A soft crawling caterpillar robot driven by an electrohydrodynamic pump

Abstract

The present invention relates to the fields of microfluidics and electrofluidic technology, and in particular to a soft crawling caterpillar robot driven by an electrohydrodynamic pump. The robot comprises an electrohydrodynamic soft material pump, an artificial muscle, a liquid reservoir, and auxiliary legs. The electrohydrodynamic pump comprises an upper cover plate, a flow channel layer, an electrode layer, and a base layer. The upper cover plate is provided with a flow channel inlet and a flow channel outlet, which are sealed and connected to the liquid reservoir and the artificial muscle, respectively. The flow channel layer, the artificial muscle, and the liquid reservoir are filled with dielectric liquid. The present invention is a soft robot driven by an electrohydrodynamic soft material pump. Electrohydrodynamics is used to achieve a dielectric liquid pumping effect, pumping the dielectric liquid from the liquid reservoir to the artificial muscle. By utilizing the expansion and bending characteristics of the artificial muscle, the robot can achieve an overall forward crawling motion similar to the crawling characteristics of a "caterpillar." At the same time, the robot is flexible and adaptable, and has higher reliability in harsh environments.

Description

Technical Field

[0001] The present invention relates to the field of microfluidics and electrofluid technology, and in particular to a soft crawling caterpillar robot driven by an electrofluidic pump. Background Art

[0002] The history of soft crawling robots dates back to the early 1990s. At that time, researchers began focusing on the integration of biomimetics and robotics to improve the maneuverability and adaptability of robots in complex environments. The earliest soft crawling robots employed simple flexible structures and motion patterns, such as those based on worm-like locomotion. Over time, the design and control technologies for soft crawling robots have significantly improved. Researchers have begun leveraging advanced materials science and engineering to develop more flexible and stretchable materials, as well as deformable mechanisms and sensors. These innovations enable robots to better mimic the movements of biological animals and achieve highly flexible mobility on irregular terrain. The advantages of soft crawling robots lie in their flexibility and adaptability. Compared to traditional rigid robots, soft crawling robots can adapt to complex and irregular environments, such as confined spaces, uneven surfaces, and variable terrain. Their flexible structure enables the robots to move through a variety of motion modes, such as peristalsis, undulation, and crawling, resulting in greater maneuverability and agility. Soft crawling robots also possess strong impact resistance and self-healing capabilities. Due to their flexible structure and material properties, soft robots can deform and cushion impacts, reducing the risk of damage. The impact resistance and self-healing capabilities of soft crawling robots will play an important role in dangerous or complex mission environments. Summary of the Invention

[0003] The purpose of the present invention is to address the problems existing in the background technology and propose a soft crawling caterpillar robot driven by an electrohydrodynamic pump, which has the characteristics of small size, flexibility, scalability and low production cost and can be used for commercial mass production.

[0004] The technical solution of the present invention is a soft crawling caterpillar robot driven by an electrohydrodynamic pump, comprising an electrohydrodynamic pump, artificial muscles, a liquid reservoir and auxiliary legs;

[0005] The electrohydrodynamic pump constitutes the main body of the robot, and the electrohydrodynamic pump is bendable as a whole;

[0006] There are multiple sets of auxiliary feet, all installed on the bottom of the electrohydrodynamic pump;

[0007] The artificial muscle is installed at the front end of the electrohydrodynamic pump, and the fluid reservoir is installed at the rear end of the electrohydrodynamic pump;

[0008] The dielectric liquid is stored in the liquid reservoir. When the electrohydrodynamic pump is connected to an external power source, the dielectric liquid flows from the liquid reservoir into the flow channel layer, and then flows into the artificial muscle through the flow channel layer, causing the artificial muscle to expand and bend.

[0009] The auxiliary foot limits the overall backward movement of the robot;

[0010] The external power is connected in reverse, and the dielectric liquid is sent back to the reservoir, and this reciprocating process enables the robot to crawl forward.

