Kinematics analysis method of flexible solar wing scissor-type unfolding mechanism

Abstract

The invention discloses a kinematics analysis method of a flexible solar wing shear fork type unfolding mechanism in the technical field of solar wing unfolding mechanisms, which comprises the following steps of: S1, determining the angles and the angular velocities of a rod 2 and a rod 3 by using the angle and the angular velocity of a rod 1 of a driving link as theta and # imgabs0 #, analyzing a planar four-rod mechanism by using a closed vector polygon, and listing an equation by using a vector of the planar four-rod mechanism; according to the kinematics analysis method of the flexible solar wing shear-fork type unfolding mechanism, the kinematics of the shear-fork type unfolding mechanism is analyzed, the kinematics characteristics of the shear-fork type unfolding mechanism are researched, the unfolding stability of a flexible solar wing is ensured, and the phenomena of impact and stagnation existing in the unfolding process of the unfolding mechanism are avoided; when kinematics analysis is carried out, static analysis is also carried out on the mechanism, the kinematics analysis is used as a basis for follow-up motor model selection, the driving torque needing to be provided at the position of the rod 1 can be conveniently calculated, the torque requirement is met, meanwhile, a certain safety margin is reserved, and the stability of the flexible solar wing shear fork type unfolding mechanism is further guaranteed.

Description

Technical Field

[0001] The invention discloses a kinematic analysis method for a flexible solar wing scissor-type unfolding mechanism, and specifically relates to the technical field of solar wing unfolding mechanisms. Background Art

[0002] Solar wings are the main source of energy for satellites. Depending on the substrate that carries the battery cells, solar wings are divided into rigid, semi-rigid and flexible solar wings. Traditional rigid solar wings have relatively thick substrates and a large gap between the boards, resulting in a relatively large overall "block", which takes up a lot of the spacecraft's envelope. Semi-rigid solar wings are similar. Flexible solar wings generally use a flexible film structure less than 1 mm thick as a substrate. After folding, different substrates are completely in contact and pressed. They have the characteristics of small envelope requirements, strong designability, and easy expansion. They are generally considered to be an important form of next-generation satellite energy. Flexible solar wings have the characteristics of small envelope, light weight, and modularity. They can perfectly meet the envelope requirements of flat-panel satellite layered stacking, making large-scale satellite stacking launch possible.

[0003] The scissors-type deployment mechanism is one of the accessories used in conjunction with the flexible solar wing. It is designed to help unfold the flexible solar wing. Its main body is a number of scissors rods, the roots of which are connected to the bottom frame, and the tops are connected to the top frame. At the same time, the top frame is also connected to the top plate. When the mechanism is folded, it compresses and protects the flexible solar wing in the folded state. The flexible solar wing is usually stored in an accordion-like folding manner.

[0004] However, during the deployment of the flexible solar wing, the wing scissor-type deployment mechanism will have poor stability due to the lack of kinematic analysis. There will be impact and stagnation during the deployment of the wing scissor-type deployment mechanism. In addition, in the statics analysis that is closely related to the kinematic analysis, there is a lack of basis for subsequent motor selection. It is difficult to understand the driving torque that needs to be provided and it is difficult to meet the torque requirements, which further reduces the stability of the flexible solar wing scissor-type deployment mechanism. Summary of the invention

[0005] The object of the present invention is to provide a kinematic analysis method for a flexible solar wing scissor-type deployment mechanism, so as to solve the problem raised in the above background technology that during the deployment of the flexible solar wing, the wing scissor-type deployment mechanism will have poor stability in the absence of kinematic analysis, and there will be impact and stagnation during the deployment of the wing scissor-type deployment mechanism. In addition, in the statics analysis closely related to the kinematic analysis, there is a lack of basis for subsequent motor selection, and it is difficult to understand the driving torque that needs to be provided and to meet the torque requirements, which further reduces the stability of the flexible solar wing scissor-type deployment mechanism.

