BIOMIMETIC TURTLE

Abstract

A biomimetic turtle includes a waterproof housing unit, front and hind limb driving motors, and front and hind limb modules. The waterproof housing unit includes a waterproof casing defining a waterproof space therein, and having front and hind limb connecting holes in fluid communication with the waterproof space, and front and hind limb connectors connected respectively to the front and hind limb connecting holes. Each front limb driving motor includes a front limb driving shaft connected to a respective one of the front limb connectors. Each hind limb driving motor includes a hind limb driving shaft connected to a respective one of the hind limb connectors. The front and hind limb modules are connected respectively and detachably to the front and hind limb connectors, and are driven respectively by the front and hind limb driving motors via the front and hind limb connectors as being controlled by a control unit.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Taiwanese Invention Patent Application No. 113101715, filed on Jan. 16, 2024, and incorporated by reference herein in its entirety.

FIELD

The disclosure relates to a biomimetic robot, and more particularly to a biomimetic turtle.

BACKGROUND

Generally, a conventional biomimetic turtle includes front limbs and hind limbs that have a relatively complicated transmission mechanism for emulating movement and swimming motion of a turtle in the water. Each of the front limbs and the hind limbs includes a plurality of joints connected to a plurality of output shafts that are driven by a plurality of motors to control movement of the conventional biomimetic turtle, which is quite troublesome. In addition, in a case where the conventional biomimetic turtle employs motors, gears, pulleys, belts, link rods, etc. as the transmission mechanism, it is necessary to provide a waterproof function for the abovementioned components. For example, a waterproof motor that is way more expensive than an ordinary motor without a waterproof function is employed in the conventional biomimetic turtle, so the conventional biomimetic turtle is costly to manufacture. Furthermore, since the front limbs and the hind limbs are controlled by a plurality of motors and have a relatively complicated structure, it is usually troublesome for maintenance of the conventional biomimetic turtle.

SUMMARY

Therefore, an object of the disclosure is to provide a biomimetic turtle that can alleviate at least one of the drawbacks of the prior art.

According to the disclosure, the biomimetic turtle includes a waterproof housing unit, two front limb driving motors, two hind limb driving motors, two front limb modules, two hind limb modules, and a control unit. The waterproof housing unit includes a waterproof casing, two front limb connectors, and two hind limb connectors. The waterproof casing defines a waterproof space therein, and has two front limb connecting holes that are in fluid communication with the waterproof space, and two hind limb connecting holes that are in fluid communication with the waterproof space. The front limb connectors are connected respectively to the front limb connecting holes. The hind limb connectors are connected respectively to the hind limb connecting holes. The front limb driving motors are disposed in the waterproof space. Each of the front limb driving motors includes a front limb driving shaft that is connected to a respective one of the front limb connectors. The hind limb driving motors are disposed in the waterproof space. Each of the hind limb driving motors includes a hind limb driving shaft that is connected to a respective one of the hind limb connectors. The front limb modules are connected respectively and detachably to the front limb connectors, and are driven respectively by the front limb driving motors via the front limb connectors. The hind limb modules are connected respectively and detachably to the hind limb connectors, and are driven respectively by the hind limb driving motors via the hind limb connectors. The control unit is mounted in the waterproof space of the waterproof casing and is configured to control the front limb driving motors and the hind limb driving motors.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings. It is noted that various features may not be drawn to scale.

FIG. 1 is a perspective view illustrating an embodiment of a biomimetic turtle according to the present disclosure.

FIG. 2 is a partly exploded perspective view of the embodiment, illustrating a decorative casing, a waterproof casing, two front limb modules and two hind limb modules of the biomimetic turtle.

FIG. 3 is a fragmentary, partly exploded perspective view of the embodiment, without the decorative casing.

FIG. 4 is another fragmentary, partly exploded perspective view of the embodiment, illustrating a structure of the biomimetic turtle without the decorative casing, the front limb modules and the hind limb modules.

FIG. 5 is a fragmentary cutaway perspective view of the embodiment, illustrating a weight module and a head module of the biomimetic turtle.

FIG. 6 is a fragmentary schematic sectional view illustrating the weight module and the head module of the embodiment.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.