[0011] Preferably, the electrohydrodynamic pump comprises an upper cover plate, a flow channel layer, an electrode layer and a base layer;

[0012] The upper cover plate is provided with a flow channel inlet and a flow channel outlet;

[0013] The flow channel layer is provided with a flow channel, one end of the flow channel is connected to the flow channel inlet, and the other end is connected to the flow channel outlet;

[0014] The electrode layer is a curved cross electrode obtained by laser cutting a copper sheet film, and the first electrode and the second electrode are respectively provided at the left and right ends of the electrode layer;

[0015] The first electrode is connected to the positive pole of the power supply, and the second electrode is connected to the negative pole of the power supply;

[0016] Alternatively, the first electrode is connected to the negative pole of the power supply, and the second electrode is connected to the positive pole of the power supply;

[0017] The intersection of the first electrode and the second electrode is completely exposed in the flow channel of the flow channel layer, and the electrodes are in contact with the dielectric liquid in the flow channel layer;

[0018] The base layer is obtained by laser cutting PDMS material; the base layer is used to support the first electrode and the second electrode in the electrode layer;

[0019] Positioning holes are provided on the upper cover plate, the flow channel layer, the electrode layer and the base layer; and the layers are aligned and assembled in sequence from bottom to top through the positioning holes.

[0020] Preferably, the artificial muscle includes a PDMS layer and a first air chamber; the artificial muscle is made by bonding silicone rubber to the PDMS layer after demolding, and is connected to the flow channel outlet of the upper cover plate through the first through hole, wherein the first air chamber is filled with dielectric liquid.

[0021] Preferably, a second through hole is provided on the top of the liquid reservoir and a limiting foot is provided on the bottom; the liquid reservoir is made by bonding the silicone rubber to the PDMS layer after demolding, and is connected to the flow channel inlet of the upper cover plate through the second through hole, wherein the second air chamber is filled with dielectric liquid, and the limiting foot utilizes the difference in resistance when crawling forward and backward, with very little resistance when crawling forward and very large resistance when crawling backward, thereby limiting the overall backward movement of the robot.

[0022] Preferably, the first air chamber of the artificial muscle, the second air chamber of the liquid reservoir and the flow channel of the flow channel layer are initially filled with dielectric liquid. The artificial muscle and the liquid reservoir have strong expansion and contraction properties and are not easily broken.

[0023] Preferably, the upper cover plate and the flow channel layer are bonded by a glow bonder, the flow channel layer and the base layer are bonded by a glow bonder, and the first electrode and the second electrode in the electrode layer are aligned using a mold to form a soft material pump.

[0024] Preferably, when the dielectric liquid is injected into the artificial muscle, the first air chamber will expand, thereby driving the bending of the artificial muscle and realizing the forward crawling movement of the entire robot.

[0025] Preferably, the artificial muscle, the liquid reservoir and the auxiliary foot are all obtained by curing and demolding the poured silicone rubber through a 3D printing mold, wherein the artificial muscle and the liquid reservoir are demolded and then bonded with semi-cured PDMS.

[0026] Preferably, the upper cover plate is made of polyethylene terephthalate (PET) material through laser processing and can be bent at any angle.

[0027] Preferably, the flow channel layer is made of soft silicone material through laser processing, and is bendable and has a smooth surface.

[0028] Compared with the prior art, the present invention has the following beneficial technical effects:

[0029] The present invention provides a soft crawling caterpillar driven by an electrohydrodynamic pump. Two electrodes in the electrode layer are connected to an external 8000V DC power supply and a ground connection, respectively. When powered on, the high voltage ionizes the dielectric liquid in the flow channel, causing it to flow from the liquid reservoir through the upper cover plate into the flow channel layer. The liquid then flows through the flow channel layer into the artificial muscle, causing it to expand and bend. Under the action of auxiliary legs and limiting legs, the "caterpillar" crawls forward as a whole. Then, an external 8000V DC power supply is connected in the opposite direction to pump the dielectric liquid back into the liquid reservoir, causing the "caterpillar" to move forward one step. This repetitive cycle continuously enables the "caterpillar" to crawl forward continuously.