[0006] To achieve the above object, the present invention provides the following technical solution: comprising the following steps:

[0007] S1: The angle and angular velocity of the prime mover rod 1 are θ and Determine the angle and angular velocity of rod 2 and rod 3. The planar four-bar mechanism is analyzed using a closed vector polygon and the equation is written using its vector column:

[0008]

[0009] θ i Separating the real and imaginary parts by measuring counterclockwise from the positive x-axis gives:

[0010]

[0011] This equation can be used to solve the unknown azimuth angle θ 2 ,θ 3 Solving for θ 3 When the left side of the two fractions contains θ 1 Move the term to the right, square both ends and add them together, let:

[0012]

[0013] The solution is:

[0014]

[0015] Substituting the boundary conditions, when θ 1 =90°, θ 3 =-90°, we can conclude that the sign in should be positive, and we can find θ 3 Then, find θ 2 :

[0016]

[0017] Taking the derivative with respect to time, we get:

[0018]

[0019] That is The complex form of , separating the real and imaginary parts:

[0020]

[0021] The two unknown angular velocities can be solved and

[0022]

[0023] S2: After analyzing the four-bar mechanism, we will analyze the kinematics of the entire mechanism. Due to the characteristics of the four-bar mechanism, the entire mechanism will have lateral displacement during the deployment process. The size of the lateral displacement needs to be calculated to evaluate the impact on the flexible solar wing. The length of each bar is:

[0024]

[0025] The θ obtained by the formula 1 With θ 3 , calculate the angles θ and a between rod 1 and rod 3 and the horizontal axis respectively, draw the graph, and the maximum angle difference max(θ-α)=6.8539°;

[0026] S3: Next, calculate the lateral displacement of the mechanism during the deployment process caused by the angle difference:

[0027] First calculate the δ angle in the figure:

[0028]

[0029] Distance of DE:

[0030] DE=0.6cosy+0.6cosβ+0.6cosδ (3-14)

[0031] Then the lateral distance of the mechanism is:

[0032]

[0033] Plot the lateral displacement w versus the drive angle θ, and its maximum value w max = 0.2377m, obtained when θ = 60.3°;

[0034] S4: Next, the relationship between the deployment height h of the mechanism and the drive angle θ is calculated:

[0035]

[0036] Plot h vs. θ. When fully expanded, h max =6.2912m;

[0037] S5: The kinematic analysis method of the above-mentioned flexible solar wing scissor-type deployment mechanism also includes a static analysis of the deployment process.

[0038] Preferably, in the static analysis, the driving torque of the rod 1 is M, and the top of the mechanism is subjected to a tension load Q from a constant force spring. According to the principle of virtual work:

[0039]

[0040] The relationship between h and θ is determined by (2-14), and the difference method is used to find the approximate Draw the image.

[0041] Preferably, for the top load Q, the required driving torque M decreases as θ increases. At the end of the deployment, when θ=85°, the top load Q=17.64N is applied. At this time, the required driving torque M is 17 .64×2.0334= 35 .8692Nm.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] 1. The kinematic analysis method of the scissor-type deployment mechanism of the flexible solar wing is used to analyze the kinematics of the scissor-type deployment mechanism and study its kinematic characteristics to ensure the smooth deployment of the flexible solar wing and avoid impact and stagnation of the deployment mechanism during the deployment process.

[0044] 2. The kinematic analysis method of the flexible solar wing scissor-type deployment mechanism is to conduct a static analysis of the mechanism while conducting the kinematic analysis, which serves as the basis for the subsequent motor selection, so as to calculate the driving torque required at rod 1 to meet the torque requirements while leaving a certain safety margin to further ensure the stability of the flexible solar wing scissor-type deployment mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic diagram of the kinematic analysis of a planar four-bar mechanism of the kinematic analysis method of the flexible solar wing scissor-type deployment mechanism of the present invention;

[0046] Figure 2 A kinematic schematic diagram of a scissor-type deployment mechanism of a flexible solar wing scissor-type deployment mechanism according to the present invention;

[0047] Figure 3 A schematic diagram of the angle difference of a four-bar mechanism of a kinematic analysis method of a scissor-type deployment mechanism of a flexible solar wing according to the present invention;

[0048] Figure 4 A schematic diagram of a four-bar mechanism and a scissor bar for a kinematic analysis method of a flexible solar wing scissor-type deployment mechanism of the present invention;

[0049] Figure 5 It is a schematic diagram of the lateral displacement of the kinematic analysis method of the flexible solar wing scissor-type deployment mechanism of the present invention;

[0050] Figure 6 It is a schematic diagram of the deployment height of the kinematic analysis method of the flexible solar wing scissor-type deployment mechanism of the present invention;

[0051] Figure 7It is a simplified schematic diagram of the static analysis of the scissor mechanism of the kinematic analysis method of the flexible solar wing scissor-type deployment mechanism of the present invention;

[0052] Figure 8 This is a schematic diagram of approximating dh / dθ using the difference method of the kinematic analysis method of the flexible solar wing scissor-type deployment mechanism of the present invention. DETAILED DESCRIPTION

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0054] In the description of the present invention, “plurality” means two or more than two, unless otherwise clearly and specifically defined.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] The present invention provides a technical solution, which analyzes the kinematics of the scissor-type deployment mechanism and studies its kinematic characteristics to ensure the smooth deployment of the flexible solar wing and avoid impact and stagnation of the deployment mechanism during the deployment process. While performing the kinematic analysis, the mechanism is also subjected to a static analysis as a basis for subsequent motor selection, so as to calculate the driving torque required to be provided at the rod 1 to meet the torque requirements while leaving a certain safety margin to further ensure the stability of the scissor-type deployment mechanism of the flexible solar wing. Please refer to Figures 1 to 8 , the method comprises the following steps:

[0057] The following steps are involved:

[0058] S1: The angle and angular velocity of the prime mover rod 1 are θ and Determine the angle and angular velocity of rod 2 and rod 3. The planar four-bar mechanism is analyzed using a closed vector polygon and the equation is written using its vector column:

[0059]

[0060] θ i Separating the real and imaginary parts by measuring counterclockwise from the positive x-axis gives:

[0061]

[0062] This equation can be used to solve the unknown azimuth angle θ 2 ,θ 3 Solving for θ 3 When the left side of the two fractions contains θ 1 Move the term to the right, square both ends and add them together, let:

[0063]

[0064] The solution is:

[0065]

[0066] Substituting the boundary conditions, when θ 1 =90°, θ 3 =-90°, we can conclude that the sign in should be positive, and we can find θ 3 Then, find θ 2 :

[0067]

[0068] Taking the derivative with respect to time, we get:

[0069]

[0070] That is The complex form of , separating the real and imaginary parts:

[0071]

[0072] The two unknown angular velocities can be solved and

[0073]

[0074] S2: After analyzing the four-bar mechanism, we will analyze the kinematics of the entire mechanism. Due to the characteristics of the four-bar mechanism, the entire mechanism will have lateral displacement during the deployment process. The size of the lateral displacement needs to be calculated to evaluate the impact on the flexible solar wing. The length of each bar is:

[0075]

[0076] The θ obtained by the formula 1 With α 3 , calculate the angles θ and α between rod 1 and rod 3 and the horizontal axis respectively, draw the graph, and the maximum angle difference max(θ-a)=6.8539°;

[0077] S3: Next, calculate the lateral displacement of the mechanism during the deployment process caused by the angle difference:

[0078] First calculate the δ angle in the figure:

[0079]

[0080] Distance of DE:

[0081] DE=0.6cosγ+0.6cosβ+0.6cosδ (3-14)

[0082] Then the lateral distance of the mechanism is:

[0083]

[0084] Plot the lateral displacement w versus the drive angle θ, and its maximum value w max = 0.2377m, obtained when θ = 60.3°;

[0085] S4: Next, the relationship between the deployment height h of the mechanism and the drive angle θ is calculated:

[0086]

[0087] Plot h vs. θ. When fully expanded, h max =6.2912m;

[0088] S5: The kinematic analysis method of the above-mentioned flexible solar wing scissor-type deployment mechanism also includes a static analysis of the deployment process.

[0089] At the same time, in the static analysis, the driving torque of rod 1 is M, and the top of the mechanism is subjected to the tension load Q from the constant force spring. According to the principle of virtual work:

[0090]

[0091] The relationship between h and θ is determined by (2-14), and the difference method is used to find the approximate Draw the image;

[0092] Subsequently, for the top load Q, the required driving torque M decreases as θ increases. At the end of the deployment, when θ=85°, the top load Q=17.64N begins to be applied. At this time, the required driving torque is M=17.64×2.0334=35.8692Nm.

[0093] Embodiment 1

[0094] S1: The angle and angular velocity of the prime mover rod 1 are θ and Determine the angle and angular velocity of rod 2 and rod 3. The planar four-bar mechanism is analyzed using a closed vector polygon, such as Figure 1 As shown, write the equation using its vector:

[0095]

[0096] θ i Separating the real and imaginary parts by measuring counterclockwise from the positive x-axis gives:

[0097]

[0098] This equation can be used to solve the unknown azimuth angle θ 2 ,θ 3 Solving for θ 3 When the left side of the two fractions contains θ 1 Move the term to the right, square both ends and add them together, let:

[0099]

[0100] The solution is:

[0101]

[0102] Substituting the boundary conditions, when θ 1 =90°, θ 3 =-90°, we can conclude that the sign in should be positive, and we can find θ 3 Then, find θ 2 :

[0103]

[0104] Taking the derivative with respect to time, we get:

[0105]

[0106] That is The complex form of , separating the real and imaginary parts:

[0107]

[0108] The two unknown angular velocities can be solved and

[0109]

[0110] S2: After analyzing the four-bar mechanism, we will analyze the kinematics of the entire mechanism. Figure 2 As shown in the figure, due to the characteristics of the four-bar mechanism, the entire mechanism will have lateral displacement during the deployment process. The size of the lateral displacement needs to be calculated to evaluate the impact on the flexible solar wing. The length of each bar is:

[0111]

[0112] The θ obtained by the formula 1 With θ 3 , calculate the angles θ and a between rod 1 and rod 3 and the horizontal axis respectively, and draw a graph. Figure 3 As shown, the maximum angle difference max(θ-α)=6.8539°;

[0113] S3: Next, calculate the lateral displacement of the mechanism during the deployment process caused by the angle difference, Figure 4 As shown:

[0114] First calculate the δ angle in the figure:

[0115]

[0116] Distance of DE:

[0117] DE=0.6cosy+0.6cosβ+0.6cosδ (3-14)

[0118] Then the lateral distance of the mechanism is:

[0119]

[0120] Plot the lateral displacement w versus the drive angle θ, as Figure 5 As shown, its maximum value w max = 0.2377m, obtained when θ = 60.3°;

[0121] S4: Next, the relationship between the deployment height h of the mechanism and the drive angle θ is calculated:

[0122]

[0123] Plotting h versus θ, we can use Figure 6 As shown, when fully expanded h max =6.2912m;

[0124] S5: The kinematic analysis method of the above-mentioned flexible solar wing scissor-type deployment mechanism also includes a static analysis of the deployment process.

[0125] At the same time, by Figure 7 As shown, in the static analysis, the driving torque of rod 1 is M, and the top of the mechanism is subjected to the tension load Q from the constant force spring. According to the principle of virtual work:

[0126]

[0127] The relationship between h and θ is determined by (2-14), and the difference method is used to find the approximate Draw an image such as Figure 8 As shown;

[0128] Subsequently, for the top load Q, the required driving torque M decreases as θ increases. At the end of the deployment, when θ = 85°, the top load Q = 17.64 N is applied. At this time, the required driving torque is M = 17.64 × 2.0334 = 35.8692 Nm.

[0129] Embodiment 2

[0130] S1: The angle and angular velocity of the prime mover rod 1 are θ and Determine the angle and angular velocity of rod 2 and rod 3. The planar four-bar mechanism is analyzed using a closed vector polygon, such as Figure 1 As shown, write the equation using its vector:

[0131]

[0132] θ i Separating the real and imaginary parts by measuring counterclockwise from the positive x-axis gives:

[0133]

[0134] This equation can be used to solve the unknown azimuth angle θ 2 ,θ 3 Solving for θ 3 When the left side of the two fractions contains θ 1 Move the term to the right, square both ends and add them together, let:

[0135]

[0136] The solution is:

[0137]

[0138] Substituting the boundary conditions, when θ 1 =90°, θ 3 =-90°, we can conclude that the sign in should be positive, and we can find θ3 Then, find θ 2 :

[0139]

[0140] Taking the derivative with respect to time, we get:

[0141]

[0142] That is The complex form of , separating the real and imaginary parts:

[0143]

[0144] The two unknown angular velocities can be solved and

[0145]

[0146] S2: After analyzing the four-bar mechanism, we will analyze the kinematics of the entire mechanism. Figure 2 As shown in the figure, due to the characteristics of the four-bar mechanism, the entire mechanism will have lateral displacement during the deployment process. The size of the lateral displacement needs to be calculated to evaluate the impact on the flexible solar wing. The length of each bar is:

[0147]

[0148] The θ obtained by the formula 1 With θ 3 , calculate the angles θ and α between rod 1 and rod 3 and the horizontal axis respectively, and draw the graph. Figure 3 As shown, the maximum angle difference max(θ-a)=6.8539°;

[0149] S3: Next, calculate the lateral displacement of the mechanism during the deployment process caused by the angle difference, Figure 4 As shown:

[0150] First calculate the δ angle in the figure:

[0151]

[0152] Distance of DE:

[0153] DE=0.6cosy+0.6cosβ+0.6cosδ (3-14)

[0154] Then the lateral distance of the mechanism is:

[0155]

[0156] Plot the lateral displacement w versus the drive angle θ, as Figure 5 As shown, its maximum value w max 0.2377m, obtained at θ = 60.3°;

[0157] S4: Next, the relationship between the deployment height h of the mechanism and the drive angle θ is calculated:

[0158]

[0159] Plotting h versus θ, we can use Figure 6 As shown, when fully expanded h max =6.2912m;

[0160] S5: The kinematic analysis method of the above-mentioned flexible solar wing scissor-type deployment mechanism also includes a static analysis of the deployment process.

[0161] At the same time, by Figure 7 As shown, in the static analysis, the driving torque of rod 1 is M, and the top of the mechanism is subjected to the tension load Q from the constant force spring. According to the principle of virtual work:

[0162]

[0163] The relationship between h and θ is determined by (2-14), and the difference method is used to find the approximate Draw an image such as Figure 8 As shown;

[0164] Subsequently, for the Q of the top load, the required driving torque M decreases with the increase of θ. At the end of the unfolding, when α=85°, the top load Q=17.64N begins to be applied. At this time, the required driving torque is M=17.64×2.0334=35.8692Nm, which is used as the basis for motor selection.

[0165] In summary, this method analyzes the kinematics of the scissor-type deployment mechanism, studies its kinematic characteristics, ensures the smooth deployment of the flexible solar wing, avoids impact and stagnation of the deployment mechanism during the deployment process, and performs static analysis on the mechanism while performing the kinematic analysis, which serves as the basis for subsequent motor selection, so as to calculate the driving torque that needs to be provided at rod 1 to meet the torque requirements while leaving a certain safety margin, further ensuring the stability of the flexible solar wing scissor-type deployment mechanism.

[0166] Although the present invention has been described above with reference to the embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed by the present invention may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A kinematic analysis method for a flexible solar wing scissor-type deployment mechanism, characterized in that: The following steps are involved: S1: The angle and angular velocity of the prime mover rod 1 are θ and Determine the angle and angular velocity of rod 2 and rod 3. The planar four-bar mechanism is analyzed using a closed vector polygon and the equation is written using its vector column: θ i Separating the real and imaginary parts by measuring counterclockwise from the positive x-axis gives: This equation can be used to find the unknown azimuth angles θ2 and θ3. When solving for θ3, move the term containing θ1 on the left side of the two fractions to the right side, then square the two ends and add them together. Let: The solution is: Substituting the boundary conditions, when θ1=90°, θ3=-90°, we can conclude that the sign in should be positive. After finding θ3, we can find θ2: Taking the derivative with respect to time, we get: That is The complex form of , separating the real and imaginary parts: The two unknown angular velocities can be solved and S2: After analyzing the four-bar mechanism, we will analyze the kinematics of the entire mechanism. Due to the characteristics of the four-bar mechanism, the entire mechanism will have lateral displacement during the deployment process. The size of the lateral displacement needs to be calculated to evaluate the impact on the flexible solar wing. The length of each bar is: The relationship between θ1 and α3 obtained by the formula is used to calculate the angles θ and α between rod 1 and rod 3 and the horizontal axis, respectively, and the graph is drawn. The maximum angle difference max(θ-α)=6.8539°; S3: Next, calculate the lateral displacement of the mechanism during the deployment process caused by the angle difference: First calculate the δ angle in the figure: Distance of DE: DE=0.6cosγ+0.6cosβ+0.6cosδ (3-14) Then the lateral distance of the mechanism is: Plot the lateral displacement w versus the drive angle θ, and its maximum value w max = 0.2377m, obtained when θ = 60.3°; S4: Next, the relationship between the deployment height h of the mechanism and the drive angle θ is calculated: Plot h vs. θ. When fully expanded, h max =6.2912m; S5: The kinematic analysis method of the above-mentioned flexible solar wing scissor-type deployment mechanism also includes a static analysis of the deployment process.

2. The kinematic analysis method of the flexible solar wing scissor-type deployment mechanism according to claim 1 is characterized by: In the static analysis, the driving torque of rod 1 is M, and the top of the mechanism is subjected to a tension load Q from a constant force spring. According to the principle of virtual work: The relationship between h and θ is determined by (2-14), and the difference method is used to find the approximate Draw the image.

3. The kinematic analysis method of the flexible solar wing scissor-type deployment mechanism according to claim 2 is characterized by: For the top load Q, the required driving torque M decreases as θ increases. At the end of the deployment, when θ = 85°, the top load Q = 17.64N is applied. At this time, the required driving torque is M = 17 .64×2.0334= 35 .8692Nm.

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