set as rho (x) log (1+ x), the influence of the abnormal value is limited by increasing the punishment to the abnormal value according to the set proportion, and the weight of each optimization term is set as lambdaR=0.1,λP=10,λA=0.005,λprior=0.0001。
CN202110422431.7A 2021-04-20 2021-04-20 Human body posture estimation method based on visual and inertial information fusion Pending CN113158459A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110422431.7A CN113158459A (en) 2021-04-20 2021-04-20 Human body posture estimation method based on visual and inertial information fusion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110422431.7A CN113158459A (en) 2021-04-20 2021-04-20 Human body posture estimation method based on visual and inertial information fusion

Publications (1)

Publication Number Publication Date
CN113158459A true CN113158459A (en) 2021-07-23

Family

ID=76868924

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110422431.7A Pending CN113158459A (en) 2021-04-20 2021-04-20 Human body posture estimation method based on visual and inertial information fusion

Country Status (1)

Country Link
CN (1) CN113158459A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114332912A (en) * 2021-11-22 2022-04-12 清华大学 Human motion capture and joint stress analysis method based on IMU
CN114396936A (en) * 2022-01-12 2022-04-26 上海交通大学 Method and system for estimating attitude of inertia and magnetic sensor based on polynomial optimization
CN114627490A (en) * 2021-12-15 2022-06-14 浙江工商大学 Multi-person attitude estimation method based on inertial sensor and multifunctional camera
CN114742889A (en) * 2022-03-16 2022-07-12 北京工业大学 Human body dance action detection and correction method based on nine-axis attitude sensor and machine vision
CN116912948A (en) * 2023-09-12 2023-10-20 南京硅基智能科技有限公司 Training method, system and driving system for digital person
US11809616B1 (en) 2022-06-23 2023-11-07 Qing Zhang Twin pose detection method and system based on interactive indirect inference

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102435188A (en) * 2011-09-15 2012-05-02 南京航空航天大学 Monocular vision/inertia autonomous navigation method for indoor environment
CN104501814A (en) * 2014-12-12 2015-04-08 浙江大学 Attitude and position estimation method based on vision and inertia information
CN106052584A (en) * 2016-05-24 2016-10-26 上海工程技术大学 Track space linear shape measurement method based on visual and inertia information fusion
CN107687850A (en) * 2017-07-26 2018-02-13 哈尔滨工业大学深圳研究生院 A kind of unmanned vehicle position and orientation estimation method of view-based access control model and Inertial Measurement Unit
CN108731672A (en) * 2018-05-30 2018-11-02 中国矿业大学 Coalcutter attitude detection system and method based on binocular vision and inertial navigation
CN110100151A (en) * 2017-01-04 2019-08-06 高通股份有限公司 The system and method for global positioning system speed is used in vision inertia ranging
CN110327048A (en) * 2019-03-11 2019-10-15 浙江工业大学 A kind of human upper limb posture reconstruction system based on wearable inertial sensor
CN110345944A (en) * 2019-05-27 2019-10-18 浙江工业大学 Merge the robot localization method of visual signature and IMU information
CN110375738A (en) * 2019-06-21 2019-10-25 西安电子科技大学 A kind of monocular merging Inertial Measurement Unit is synchronous to be positioned and builds figure pose calculation method
CN110530365A (en) * 2019-08-05 2019-12-03 浙江工业大学 A kind of estimation method of human posture based on adaptive Kalman filter
CN110617814A (en) * 2019-09-26 2019-12-27 中国科学院电子学研究所 Monocular vision and inertial sensor integrated remote distance measuring system and method
CN111222437A (en) * 2019-12-31 2020-06-02 浙江工业大学 Human body posture estimation method based on multi-depth image feature fusion
CN111241936A (en) * 2019-12-31 2020-06-05 浙江工业大学 Human body posture estimation method based on depth and color image feature fusion
CN111578937A (en) * 2020-05-29 2020-08-25 天津工业大学 Visual inertial odometer system capable of optimizing external parameters simultaneously
CN111595333A (en) * 2020-04-26 2020-08-28 武汉理工大学 Modularized unmanned vehicle positioning method and system based on visual inertial laser data fusion