[0030] The invention is based on a soft crawling caterpillar driven by an electrohydrodynamic pump, and the materials selected are all soft materials; and the finished product has the characteristics of small size, flexibility, scalability and low production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of a soft crawling caterpillar driven by an electrohydrodynamic pump according to an embodiment of the present invention;

[0032] Figure 2 1 is an exploded view of the assembly of an electrohydrodynamic pump according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic structural diagram of an upper cover plate in an embodiment of the present invention;

[0034] Figure 4 Schematic diagram of the structure of the flow channel layer in an embodiment of the present invention;

[0035] Figure 5 is a schematic structural diagram of an electrode layer in an embodiment of the present invention;

[0036] Figure 6 is a schematic structural diagram of a base layer in an embodiment of the present invention;

[0037] Figure 7 is a schematic structural diagram of an artificial muscle in an embodiment of the present invention;

[0038] Figure 8 Schematic diagram of the structure of the liquid storage tank in an embodiment of the present invention;

[0039] Figure 9 is a schematic structural diagram of an auxiliary foot in an embodiment of the present invention;

[0040] Figure 10 Result diagram of pressure test of electrohydrodynamic pump at different voltages in an embodiment of the present invention;

[0041] Figure 11 Graph showing the results of flow rate experiments of an electrohydrodynamic pump at different voltages according to an embodiment of the present invention;

[0042] Figure 12 Graph showing the results of a caterpillar crawling distance experiment in an embodiment of the present invention.

[0043] Figure numerals: 1. electrohydrodynamic pump; 2. artificial muscle; 21. first through hole; 22. first air chamber; 23. PDMS layer; 3. liquid reservoir; 31. second through hole; 32. second air chamber; 33. limiting foot; 4. auxiliary foot; 5. upper cover plate; 51. flow channel inlet; 52. flow channel outlet; 6. flow channel layer; 61. flow channel; 7. electrode layer; 71. first electrode; 72. second electrode; 8. base layer; 81. positioning hole. DETAILED DESCRIPTION

[0044] Example 1

[0045] like Figure 1 As shown, the present invention proposes a soft crawling caterpillar robot driven by an electrohydrodynamic pump, which includes an electrohydrodynamic pump 1, an artificial muscle 2, a liquid reservoir 3 and an auxiliary foot 4.

[0046] like Figure 2As shown, the electrohydrodynamic pump consists of an upper cover plate 5, a flow channel layer 6, an electrode layer 7 and a base layer 8, and the whole can be bent to a certain extent.

[0047] like Figure 3 As shown, the upper cover plate 5 is provided with a flow channel inlet 51 and a flow channel outlet 52;

[0048] like Figure 4 As shown, a flow channel 61 is provided on the flow channel layer 6 , one end of the flow channel 61 is connected to the flow channel inlet 51 , and the other end is connected to the flow channel outlet 52 ;

[0049] like Figure 5 As shown, the electrode layer 7 is a 50 μm copper sheet obtained by laser cutting according to the designed pattern and is externally connected to a 0-8000 V DC power supply. The first electrode 71 is connected to the positive electrode, the second electrode 72 is connected to the negative electrode, and the cross section is completely exposed in the flow channel 61 of the flow channel layer;

[0050] like Figure 6 As shown, the base layer 8 is made of PDMS material and obtained by laser cutting;

[0051] The soft material pump based on electrohydrodynamics is aligned and assembled from bottom to top through the four positioning holes set on each layer, where the flow channel inlet 51 is connected to the left end 61 of the flow channel, the flow channel outlet 52 is connected to the right end 61 of the flow channel, and the cross-electrode part in the electrode layer 7 is completely exposed in the flow channel 61 of the flow channel layer.

[0052] like Figure 7 As shown, the artificial muscle 2 is made of silicone rubber after demoulding and bonding with the PDMS layer 23, and is connected to the flow channel outlet 52 of the upper cover plate 5 through the first through hole 21, wherein the first air chamber 22 is filled with dielectric liquid;

[0053] like Figure 8 As shown, the liquid reservoir 3 is also made by bonding the silicone rubber to the PDMS layer after demoulding, and is connected to the flow channel inlet 51 of the upper cover plate 5 through the second through hole 31. The second air chamber 32 is filled with dielectric liquid, and the limit foot 33 limits the overall backward movement of the "caterpillar";

[0054] like Figure 9 As shown, the auxiliary foot 4 limits the overall backward movement of the "caterpillar";

[0055] The working process of the soft crawling caterpillar driven by the electrohydrodynamic pump in the above embodiment is as follows:

[0056] The first air chamber 22 of the artificial muscle 2, the second air chamber 32 of the liquid reservoir 3, and the flow channel of the flow channel layer 6 are initially filled with dielectric liquid. The artificial muscle 2 and the liquid reservoir 3 both have strong expansion and contraction properties and are not easily broken. The two electrodes 71 and 72 of the electrode layer 7 are respectively connected to an external 8000V DC power supply and grounded. After power is turned on, the high voltage is used to ionize the dielectric liquid in the flow channel 61, causing the dielectric liquid to flow from the liquid reservoir 3 through the upper cover 5 into the flow channel layer 6, and then through the flow channel layer 6 into the artificial muscle 2, causing the artificial muscle 2 to expand and bend. The center of gravity of the entire robot is biased toward one end of the artificial muscle 2, and the electrohydrodynamic pump 1 is subjected to force to stretch and bend. Figure 1 As shown; an auxiliary foot 4 and a limit foot 33 are provided in an "L" shape, and the resistance in the forward direction is smaller than the resistance in the backward direction; the bent electrohydrodynamic pump 1 makes the limit foot 33 contact the ground, so that under the action of the auxiliary foot 4 and the limit foot 33, the robot as a whole crawls forward, and then an 8000V DC power is connected in the reverse direction to pump the dielectric liquid back to the liquid reservoir 3, so that the robot as a whole moves forward one step, and this reciprocating process is continuously repeated, thereby realizing the continuous forward crawling of the "caterpillar" as a whole.

[0057] The flow channel inlet 51 and the flow channel outlet 52 of the upper cover plate 5 correspond one-to-one to the left end and the right end of the flow channel 61 on the flow channel layer 6 .

[0058] The material surfaces of the upper cover plate 5 , the flow channel layer 6 and the base layer 8 are smooth and will not hinder the flow of the dielectric liquid, thereby generating smaller flow resistance and increasing the pumping speed.

[0059] The order in which the electrodes 71 and 72 of the electrode layer 7 are connected to the external voltage can be changed to achieve a bidirectional pumping effect.

[0060] The electrodes 71 and 72 in the electrode layer 7 can increase the number of crossed electrode pairs to achieve a higher pumping rate and pumping pressure, and the curved crossed electrodes have a better ionization effect than the straight crossed electrodes, thereby generating a higher pumping speed.

[0061] During fabrication, the desired structure is laser-engraved onto a double-sided adhesive material covered with a PVC substrate. For bonding, a plasma cleaner is used to modify the microstructure of the various layers, followed by surface treatment. A positioning fixture then inserts locating pins into the locating holes of the various layers for securement and bonding.

[0062] In this embodiment, a soft crawling caterpillar driven by an electrohydrodynamic pump is used to realize a type of soft crawling robot composed of soft matter that is small in size, flexible, scalable, and has low production cost. Figure 10-12 shown

[0063] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A soft crawling caterpillar robot driven by an electrohydrodynamic pump, characterized in that: It includes an electrohydrodynamic pump (1), an artificial muscle (2), a liquid reservoir (3) and an auxiliary foot (4); The electrohydrodynamic pump (1) constitutes the main body of the robot, and the electrohydrodynamic pump (1) is bendable as a whole; The auxiliary legs (4) are L-shaped and are provided in multiple groups, all of which are installed at the bottom of the electrohydrodynamic pump (1); The artificial muscle (2) is installed at the front end of the electrohydrodynamic pump (1), and the liquid reservoir (3) is installed at the rear end of the electrohydrodynamic pump; The dielectric liquid is stored in the liquid reservoir (3). When the electrohydrodynamic pump (1) is connected to an external power source, the dielectric liquid flows from the liquid reservoir (3) into the flow channel layer (6), and then flows into the artificial muscle (2) through the flow channel layer (6), so that the artificial muscle (2) expands and bends. The auxiliary foot (4) utilizes the difference in resistance when crawling forward and backward. When moving forward, the resistance is very small, but when moving backward, there is a certain resistance, which limits the backward movement of the robot as a whole. The external power is connected in the reverse direction, and the dielectric liquid is sent back to the liquid storage tank (3), and the robot crawls forward continuously.

2. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 1, characterized in that: The electrohydrodynamic pump (1) comprises an upper cover plate (5), a flow channel layer (6), an electrode layer (7) and a base layer (8); The upper cover plate (5) is provided with a flow channel inlet (51) and a flow channel outlet (52); A flow channel (61) is provided on the flow channel layer (6), one end of the flow channel (61) is connected to the flow channel inlet (51), and the other end is connected to the flow channel outlet (52); The electrode layer (7) is a curved cross electrode obtained by laser cutting a copper sheet film, and a first electrode (71) and a second electrode (72) are respectively provided at the left and right ends of the electrode layer (7); The first electrode (71) is connected to the positive electrode of the power supply, and the second electrode (72) is connected to the negative electrode of the power supply; Alternatively, the first electrode (71) is connected to the negative electrode of the power supply, and the second electrode (72) is connected to the positive electrode of the power supply; The intersection of the first electrode (71) and the second electrode (72) is completely exposed in the flow channel (61) of the flow channel layer, and the electrodes are in contact with the dielectric liquid in the flow channel layer (6); The base layer (8) is obtained by laser cutting a PDMS material; the base layer (8) is used to support the first electrode (71) and the second electrode (72) in the electrode layer (7); Positioning holes are provided on the upper cover plate (5), the flow channel layer (6), the electrode layer (7) and the base layer (8); and the layers are aligned and assembled in sequence from bottom to top through the positioning holes.

3. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 1, characterized in that: The artificial muscle (2) comprises a PDMS layer (23) and a first air chamber (22); the artificial muscle (2) is made by bonding silicone rubber to the PDMS layer (23) after demoulding, and is connected to a flow channel outlet (52) of an upper cover plate (5) through a first through hole (21), wherein the first air chamber (22) is filled with a dielectric liquid.

4. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 1, characterized in that: A second through hole (31) is provided on the top of the liquid reservoir (3), and a limiting foot (33) is provided on the bottom; the liquid reservoir (3) is made by bonding a silicone rubber layer with a PDMS layer after demoulding, and is communicated with a flow channel inlet (51) of an upper cover plate (5) through the second through hole (31), wherein the second air chamber (32) is filled with a dielectric liquid, and the limiting foot (33) utilizes the difference in resistance when crawling forward and backward, with very little resistance when crawling forward and very much resistance when crawling backward, thereby limiting the backward movement of the entire robot.

5. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 1, characterized in that: The first air chamber (22) of the artificial muscle (2), the second air chamber (32) of the liquid reservoir (3), and the flow channel (61) of the flow channel layer (6) are filled with dielectric liquid in an initial state.

6. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 2, characterized in that: The upper cover plate (5) and the flow channel layer (6) are bonded by a glow bonder, the flow channel layer (6) and the base layer (8) are bonded by a glow bonder, and the first electrode (71) and the second electrode (72) in the electrode layer (7) are aligned by a mold to form a soft material pump.

7. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 2, characterized in that: When dielectric liquid is injected into the artificial muscle (2), the first air chamber (22) expands, thereby driving the bending of the artificial muscle and realizing the forward crawling movement of the entire robot.

8. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 2, characterized in that: The artificial muscle (2), the liquid reservoir (3) and the auxiliary foot (4) are all obtained by curing and demoulding the poured silicone rubber through a 3D printing mold, wherein the artificial muscle (2) and the liquid reservoir (3) are demoulded and then bonded with semi-cured PDMS.

9. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 2, characterized in that: The upper cover plate (5) is made of polyethylene terephthalate (PET) material through laser processing and can be bent at any angle.

10. The soft crawling caterpillar robot driven by an electrohydrodynamic pump according to claim 2, characterized in that: The flow channel layer (6) is made of soft silicone material through laser processing and is bendable and has a smooth surface.

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