Two-degree-of-freedom soft body drive for rotational transport

Abstract

The application provides a two-degree-of-freedom soft driver for rotary conveying, comprising a driving soft body, wherein a hole allowing a puncture needle to pass through is arranged in the driving soft body, the periphery of the hole is provided with a forward secondary spiral cavity and a reverse secondary spiral cavity, the profile of any one of the forward secondary spiral cavity and the reverse secondary spiral cavity is a sinusoidal secondary spiral curve; when the forward secondary spiral cavity and / or the reverse secondary spiral cavity expands, the expansion direction thereof is in frictional contact with the puncture needle passing through the hole, so as to generate an inclined tangential force. Through the three-dimensional wave principle of the forward secondary spiral cavity and the reverse secondary spiral cavity, linear and rotary decoupling conveying of the puncture needle is realized, and the driver has the characteristics of simplicity, small size, long conveying stroke and the like, solves the problems of space limitation, small stroke, complex rotary and linear decoupling mechanism and the like in the clinical puncture process, and has a locking function.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of soft body driver, in particular, to a two-degree-of-freedom soft body driver for rotary conveying. BACKGROUND

[0002] Rotary driving and linear driving are two common driving forms. In many application scenarios, linear motion and rotary motion often need to be synchronized or coordinated to meet the operation requirements of actuators. For example, when performing a biopsy, a biopsy needle needs to puncture and rotate to shear tumor tissue, thereby collecting a biopsy sample. This operation is completed manually in a clinical setting, which requires a high level of skill from the operator. By designing an automatically controlled device, the operator can be assisted in remote operation to complete the fine operation of rotary conveying.

[0003] The existing Chinese patent application document with the publication number CN214326271U discloses a spiral conveying device that can linearly move in rotation, which includes a conveying cylinder, a rotary spiral, a positioning structure, a linear movement mechanism, and a linear driving mechanism. One end of the conveying cylinder is provided with a feeding port, and the other end is provided with a discharging port. The rotary spiral is arranged in the conveying cylinder and is used to convey the material from the feeding port to the discharging port. The positioning structure is in positioning connection with the rotary spiral. The linear movement mechanism includes a sliding part and a fixed part, the sliding part is in linear sliding connection with the fixed part, and the sliding part is in positioning connection with the positioning structure. The linear driving mechanism is connected with the sliding part and is used to drive the sliding part to move linearly.

[0004] The conveying device in the prior art is difficult to achieve long-stroke conveying and is subject to the size of the movement guide rail. The rotary conveying module needs to rely on a complex mechanical transmission system, so it is difficult to be miniaturized and arranged in the clamping device of the puncture needle, and there is room for improvement. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a two-degree-of-freedom soft body driver for rotary conveying.

[0006] According to the two-degree-of-freedom soft body driver for rotary conveying provided by the present application, the driving soft body is provided with a hole for allowing the puncture needle to pass through, the periphery of the hole is provided with a positive secondary spiral cavity and a reverse secondary spiral cavity, the profile of any of the positive secondary spiral cavity and the reverse secondary spiral cavity is a sinusoidal secondary spiral curve; when the positive secondary spiral cavity and / or the reverse secondary spiral cavity expands, the expansion direction is in frictional contact with the puncture needle passing through the hole, thereby generating an inclined tangential force.

[0007] Preferably, the number of positive secondary spiral cavities is four, and the number of reverse secondary spiral cavities is four.

[0008] Preferably, the medium that causes the expansion of the positive secondary spiral lumen and / or the negative secondary spiral lumen comprises a gas or a liquid; the positive secondary spiral lumen and / or the negative secondary spiral lumen is caused to expand under the action of gas pressure; or, the positive secondary spiral lumen and / or the negative secondary spiral lumen is caused to expand under the action of liquid volume.

[0009] Preferably, for the driving sequence of the positive secondary spiral lumen, the input pressure of the positive secondary spiral lumen is defined as: P1-1, P1-2, P2-1, P2-2 by sequentially designing four different driving sequences.

[0010] f P1-1 (t) = 0.1 sin(2πt)

[0011] f P1-2 (t) = -0.1 sin(2πt)

[0012] f P2-1 (t) = 0.1 sin(2πt - 1 / 2π)

[0013] f P2-2 (t) = -0.1 sin(2πt - 1 / 2π)

[0014] The positive rotation and conveying motion is realized, P1-1 is the input pressure of the first positive secondary spiral lumen, P1-2 is the input pressure of the second positive secondary spiral lumen, P2-1 is the input pressure of the third positive secondary spiral lumen, P2-2 is the input pressure of the fourth positive secondary spiral lumen, and t represents time.

[0015] Preferably, the same preset gas pressure is input to the four positive secondary spiral lumens at the same time to lock the position of the puncture needle in the lumen.

[0016] Preferably, for the driving sequence of the negative secondary spiral lumen, the input pressure of the negative secondary spiral lumen is defined as: P3-1, P3-2, P4-1, P4-2 by sequentially designing four different driving sequences.

[0017] f P3-1 (t) = 0.1 sin(2πt)

[0018] f P3-2 (t) = -0.1 sin(2πt)

[0019] f P4-1 (t) = -0.1 sin(2πt - 1 / 2π)

[0020] f P4-2 (t) = 0.1 sin(2πt - 1 / 2π)

[0021] The negative rotation and conveying motion can be realized, P3-1 is the input pressure of the first negative secondary spiral cavity, P3-2 is the input pressure of the second negative secondary spiral cavity, P4-1 is the input pressure of the third negative secondary spiral cavity, P4-2 is the input pressure of the fourth negative secondary spiral cavity, and t represents time.

[0022] Preferably, the decoupling motion of each combination is realized by adjusting the phase relationship of the positive secondary spiral cavity and the reverse secondary spiral cavity.

[0023] The staggered spiral development of the wave crest and the wave trough of the positive secondary spiral cavity and the reverse secondary spiral cavity sequentially offsets the intersection sites and retains uniform curvature change, and ensures the consistency of the contact force size at different points of the whole drive.

[0024] x (theta) = (R + rcos (theta * n)) * cos (theta)

[0025] y (theta) = (R + rcos (theta * n)) * sin (theta)

[0026] z (theta) = R * theta * tan (alpha)

[0027] Wherein, theta belongs to [0, 2pi / n], R is the radius of the primary spiral, r is the amplitude of the secondary spiral, theta is the spiral angle, which is used to describe the motion position of the spiral curve, alpha is the slope, which determines the longitudinal change rate of the spiral line, and n is the intersection number in 1 spiral period.

[0028] Preferably, the positive secondary spiral cavity and the reverse secondary spiral cavity are connected with a pressure controller or a flow controller.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] 1. The present application realizes the decoupling conveying of the linear and rotation of the puncture needle by adopting the three-dimensional wave principle of the positive secondary spiral cavity and the reverse secondary spiral cavity, has the characteristics of simplicity, small size and long conveying stroke, solves the problems of space limitation, small stroke, complex rotation and linear conveying decoupling mechanism in the clinical puncture process, and has the locking function.

[0031] 2. The present application realizes the decoupling conveying of the linear and rotation of the puncture needle by adopting the three-dimensional wave principle of the positive secondary spiral cavity and the reverse secondary spiral cavity, has the characteristics of simplicity, small size and long conveying stroke, solves the problems of space limitation, small stroke, complex rotation and linear conveying decoupling mechanism in the clinical puncture process, and has the locking function. DETAILED DESCRIPTION

[0032] Other features, objects, and advantages of the application will become apparent from the detailed description of the non-limiting embodiments with reference to the drawings:

[0033] Figure 1 A structure schematic diagram of the present application mainly embodies three-dimensional wave pneumatic soft drive rotating linear conveying decoupling;

[0034] Figure 2 A schematic diagram of the present application mainly embodies forward and reverse cavity distribution mode;

[0035] Figure 3 A pressure control curve of the four driving cavities of the present application;

[0036] Figure 4 A schematic diagram of the present application mainly embodies different phase space secondary helix spiral curves;

[0037] Figure 5 A simulation diagram of the present application mainly embodies the distribution of the surface contact points of the puncture needle changing with time in linear motion and rotary motion.

[0038] Shown in the figure: 100, driving soft; 101, forward secondary helix cavity; 102, reverse secondary helix cavity; 103, puncture needle. DETAILED DESCRIPTION

[0039] The present application will be described in detail below with specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of changes and improvements can be made. These all belong to the protection scope of the present application.

[0040] As Figure 1 shown, according to the two-degree-of-freedom soft driver for rotary conveying provided by the present application, the driving soft 100 is provided with a hole allowing the puncture needle 103 to pass through, the hole is provided with a forward secondary helix cavity 101 and a reverse secondary helix cavity 102 on the side, the profile of any forward secondary helix cavity 101 and reverse secondary helix cavity 102 is a sinusoidal secondary helix curve. When the forward secondary helix cavity 101 and / or the reverse secondary helix cavity 102 expands, the expansion direction is in frictional contact with the puncture needle 103 passing through the hole, thereby generating an inclined tangential force.

[0041] The technical scheme of the application adopts the three-dimensional wave principle of the forward secondary spiral cavity 101 and the reverse secondary spiral cavity 102 to realize the decoupling transmission of the linear and rotation of the puncture needle 103. The application has the characteristics of simplicity, small size and long transmission stroke, and solves the problems of space limitation, small stroke, and complex rotation and linear decoupling mechanism in the clinical puncture process. By designing the forward secondary spiral cavity 101 and the reverse secondary spiral cavity 102, the rotation and linear decoupling motion can be realized. The rotation or linear delivery of the biopsy needle is realized, and the locking function is also provided. Compared with the traditional rotation and linear transmission device, the application has the characteristics of simplicity, small size and long transmission stroke.

[0042] As shown in Figure 2 and Figure 3 , specifically, the number of the forward secondary spiral cavity 101 is four, and the number of the reverse secondary spiral cavity 102 is four. The medium for expanding the forward secondary spiral cavity 101 and / or the reverse secondary spiral cavity 102 includes gas or liquid. The forward secondary spiral cavity 101 and / or the reverse secondary spiral cavity 102 are expanded under the action of gas pressure; or, the forward secondary spiral cavity 101 and / or the reverse secondary spiral cavity 102 are expanded under the action of liquid volume.

[0043] More specifically, the drive soft body 100 has eight independent drive cavities inside, and each drive cavity is a sinusoidal secondary spiral curve.

[0044] For the driving sequence of the forward secondary spiral cavity 101, four different driving sequences are designed in sequence, and the input pressure of the forward secondary spiral cavity 101 is defined as: P1-1, P1-2, P2-1, P2-2.

[0045] f P1-1 (t) = 0.1 sin(2πt)

[0046] f P1-2 (t) = -0.1 sin(2πt)

[0047] f P2-1 (t) = 0.1 sin(2πt-1 / 2π)

[0048] f P2-2 (t) = -0.1 sin(2πt-1 / 2π)

[0049] The positive rotation and conveying motion can be realized, P1-1 is the input pressure of the first positive secondary spiral channel 101, P1-2 is the input pressure of the second positive secondary spiral channel 101, P2-1 is the input pressure of the third positive secondary spiral channel 101, P2-2 is the input pressure of the fourth positive secondary spiral channel 101, and t represents time. The same preset gas pressure is input to the four positive secondary spiral channels 101, so that the position of the puncture needle 103 in the channel is locked.

[0050] For the driving sequence of the negative secondary spiral channel, four different driving sequences are designed in sequence, and the input pressure of the negative secondary spiral channel is defined as: P3-1, P3-2, P4-1, P4-2.

[0051] f P3-1 (t) = 0.1 sin (2πt)

[0052] f P3-2 (t) = -0.1 sin (2πt)

[0053] f P4-1 (t) = -0.1 sin (2πt-1 / 2π)

[0054] f P4-2 (t) = 0.1 sin (2πt-1 / 2π)

[0055] The negative rotation and conveying motion can be realized, P3-1 is the input pressure of the first negative secondary spiral channel, P3-2 is the input pressure of the second negative secondary spiral channel, P4-1 is the input pressure of the third negative secondary spiral channel, P4-2 is the input pressure of the fourth negative secondary spiral channel, and t represents time.

[0056] By adjusting the phase relationship of the positive secondary spiral channel 101 and the negative secondary spiral channel 102, the decoupling motion of two-by-two combination can be realized. The staggered spiral development of the wave crest and the wave trough of the positive secondary spiral channel 101 and the negative secondary spiral channel 102, the staggered cross points, and the uniform curvature change ensure the consistency of the contact force at different points during the whole driving. The formula of the secondary spiral curve is as follows:

[0057] x(θ) = (R + rcos(θ·n))·cos(θ)

[0058] y(θ) = (R + rcos(θ·n))·sin(θ)

[0059] z(θ) = R·θ·tan(α)

[0060] Wherein, θ∈[0, 2π / n], R: the radius of the primary helix; r: the amplitude of the wave on the secondary helix; θ: the helix angle, used to describe the movement position of the helix along the curve; α: the slope, determines the longitudinal rate of change of the helix; n: the number of intersections in 1 helix period.

[0061] The 3D display of the secondary helix curve drawn according to the above formula is shown in Figure 4 Figure 5 The simulation results of the surface contact point of the puncture needle 103 are shown, and the rotating conveying decoupling peristaltic motion of arranging the forward and reverse secondary helix curves in the same driving unit is achieved.

[0062] It should be noted that any forward secondary helix channel 101 and reverse secondary helix channel 102 are connected with a pressure controller or a flow controller to ensure the stability of the driving. The same preset gas pressure is input to the four forward secondary helix channels 101 and / or negative secondary helix channels, so as to lock the position of the puncture needle 103 in the channel. It should be further noted that the internal structure of different sections in one cycle of the soft driver is different.

[0063] The structural design size of the present application can change the design parameters such as the hole diameter, the helix angle, the overall driving length (i.e. the period of the channel wave), the material hardness, etc. according to the actual application requirements, to realize different clamping forces, clamping sizes, conveying rotation speeds and other performance requirements. The manufacturing method of the present application can be realized by soft material additive manufacturing, soft material injection molding and other methods. The control fluid of the present application is not limited to gas pressure control, but also can use liquid for flow control, and the size of the channel can be changed by controlling the volume of the liquid in the cavity.

[0064] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0065] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict.​

Claims

1. A two-degree-of-freedom soft actuator for rotary conveying, characterized in that, The device includes a drive software (100), which has a channel that allows a puncture needle (103) to pass through. The channel has a forward quadratic spiral cavity (101) and a reverse quadratic spiral cavity (102) on its periphery. The outline of either the forward quadratic spiral cavity (101) or the reverse quadratic spiral cavity (102) is a sinusoidal quadratic spiral curve. When the forward secondary spiral cavity (101) and / or the reverse secondary spiral cavity (102) expand, their expansion direction comes into frictional contact with the puncture needle (103) passing through the cavity, thereby generating an inclined tangential force; By adjusting the phase relationship between the forward secondary helical cavity (101) and the reverse secondary helical cavity (102), the decoupled motion of the two combinations can be achieved. The alternating spiral unfolding of the peaks and troughs of the forward and reverse quadratic spiral channels (101 and 102) staggers the intersection points and maintains a uniform curvature change, ensuring the consistency of the contact force at different points of the entire drive. The formula for the quadratic spiral curve is shown below: Where θ∈[0,2π / n], R: radius of the first-order spiral; r: amplitude of the oscillation on the second-order spiral; θ: spiral angle, used to describe the position of the spiral along the curve; α: slope, which determines the longitudinal rate of change of the spiral; n: number of crossovers in one spiral cycle.

2. The two-degree-of-freedom soft actuator for rotary conveying as described in claim 1, characterized in that, The number of the forward secondary spiral cavities (101) is four, and the number of the reverse secondary spiral cavities (102) is four.

3. The two-degree-of-freedom soft actuator for rotary conveying as described in claim 1, characterized in that, The medium that causes the positive secondary helical channel (101) and / or the negative secondary helical channel (102) to expand includes gas or liquid; The forward secondary helical cavity (101) and / or the reverse secondary helical cavity (102) expand under the action of gas pressure; Alternatively, the forward secondary helical channel (101) and / or the reverse secondary helical channel (102) expand under the influence of the liquid volume.

4. The two-degree-of-freedom soft actuator for rotary conveying as described in claim 1, characterized in that, For the driving sequence of the positive double helical cavity (101), by designing four different driving sequences in sequence, the input pressure of the positive double helical cavity (101) is defined as: P1-1, P1-2, P2-1, P2-2; To achieve forward rotation and conveying motion, P1-1 is the input pressure of the first forward secondary spiral cavity (101), P1-2 is the input pressure of the second forward secondary spiral cavity (101), P2-1 is the input pressure of the third forward secondary spiral cavity (101), P2-2 is the input pressure of the fourth forward secondary spiral cavity (101), and t represents time.

5. The two-degree-of-freedom soft actuator for rotary conveying as described in claim 1, characterized in that, Simultaneously, the same preset gas pressure is input into the four positive secondary spiral cavities (101) to lock the position of the puncture needle (103) in the cavities.

6. The two-degree-of-freedom software actuator for rotary conveying as described in claim 1, characterized in that, For the driving sequence of the negative double helical cavity, by designing four different driving sequences in sequence, the input pressure of the negative double helical cavity is defined as: P3-1, P3-2, P4-1, P4-2. It can realize negative rotation and conveying motion. P3-1 is the input pressure of the first negative secondary spiral cavity, P3-2 is the input pressure of the second negative secondary spiral cavity, P4-1 is the input pressure of the third negative secondary spiral cavity, P4-2 is the input pressure of the fourth negative secondary spiral cavity, and t represents time.

7. The two-degree-of-freedom soft actuator for rotary conveying as described in claim 1, characterized in that, Each of the forward secondary spiral channels (101) and the reverse secondary spiral channels (102) is connected to a pressure controller or a flow controller.

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