It should be noted herein that for clarity of description, spatially relative terms such as “top,” “bottom,” “upper,” “lower,” “on,” “above,” “over,” “downwardly,” “upwardly” and the like may be used throughout the disclosure while making reference to the features as illustrated in the drawings. The features may be oriented differently (e.g., rotated 90 degrees or at other orientations) and the spatially relative terms used herein may be interpreted accordingly.

Referring to FIGS. 1 to 4, an embodiment of a biomimetic turtle 100 according to the disclosure is adapted to be movable in the water. The biomimetic turtle 100 includes a waterproof housing unit 1, a decorative cover 2, a control unit 3, two front limb driving motors 4, two hind limb driving motors 5, two front limb modules 6, two hind limb modules 7, a weight module 8, and a head module 9.

The waterproof housing unit 1 includes a waterproof casing 11, two front limb connectors 12, two hind limb connectors 13 (only one is visible), and a waterproof cover 14. The waterproof casing 11 defines a waterproof space 111 therein, and has two front limb connecting holes 112 that are in fluid communication with the waterproof space 111, two hind limb connecting holes 113 (only one is visible) that are in fluid communication with the waterproof space 111, and a head connecting hole 114 (see FIG. 6) that is in fluid communication with the waterproof space 111. The two front limb connectors 12 are connected respectively to the front limb connecting holes 112, and the two hind limb connectors 13 are connected respectively to the hind limb connecting holes 113. In this embodiment, as shown in FIG. 4, a plurality of waterproof sealing rings (R) are sleeved on the front limb connectors 12 and the hind limb connectors 13 so that the front limb connectors 12 are connected sealingly to the front limb connecting holes 112, and so that the hind limb connectors 13 are connected sealingly to the hind limb connecting holes 113.

In this embodiment, the waterproof casing 11 consists of a lower casing 11a and an upper cover 11b. In other embodiments, the waterproof casing 11 may consist of a left half and a right half, and the present disclosure is not limited in this respect.

The waterproof space 111 has a main accommodating chamber 111a, two front motor accommodating chambers 111b disposed in front of the main accommodating chamber 111a, and two rear motor accommodating chambers 111c (only one is visible) flanking a rear portion of the main accommodating chamber 111a. The waterproof casing 11 includes a main casing portion 115 defining the main accommodating chamber 111a therein, two front limb motor casing portions 116 formed respectively with the front limb connecting holes 112, and two hind limb motor casing portions 117 formed respectively with the hind limb connecting holes 113 (only one is visible). The main casing portion 115 cooperates with the front limb motor casing portions 116 to define the front motor accommodating chambers 111b. The main casing portion 115 cooperates with the hind limb motor casing portions 117 to define the rear motor accommodating chambers 111c.

The decorative cover 2 encloses the waterproof housing unit 1, emulates an appearance of a turtle, and includes an upper half 21 and a lower half 22 disposed under the upper half 21.

The control unit 3 is mounted in the main accommodating chamber 111a of the waterproof space 111 of the waterproof casing 11, and is configured to control the front limb driving motors 4 and the hind limb driving motors 5. In this embodiment, the control unit 3 includes two control circuit boards 31.

The two front limb driving motors 4 are disposed in the waterproof space 111, and are electrically connected to the control unit 3 to be controlled thereby. Each of the front limb driving motors 4 includes a front motor body 41, and a front limb driving shaft 42 connected to and driving a respective one of the front limb connectors 12 to rotate about a first front rotating axis (AF1) extending in a front-rear direction. The front motor bodies 41 of the front limb driving motors 4 are accommodated respectively in the front motor accommodating chambers 111b.

The two hind limb driving motors 5 are disposed in the waterproof space 111, and are electrically connected to the control unit 3 to be controlled thereby. Each of the hind limb driving motors 5 includes a rear motor body 51 and a hind limb driving shaft 52 connected to and driving a respective one of the hind limb connectors 13 to rotate about a rear rotating axis (AR) extending in a transverse direction that is perpendicular to the front-rear direction.

The two front limb modules 6 are connected respectively and detachably to the two front limb connectors 12 through a plurality of bolts(S) and washers (G), and are driven respectively by the two front limb driving motors 4 via the two front limb connectors 12. Each of the front limb modules 6 includes an L-shaped link rod 61, a front limb 62, and an angle limiting mechanism 63. For each of the front limb modules 6, the L-shaped link rod 61 has a first segment 611 mounted to a front portion of the respective one of the front limb connectors 12 and extending away from the first segment 611 of the L-shaped link rod 61 of another one of the front limb modules 6, and a second segment 612 extending forwardly from a distal end of the first segment 611 in the front-rear direction. For each of the front limb modules 6, the front limb 62 is mounted to and covers a front portion of the second segment 612 of the L-shaped link rod 61, extends away from the front limb 62 of the another one of the front limb modules 6, and is rotatable about a second front rotating axis (AF2) that extends in the transverse direction and that is perpendicular to the first front rotating axis (AF1), such that the front limb 62 sways upwardly and downwardly during rotation thereof and is subjected to a resistance by the water to propel. In this embodiment, the front limb 62 of each of the front limb modules 6 includes a front limb frame 621 mounted to the front portion of the second segment 612 of the L-shaped link rod 61, and a deformable front flipper portion 622 surrounding and covering the front limb frame 621, and extending rearwardly and away from the deformable front flipper portion 622 of another one of the front limb modules 6. The deformable front flipper portion 622 of each of the front limb modules 6 is made of a polymer material such as silicone, rubber, and other flexible materials.

For each of the front limb modules 6, the angle limiting mechanism 63 is mounted between the L-shaped link rod 61 and the front limb 62 for limiting a rotation angle of the front limb 62 relative to the second segment 612 of the L-shaped link rod 61. The angle limiting mechanism 63 has an arcuate sliding groove 631 and a sliding protrusion 632 slidably engaging the arcuate sliding groove 631. In this embodiment, for each of the front limb modules 6, the sliding protrusion 632 is formed on the second segment 612 of the L-shaped link rod 61, and the arcuate sliding groove 631 is formed in the front limb frame 621 of the front limb 62. In other embodiments, for each of the front limb modules 6, the sliding protrusion 632 may be formed on the front limb frame 621 of the front limb 62, and the arcuate sliding groove 631 may be formed in the second segment 612 of the L-shaped link rod 61, and the structure of the angle limiting mechanism 63 is not limited to the example described herein as long as the angle limiting mechanism 63 is capable of limiting a rotation angle of the front limb 62 relative to the second segment 612 of the L-shaped link rod 61.

The two hind limb modules 7 are connected respectively and detachably to the two hind limb connectors 13 through a plurality of bolts(S) and washers (G) (only one bolt(S) and one washer (G) are visible in FIG. 3), and are driven respectively by the two hind limb driving motors 5 via the two hind limb connectors 13. Each of the hind limb modules 7 includes a hind limb link rod 71 extending in a direction that is parallel to the transverse direction and mounted to a rear portion of the respective one of the hind limb connectors 13, and a deformable hind flipper 72 mounted to and covering a rear portion of the hind limb link rod 71 and extending rearwardly in the front-rear direction. The deformable hind flipper 72 of each of the hind limb modules 7 is made of a polymer material such as silicone, rubber, and other flexible materials.

Since the deformable front flipper portions 622 of the two front limb modules 6 and the deformable hind flippers 72 of the two hind limb modules 7 are made of flexible materials, an appearance of the front limb modules 6 and the hind limb modules 7 looks more nature. Specifically, each of the deformable front flipper portions 622 has a front portion and a rear portion having a thickness smaller than a thickness of the front portion, and an inner portion and an outer portion having a thickness smaller than a thickness of the inner portion. Each of the deformable hind flippers 72 has a front portion and a rear portion having a thickness smaller than a thickness of the front portion.

By virtue of the materials and configurations of the deformable front flipper portions 622 and the deformable hind flippers 72, the rear portion and the outer portion of each of the deformable front flipper portions 622 and the rear portion of each of the deformable hind flippers 72 are deformed and bent when subjected to a resistance by the water during the front limb modules 6 and the hind limb modules 7 swaying in the water to thereby emulate the appearance and swimming motions of a turtle in the water. In addition, for each of the front limb modules 6, since the front limb 62 is rotatable about the second front rotating axis (AF2) and the L-shaped link rod 61 is rotatable about the first front rotating axis (AF1), movement of the biomimetic turtle 100 may be relatively flexible and variable.

Moreover, it should be noted that, although in this embodiment, some portions of each of the two front limb modules 6 and the two hind limb modules 7 are made of a flexible and deformable material, the two front limb modules 6 and the two hind limb modules 7 may be made of a rigid material depending on demands, but are not limited thereto.

Since the two front limb driving motors 4, the two hind limb driving motors 5, and the control unit 3 are all disposed in the waterproof space 111 of the waterproof casing 11, an overall mechanical design of the biomimetic turtle 100 may be simplified, and ordinary motors without a waterproof function may be employed as the two front limb driving motors 4 and the two hind limb driving motors 5.

Furthermore, since each of the two front limb modules 6 and the two hind limb modules 7 is driven by only one motor, the two front limb modules 6 are connected respectively and detachably to the front limb connectors 12, and the two hind limb modules 7 are connected respectively and detachably to the two hind limb connectors 13, the two front limb modules 6 and the two hind limb modules 7 may be quickly replaced to facilitate modification of an appearance of the biomimetic turtle 100 and maintenance of the same.

Referring to FIGS. 4 to 6, the weight module 8 is disposed in the main accommodating chamber 111a of the waterproof space 111 of the waterproof casing 11. The weight module 8 includes a weight member 81 slidable relative to the waterproof casing 11 along a longitudinal axis extending in the front-rear direction, a weight member driving motor 82 mounted to the waterproof casing 11, and a crank connecting mechanism 83 connected between the weight member 81 and the weight member driving motor 82.

In this embodiment, the weight member 81 is a battery unit. In other embodiments, the weight member 81 may be other components having a weight and being capable of changing a center of gravity of the biomimetic turtle 100, and is not limited to the example disclosed herein. As shown in FIG. 5, the waterproof casing 11 is formed with a pair of sliding grooves 118 and the weight member 81 has a pair of sliding ribs 811 slidably and respectively engaging the sliding grooves 118 in order to allow the weight member 81 to slide forwardly and rearwardly relative to the waterproof casing 11, thereby changing a position of the center of gravity of the biomimetic turtle 100. In this way, when the weight module 8 cooperates with the movement of the two front limb modules 6 and the two hind limb modules 7, the biomimetic turtle 100 is controlled to ascend or descend in the water.

The weight member driving motor 82 includes a weight driving shaft 821 rotatable about an upright axis that is perpendicular to the front-rear direction and the transverse direction, and connected co-movably to the crank connecting mechanism 83 for driving movement of the weight member 81. The crank connecting mechanism 83 includes a first rod 831 connected to the weight driving shaft 821 and a second rod 832 connected between the first rod 831 and the weight member 81. The control unit 3 is configured to control the weight member driving motor 82 to drive the movement of the weight member 81 via the crank connecting mechanism 83.

The head module 9 extends through the head connecting hole 114 and is connected to the weight member 81. The head module 9 includes a connecting rod 91 extending through the head connecting hole 114 and connected to the weight member 81, a head casing 92 opening rearwardly and including a connecting bracket 921, and a dual shaft motor 93 connected between the connecting rod 91 and the head casing 92 and driving the head casing 92 to rotate relative to the connecting rod 91. In this embodiment, the connecting rod 91 is hollow and permits extension of electrical wires (not shown) therethrough.

As shown in FIGS. 5 and 6, the dual shaft motor 93 includes a first rotating shaft 931 extending in the transverse direction and connected to the connecting rod 91, and a second rotating shaft 932 extending in a direction parallel to the upright axis and connected to the connecting bracket 921 of the head casing 92. By virtue of the structure of the first rotating shaft 931 and the second rotating shaft 932, the head casing 92 may swing upward, downward, leftward, and rightward relative to the connecting rod 91. In addition, since the connecting rod 91 is connected to the weight member 81 that is slidable relative to the waterproof casing 11, the head casing 92 is co-movable forward and rearward with the weight member 81 to extend and retract relative to the waterproof casing 11.

The waterproof cover 14 is mounted between the head module 9 and the waterproof casing 11, and cooperates with the head casing 92 to define a head space 94 for accommodating the dual shaft motor 93 therein. By virtue of the waterproof cover 14, sea water or fresh water may be prevented from entering the head space 94 or entering the waterproof space 111 through the head connecting hole 114. Furthermore, the waterproof cover 14 is made of a flexible and deformable waterproof material such as silicone or rubber, and has a folded portion 141 that is extendable to accommodate the connecting rod 91 during movement of the weight member 81 relative to the waterproof casing 11 and facilitate swing of the head casing 92.

In addition, it should be noted that, as shown in FIG. 6, two anti-loosening structures (AL) are disposed between the waterproof cover 14 and the head module 9, and between the waterproof cover 14 and the waterproof casing 11, respectively. One of the anti-loosening structure (AL) disposed between the waterproof cover 14 and the head module 9 has a concave-convex fitting engaging structure, and another one of the anti-loosening structures (AL) disposed between the waterproof cover 14 and the waterproof casing 11 has an interference fitting structure, which includes a protrusion (not shown) extending from the waterproof casing 11 into and engaging the waterproof cover 14. Furthermore, an anti-loosening ring 15 is sleeved on the waterproof cover 14 and clamps the waterproof casing 11 and the waterproof cover 14 therebetween to prevent the waterproof cover 14 from falling off. It should be noted that, in other embodiments, another anti-loosening ring may be disposed between the waterproof cover 14 and the head module 9.

In addition, as shown in FIG. 5, the biomimetic turtle 100 further includes a plurality of infrared sensors (IS) disposed in the main accommodating chamber 111a of the waterproof space 111 and the head space 94, and electrically connected to the control unit 3. The infrared sensors (IS) respectively output, to the control unit 3, a plurality of distance signals each indicating a distance between the respective one of the infrared sensors (IS) and an object sensed thereby. When at least one of the distance signals satisfies a certain criteria, e.g., the distance between the respective one of the infrared sensors (IS) and an object sensed thereby is smaller than a predetermined value, the control unit 3 controls the front limb driving motors 4 and the hind limb driving motors to move the biomimetic turtle 100 away from the object, thus preventing the biomimetic turtle 100 from hitting an obstacle, i.e., the object, therearound. It should be noted that the control unit 3 may include a microcontroller or a controller such as, but not limited to, a single core processor, a multi-core processor, a dual-core mobile processor, a microprocessor, a microcontroller, a digital signal processor (DSP), a field-programmable gate array (FPGA), an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), etc.

To sum up, in the present disclosure, since the two front limb driving motors 4, the two hind limb driving motors 5, and the control unit 3 are all disposed in the waterproof space 111 of the waterproof casing 11, an overall mechanical design of the biomimetic turtle 100 may be simplified while a waterproof motor is not employed. Additionally, since each of the two front limb modules 6 and the two hind limb modules 7 is driven by only one motor, the two front limb modules 6 are connected respectively and detachably to the front limb connectors 12, and the two hind limb modules 7 are connected respectively and detachably to the two hind limb connectors 13, the two front limb modules 6 and the two hind limb modules 7 may be easily and quickly replaced to facilitate modification of an appearance of the biomimetic turtle 100 and maintenance of the same.

In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiment(s). It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means in that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects; such does not mean that every one of these features needs to be practiced with the presence of all the other features. In other words, in any described embodiment, when implementation of one or more features or specific details does not affect implementation of another one or more features or specific details, said one or more features may be singled out and practiced alone without said another one or more features or specific details. It should be further noted that one or more features or specific details from one embodiment may be practiced together with one or more features or specific details from another embodiment, where appropriate, in the practice of the disclosure.

While the disclosure has been described in connection with what is (are) considered the exemplary embodiment(s), it is understood that this disclosure is not limited to the disclosed embodiment(s) but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

Claims

1. A biomimetic turtle, comprising: a waterproof housing unit that includes a waterproof casing defining a waterproof space therein, and having two front limb connecting holes that are in fluid communication with said waterproof space, andtwo hind limb connecting holes that are in fluid communication with said waterproof space,two front limb connectors connected respectively to said front limb connecting holes, andtwo hind limb connectors connected respectively to said hind limb connecting holes;two front limb driving motors that are disposed in said waterproof space, each of said front limb driving motors including a front limb driving shaft that is connected to a respective one of said front limb connectors;two hind limb driving motors that are disposed in said waterproof space, each of said hind limb driving motors including a hind limb driving shaft that is connected to a respective one of said hind limb connectors;two front limb modules that are connected respectively and detachably to said front limb connectors, and that are driven respectively by said front limb driving motors via said front limb connectors;two hind limb modules that are connected respectively and detachably to said hind limb connectors, and that are driven respectively by said hind limb driving motors via said hind limb connectors; anda control unit that is mounted in said waterproof space of said waterproof casing, and that is configured to control said front limb driving motors and said hind limb driving motors.

2. The biomimetic turtle of claim 1, wherein: each of said front limb driving motors further includes a front motor body;each of said hind limb driving motors further includes a rear motor body;said waterproof space has two front motor accommodating chambers accommodating respectively said front motor bodies of said front limb driving motors, andtwo rear motor accommodating chambers accommodating respectively said rear motor bodies of said hind limb driving motors; andsaid waterproof casing includes a main casing portion,two front limb motor casing portions formed respectively with said front limb connecting holes, and cooperating with said main casing portion to define said front motor accommodating chambers, andtwo hind limb motor casing portions formed respectively with said hind limb connecting holes, and cooperating with said main casing portion to define said rear motor accommodating chambers.

3. The biomimetic turtle of claim 1, wherein: said biomimetic turtle further comprises: a weight module disposed in said waterproof space and including a weight member that is slidable relative to said waterproof casing along a longitudinal axis extending in a front-rear direction,a weight member driving motor that is mounted to said waterproof casing, anda crank connecting mechanism that is connected between said weight member and said weight member driving motor; andsaid control unit is configured to control said weight member driving motor to drive movement of said weight member via said crank connecting mechanism.

4. The biomimetic turtle of claim 3, wherein said weight member is a battery unit.

5. The biomimetic turtle of claim 3, wherein said weight member driving motor includes a weight driving shaft rotatable about an upright axis perpendicular to the front-rear direction, and connected co-movably to said crank connecting mechanism for driving the movement of said weight member.

6. The biomimetic turtle of claim 3, wherein: said waterproof casing further has a head connecting hole in fluid communication with said waterproof space;said biomimetic turtle further comprises a head module extending through said head connecting hole and connected to said weight member; andsaid waterproof housing unit further includes a waterproof cover mounted between said head module and said waterproof casing.

7. The biomimetic turtle of claim 6, wherein: said head module includes a connecting rod extending through said head connecting hole and connected to said weight member,a head casing opening rearwardly in the front-rear direction, anda dual shaft motor connected between said connecting rod and said head casing, and driving said head casing to rotate relative to said connecting rod; andsaid waterproof cover cooperates with said head casing to define a head space for accommodating said dual shaft motor therein.

8. The biomimetic turtle of claim 1, wherein: each of said front limb connectors is rotatable about a first front rotating axis extending in a front-rear direction; andeach of said front limb modules includes an L-shaped link rod having a first segment that is mounted to a front portion of the respective one of said front limb connectors and that extends away from said first segment of said L-shaped link rod of another one of said front limb modules, anda second segment that extends forwardly from a distal end of said first segment in the front-rear direction, anda front limb mounted to and covering a front portion of said second segment, extending away from said front limb of said another one of said front limb modules, and rotatable about a second front rotating axis that is perpendicular to the first front rotating axis.

9. The biomimetic turtle of claim 8, wherein: each of said front limb modules further includes an angle limiting mechanism mounted between said L-shaped link rod and said front limb for limiting a rotation angle of said front limb relative to said second segment of said L-shaped link rod; andsaid angle limiting mechanism has an arcuate sliding groove formed in one of said L-shaped link rod and said front limb, anda sliding protrusion slidably engaging said arcuate sliding groove and formed on another one of said L-shaped link rod and said front limb.

10. The biomimetic turtle of claim 8, wherein said front limb of each of said front limb modules includes a front limb frame mounted to the front portion of said second segment of said L-shaped link rod, anda deformable front flipper portion surrounding and covering said front limb frame, and extending rearwardly away from said deformable front flipper portion of another one of said front limb modules.

11. The biomimetic turtle of claim 1, wherein: each of said hind limb connectors is rotatable about a rear rotating axis extending in a transverse direction; andeach of said hind limb modules includes a hind limb link rod extending in a direction parallel to the transverse direction, and mounted to a rear portion of the respective one of said hind limb connectors, anda deformable hind flipper mounted to and covering a rear portion of said hind limb link rod and extending rearwardly in the front-rear direction.