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102435188A (en) * 2011-09-15 2012-05-02 南京航空航天大学 Monocular vision/inertia autonomous navigation method for indoor environment
CN104501814A (en) * 2014-12-12 2015-04-08 浙江大学 Attitude and position estimation method based on vision and inertia information
CN106052584A (en) * 2016-05-24 2016-10-26 上海工程技术大学 Track space linear shape measurement method based on visual and inertia information fusion
CN110100151A (en) * 2017-01-04 2019-08-06 高通股份有限公司 The system and method for global positioning system speed is used in vision inertia ranging
CN107687850A (en) * 2017-07-26 2018-02-13 哈尔滨工业大学深圳研究生院 A kind of unmanned vehicle position and orientation estimation method of view-based access control model and Inertial Measurement Unit
CN108731672A (en) * 2018-05-30 2018-11-02 中国矿业大学 Coalcutter attitude detection system and method based on binocular vision and inertial navigation
CN110327048A (en) * 2019-03-11 2019-10-15 浙江工业大学 A kind of human upper limb posture reconstruction system based on wearable inertial sensor
CN110345944A (en) * 2019-05-27 2019-10-18 浙江工业大学 Merge the robot localization method of visual signature and IMU information
CN110375738A (en) * 2019-06-21 2019-10-25 西安电子科技大学 A kind of monocular merging Inertial Measurement Unit is synchronous to be positioned and builds figure pose calculation method
CN110530365A (en) * 2019-08-05 2019-12-03 浙江工业大学 A kind of estimation method of human posture based on adaptive Kalman filter
CN110617814A (en) * 2019-09-26 2019-12-27 中国科学院电子学研究所 Monocular vision and inertial sensor integrated remote distance measuring system and method
CN111222437A (en) * 2019-12-31 2020-06-02 浙江工业大学 Human body posture estimation method based on multi-depth image feature fusion
CN111241936A (en) * 2019-12-31 2020-06-05 浙江工业大学 Human body posture estimation method based on depth and color image feature fusion
CN111595333A (en) * 2020-04-26 2020-08-28 武汉理工大学 Modularized unmanned vehicle positioning method and system based on visual inertial laser data fusion
CN111578937A (en) * 2020-05-29 2020-08-25 天津工业大学 Visual inertial odometer system capable of optimizing external parameters simultaneously

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114332912A (en) * 2021-11-22 2022-04-12 清华大学 Human motion capture and joint stress analysis method based on IMU
CN114627490A (en) * 2021-12-15 2022-06-14 浙江工商大学 Multi-person attitude estimation method based on inertial sensor and multifunctional camera
CN114627490B (en) * 2021-12-15 2024-10-18 浙江工商大学 Multi-person gesture estimation method based on inertial sensor and multifunctional camera
CN114396936A (en) * 2022-01-12 2022-04-26 上海交通大学 Method and system for estimating attitude of inertia and magnetic sensor based on polynomial optimization
CN114396936B (en) * 2022-01-12 2024-03-12 上海交通大学 Polynomial optimization-based inertial and magnetic sensor attitude estimation method and system
CN114742889A (en) * 2022-03-16 2022-07-12 北京工业大学 Human body dance action detection and correction method based on nine-axis attitude sensor and machine vision
US11809616B1 (en) 2022-06-23 2023-11-07 Qing Zhang Twin pose detection method and system based on interactive indirect inference
CN116912948A (en) * 2023-09-12 2023-10-20 南京硅基智能科技有限公司 Training method, system and driving system for digital person
CN116912948B (en) * 2023-09-12 2023-12-01 南京硅基智能科技有限公司 Training method, system and driving system for digital person

Similar Documents

Publication Publication Date Title
CN113158459A (en) Human body posture estimation method based on visual and inertial information fusion
CN110530365B (en) Human body attitude estimation method based on adaptive Kalman filtering
CN105856230B (en) A kind of ORB key frames closed loop detection SLAM methods for improving robot pose uniformity
CN107516326B (en) Robot positioning method and system fusing monocular vision and encoder information
CN111595333A (en) Modularized unmanned vehicle positioning method and system based on visual inertial laser data fusion
CN103733227B (en) Three-dimensional object modelling fitting & tracking
CN111156984A (en) Monocular vision inertia SLAM method oriented to dynamic scene
CN112556719B (en) Visual inertial odometer implementation method based on CNN-EKF
JP6145072B2 (en) Sensor module position acquisition method and apparatus, and motion measurement method and apparatus
CN112401369B (en) Body parameter measurement method, system, device, chip and medium based on human body reconstruction
CN116205947A (en) Binocular-inertial fusion pose estimation method based on camera motion state, electronic equipment and storage medium
CN111489392B (en) Single target human motion posture capturing method and system in multi-person environment
CN110609621B (en) Gesture calibration method and human motion capture system based on microsensor
CN112750198A (en) Dense correspondence prediction method based on non-rigid point cloud
Zhang et al. Human motion capture based on kinect and imus and its application to human-robot collaboration
CN108900775B (en) Real-time electronic image stabilization method for underwater robot
CN114485637A (en) Visual and inertial mixed pose tracking method of head-mounted augmented reality system
CN112131928A (en) Human body posture real-time estimation method based on RGB-D image feature fusion
CN115661862A (en) Pressure vision convolution model-based sitting posture sample set automatic labeling method
CN109931940B (en) Robot positioning position reliability assessment method based on monocular vision
CN111241936A (en) Human body posture estimation method based on depth and color image feature fusion
Henning et al. Bodyslam++: Fast and tightly-coupled visual-inertial camera and human motion tracking
CN113256789A (en) Three-dimensional real-time human body posture reconstruction method
CN111222437A (en) Human body posture estimation method based on multi-depth image feature fusion
JP6205387B2 (en) Method and apparatus for acquiring position information of virtual marker, and operation measurement method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination