Multi-degree of freedom thumb mechanism

Abstract

The application provides a multi-degree-of-freedom thumb mechanism, which comprises a thumb body, a first driving part, a second driving part and a third driving part, and a base; the thumb body comprises a first finger segment, a second finger segment and a third finger segment connected in sequence; the first driving part drives the first finger segment to bend and stretch; the second driving part drives the second finger segment to bend and stretch; the third driving part drives the third finger segment to rotate; the base integrates the first driving part, the second driving part and the third driving part at the end of the third finger segment; the first driving part and the second driving part adopt a coaxial design to realize the control of the first finger segment and the second finger segment. The thumb mechanism has multiple degrees of freedom; the coaxial design of the first driving part and the second driving part improves the flexibility of the fingers and increases the driving power device, and avoids the increase of the volume of the whole robot hand.

Description

Technical Field

[0001] The present invention relates to the field of manipulators, and in particular to a multi-degree-of-freedom thumb mechanism. Background Art

[0002] As a key component of a robot's end effector, robotic fingers play a crucial role in improving the overall performance of robotic systems through their gripping capabilities, operational precision, and reliability. This is particularly true for dexterous robotic hands designed to mimic the functions of human hands. Despite continuous technological advancements, existing robotic hands are often limited by their low flexibility, making them incapable of handling complex and diverse tasks.

[0003] It's worth noting that while increasing the degrees of freedom of individual fingers improves their flexibility, it also increases the complexity of the drive system, leading to an increase in the overall size of the robotic hand. This increase in size not only increases manufacturing costs but also potentially restricts the robot hand's applicability in confined spaces or specific environments, limiting its wide range of practical applications. Summary of the Invention

[0004] In view of the defects in the prior art, an object of the present invention is to provide a multi-degree-of-freedom thumb mechanism.

[0005] According to one aspect of the present invention, there is provided a multi-degree-of-freedom thumb mechanism, comprising:

[0006] A thumb body, the thumb body comprising a first finger segment, a second finger segment and a third finger segment connected in sequence;

[0007] a first driving unit, the first driving unit driving the first finger segment to bend and extend;

[0008] a second driving unit, the second driving unit driving the second finger segment to bend and extend;

[0009] a third driving unit, which drives the third finger segment to rotate, thereby driving the first finger segment and the second finger segment to rotate;

[0010] a base, wherein the base integrates the first driving unit, the second driving unit, and the third driving unit at the end of the third finger segment;

[0011] The first driving unit and the second driving unit are coaxially designed to achieve independent control of the first finger segment and the second finger segment.

[0012] Preferably, the first finger segment and the second finger segment are hinged with a first movement axis; the second finger segment and the third finger segment are hinged with a second movement axis.

[0013] Preferably, the first driving part and the second driving part adopt a coaxial design, specifically:

[0014] The first driving unit includes:

[0015] a first motor, wherein the first motor is fixed to the lower surface of the base;

[0016] a first worm, the first worm being disposed on the upper surface of the base and connected to the output shaft of the first motor;

[0017] a first worm gear meshing with the first worm;

[0018] a first rotating shaft, the first rotating shaft being inserted into the first worm gear;

[0019] a transition sleeve, the transition sleeve being between the first rotating shaft and the first worm gear; the transition sleeve does not rotate due to the rotation of the first rotating shaft;

[0020] a first capstan, the first capstan being sleeved on the first rotating shaft;

[0021] a first steel wire rope, wherein the first steel wire rope drum is provided on the first winch and extends outward until it is connected to the first finger segment;

[0022] The second driving unit includes:

[0023] a second motor, the second motor being fixed to the lower surface of the base;

[0024] a second worm, the second worm being disposed on the upper surface of the base and connected to the output shaft of the second motor;

[0025] a second worm gear, the second worm gear being sleeved on the first rotating shaft and meshing with the second worm;

[0026] a second capstan, the second capstan being disposed at an end of the first rotating shaft and adjacent to the first capstan;

[0027] The second steel wire rope is arranged on the second winch and extends outward until it is connected with the second finger segment.

[0028] Preferably, it also includes multiple guide wheels, and the first steel wire rope runs along each guide wheel, bypasses the first motion axis and transitions to connect with the first finger segment, and the first steel wire rope directly drives the first finger segment to rotate; the second steel wire rope runs along the guide wheel and is connected to the second motion axis through a sleeve.

[0029] Preferably, the first worm gear and the first rotating shaft are fixed via a transition sleeve; the first worm gear and the first capstan are designed as one body.

[0030] Preferably, the first motor is started to drive the first worm to rotate, thereby driving the first worm wheel to rotate and the first capstan to rotate on the transition sleeve at the same time, thereby driving the first steel wire rope, while the first rotating shaft remains unaffected and maintains its original state;

[0031] The second motor is started to drive the second worm to rotate, thereby driving the second worm wheel, the first rotating shaft and the second capstan to rotate together, thereby driving the second steel wire rope to move.

[0032] Preferably, the device further comprises a housing for fixing the first rotating shaft.

[0033] Preferably, the third driving unit includes:

[0034] a third drive shaft connected to the third finger segment and maintaining the same axial direction therewith;

[0035] a third worm gear fixed to a distal end of the third drive shaft;

[0036] a third motor, the third motor being fixed to the lower surface of the base;

[0037] A third worm is arranged on the upper surface of the base, is connected to the output shaft of the third motor, and is meshed with the third worm wheel.

[0038] Preferably, the third drive shaft is a hollow shaft, and the first steel wire rope and the second steel wire rope pass through the third drive shaft.

[0039] Preferably, when the first finger segment, the second finger segment and the third finger segment move synchronously, the third driving part has no effect on the first steel wire rope and the second steel wire rope.

[0040] Compared with the prior art, the embodiments of the present invention have at least one of the following beneficial effects:

[0041] A multi-degree-of-freedom thumb mechanism in an embodiment of the present invention has multiple degrees of freedom; and the first drive part and the second drive part adopt a coaxial design, which improves the flexibility of the fingers and increases the driving power device while avoiding an increase in the volume of the entire robot hand.

[0042] A multi-degree-of-freedom thumb mechanism in an embodiment of the present invention is driven by multiple steel wires and worm gears. Through clever arrangement, the finger's grasping ability, operating ability, reliability and flexibility are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0044] Figure 1 2 is a schematic structural diagram of a multi-degree-of-freedom thumb mechanism according to an embodiment of the present invention;

[0045] Figure 2 A side view of a multi-degree-of-freedom thumb mechanism according to an embodiment of the present invention;

[0046] Figure 3 A cross-sectional view showing the connection relationship between the first driving portion and the second driving portion in a preferred embodiment of the present invention;

[0047] Figure 4 A diagram showing the connection relationship between the second worm gear and the first rotating shaft in a preferred embodiment of the present invention;

[0048] Figure 5 is an overall cross-sectional view of a multi-degree-of-freedom thumb mechanism in a preferred embodiment of the present invention;

[0049] Figure 6 For Figure 5 The corresponding overall cross-sectional view from another perspective.

[0050] In the figure: 1-first finger segment, 2-second finger segment, 3-third drive shaft, 4-third worm, 5-second worm, 6-second worm wheel, 7-first rotating shaft, 8-first worm wheel, 9-first capstan, 10-second capstan, 11-first worm, 12-first motor, 13-third worm wheel, 14-third motor, 15-third finger segment, 16-base, 17-second motor, 18-housing, 19-transition sleeve. DETAILED DESCRIPTION

[0051] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0052] like Figure 1 and Figure 2As shown, in one embodiment of the present invention, a multi-degree-of-freedom thumb mechanism is provided, the structure of which mainly includes a thumb body, a first drive unit, a second drive unit, a third drive unit, and a base 16. The thumb body includes a first finger segment 1, a second finger segment 2, and a third finger segment 15 connected in sequence; the first drive unit drives the first finger segment 1 to bend and extend; the second drive unit drives the second finger segment 2 to bend and extend; and the third drive unit drives the third finger segment 15 to rotate, thereby driving the first and second finger segments to rotate. The base 16 integrates the first, second, and third drive units at the end of the third finger segment. The first and second drive units are coaxial in design, enabling independent control of the first and second finger segments 1 and 2.

[0053] The multi-degree-of-freedom thumb mechanism in the above embodiment has multiple degrees of freedom; and the first drive part and the second drive part adopt a coaxial design, which improves the flexibility of the fingers and increases the driving power device while avoiding an increase in the size of the entire robot hand.

[0054] In a preferred embodiment of the present invention, the first finger segment 1 and the second finger segment 2 are hinged by a first motion axis; the second finger segment 2 and the third finger segment 15 are hinged by a second motion axis.

[0055] In a preferred embodiment of the present invention, a preferred solution for the coaxial design of the first driving part and the second driving part is provided. The details are as follows:

[0056] The first drive unit includes a first motor 12, a first worm 11, a first worm wheel 8, a first capstan 9, a first rotating shaft 7, and a first wire rope. The first motor 12 is fixed to the lower surface of the base 16, and its output shaft extends upward. The first worm 11 is sleeved on the outside of the output shaft. The first worm wheel 8 meshes with the first worm 11. The first rotating shaft 7 is inserted into the interior of the first worm wheel 8. The first capstan 9 is mounted on the first rotating shaft 7. The first wire rope drum is mounted on the first capstan 9 and extends outward until it connects with the first finger segment 1.

[0057] Similarly, the second drive unit includes a second motor 17, a second worm 5, a second worm wheel 6, a second capstan 10 and a second wire rope. The second drive unit is coaxial with the first drive unit, which mainly includes two aspects. One is that the worm wheels of the two drive units are coaxial, and the other is that the capstans of the two drive units are coaxial, so as to ensure that the two ropes are arranged compactly. Specifically, the second motor 17 is fixed to the lower surface of the base 16, and its output shaft extends upward. The second worm 5 is sleeved on the outside of the output shaft. The second worm wheel 6 is engaged with the second worm 5. The second worm 6 is sleeved on the outside of the first rotating shaft 7. The second capstan 10 is arranged at the end of the first rotating shaft 7 and is adjacent to the first capstan 9. The second wire rope drum is arranged on the second capstan and extends outward until it is connected to the second finger segment;

[0058] In order to achieve more flexible and precise control of the first finger segment or the second finger segment by the wire rope, in a preferred embodiment, Figure 5 and Figure 6 As shown, bushings are installed outside the first and second motion shafts. Additionally, a right guide wheel is installed inside the third finger segment, and a left guide wheel is installed inside the second finger segment. A first pull rope extends outward from the first capstan, passing around the right guide wheel, the second motion shaft, the left guide wheel, and the first motion shaft, before being fixedly connected to the first finger segment. The first pull rope directly drives the first finger segment to rotate around the first motion shaft. A second pull rope extends outward from the first capstan, passing around the right guide wheel, and is fixed to the bushing of the second motion shaft.

[0059] It should be noted that the second steel wire rope is wound around the same side of the second motion axis from the right guide wheel side; the first steel wire rope is wound around the other side of the second motion axis from the right guide wheel side. Figure 5 and Figure 6 It is shown that the first steel wire rope is S-shaped at the second motion axis and the right guide wheel, and the second steel wire rope is semi-elliptical at the second motion axis and the right guide wheel. Usually, the rotation of the second drive unit will affect the first drive unit. This is a coupling effect. When the second drive unit rotates, the first drive motor will work relatively to ensure that the rotation of the second drive unit does not affect the first drive unit. Through the above structural design, when the second drive unit drives the second finger segment to contract, the first drive unit needs to relax the first finger segment to offset the influence of the second drive. When the second drive unit drives the second finger segment to relax, the first drive unit needs to contract the first finger segment to offset the influence of the second drive.

[0060] To further enable flexible control of the first and second finger segments, in a preferred embodiment, a transition sleeve 19 is installed between the first worm gear 8 and the first rotating shaft 7. The first worm gear 8 and the first capstan 9 are integrated. The first worm gear 8 and the first capstan 9 rotate on the transition sleeve 19 without affecting the state of the first rotating shaft 7.

[0061] The second worm gear 6 is fixed to the first rotating shaft 7, and the second capstan 10 is fixed to the first rotating shaft 7. In some specific embodiments, Figure 3 and Figure 4 As shown, the second worm gear 10 and the first rotating shaft are connected by a T-type link, and the first rotating shaft 7 and the second capstan 10 are connected by a D-type shaft, so that torque can be transmitted.

[0062] Based on the structural design in the above embodiments, in a preferred embodiment of the present invention, the first drive unit and the second drive unit are operated, specifically: the first motor 12 is started, and its output shaft rotates, driving the first worm 11 to rotate, and the transmission causes the first worm wheel 8 to rotate, driving the first capstan 9 to rotate, thereby moving the first wire rope.

[0063] The second motor 17 is started, and its output shaft rotates, driving the second worm 5 to rotate, which in turn causes the second worm wheel 6 to rotate, driving the first rotating shaft 7 and the second capstan 10 to rotate simultaneously, thereby moving the second steel wire rope.

[0064] In some specific embodiments, a housing 18 is additionally installed, and the housing 18 mainly provides a fixing function for the first rotating shaft 7, the first worm gear 8, the second worm gear 6, etc.

[0065] The degree of freedom of the third finger segment is different from that of the first finger segment and the second finger segment. In order to enable the first finger segment, the second finger end and the third finger segment to move synchronously as a whole, a preferred method of the third driving unit is provided in a preferred embodiment of the present invention. Specifically, the third driving unit includes a third driving shaft 3, a third motor 14, a third worm 4 and a third worm gear 13. The third driving shaft 3 is connected to the third finger segment 15. The direction of the third driving shaft 3 is perpendicular to the direction of the first motion axis and the second motion axis, that is, the third motion shaft 3 maintains a coaxial relationship with the third finger segment. The third worm gear 13 is arranged at the end of the third driving shaft. The third motor 14 is also arranged on the lower surface of the base 16, and its output shaft is also connected to the third worm 4, and the third worm 4 is engaged with the third worm gear 13.

[0066] When the third finger segment needs to rotate, the third motor 14 is started to drive the third worm 4 to rotate, and the transmission causes the third worm wheel 13 to rotate, driving the third drive shaft 3 to rotate, thereby causing the third finger segment to rotate, that is, the entire thumb body rotates synchronously.

[0067] In a preferred embodiment, the third drive shaft 3 is configured as a hollow shaft so that the first steel wire rope and the second steel wire rope pass through it, ensuring that when the third drive shaft 13 drives the three finger segments to move together, the impact on the spatial position of the first steel wire rope and the second steel wire rope is reduced.

[0068] The above embodiment uses multiple steel wires and worm gear drives, and through clever arrangement, the finger gripping ability, operating ability, reliability and flexibility are improved.

[0069] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various modifications or variations within the scope of the claims without affecting the essence of the present invention. The above preferred features may be used in any combination as long as they do not conflict with each other.

Claims

1. A multi-degree-of-freedom thumb mechanism, characterized in that: include: A thumb body, the thumb body comprising a first finger segment, a second finger segment and a third finger segment connected in sequence; a first driving unit, the first driving unit driving the first finger segment to bend and extend; a second driving unit, the second driving unit driving the second finger segment to bend and extend; a third driving unit, which drives the third finger segment to rotate, thereby driving the first finger segment and the second finger segment to rotate; a base, wherein the base integrates the first driving unit, the second driving unit, and the third driving unit at the end of the third finger segment; The first driving part and the second driving part adopt a coaxial design, the worm gears of the two driving parts are coaxial, and the capstans of the two driving parts are coaxial, so as to realize independent control of the first finger segment and the second finger segment; The first driving part includes a first steel wire rope, and the second driving part includes a second steel wire rope; The third driving unit includes: a third drive shaft connected to the third finger segment and maintaining the same axial direction therewith; a third worm gear fixed to a distal end of the third drive shaft; a third motor, the third motor being fixed to the lower surface of the base; a third worm, the third worm being arranged on the upper surface of the base, connected to the output shaft of the third motor, and meshing with the third worm wheel; The third drive shaft is a hollow shaft, and the first steel wire rope and the second steel wire rope pass through the third drive shaft.

2. The multi-degree-of-freedom thumb mechanism according to claim 1, characterized in that: The first finger segment and the second finger segment are hinged with a first movement axis; the second finger segment and the third finger segment are hinged with a second movement axis.

3. The multi-degree-of-freedom thumb mechanism according to claim 2, characterized in that: The first driving part and the second driving part adopt a coaxial design, specifically: The first driving unit includes: a first motor, wherein the first motor is fixed to the lower surface of the base; a first worm, the first worm being disposed on the upper surface of the base and connected to the output shaft of the first motor; a first worm gear meshing with the first worm; a first rotating shaft, the first rotating shaft being inserted into the first worm gear; a transition sleeve, the transition sleeve being between the first rotating shaft and the first worm gear and not rotating due to the rotation of the first rotating shaft; a first capstan, the first capstan being sleeved on the first rotating shaft; The first steel wire rope drum is provided on the first winch and extends outward until it is connected to the first finger segment; The second driving unit includes: a second motor, the second motor being fixed to the lower surface of the base; a second worm, the second worm being disposed on the upper surface of the base and connected to the output shaft of the second motor; a second worm gear, the second worm gear being sleeved on the first rotating shaft and meshing with the second worm; a second capstan, the second capstan being disposed at an end of the first rotating shaft and adjacent to the first capstan; The second steel wire rope drum is arranged on the second winch and extends outward until it is connected with the second finger segment.

4. The multi-degree-of-freedom thumb mechanism according to claim 3, characterized in that: It also includes multiple guide wheels, and the first steel wire rope runs along each guide wheel, bypasses the first motion axis and transitions to connect with the first finger segment, and the first steel wire rope directly drives the first finger segment to rotate; the second steel wire rope runs along the guide wheel and is connected to the second motion axis through a shaft sleeve.

5. The multi-degree-of-freedom thumb mechanism according to claim 3, characterized in that: The first worm gear and the first rotating shaft are concentrically mounted via a transition sleeve, and the first worm gear and the first capstan are designed as an integral whole.

6. The multi-degree-of-freedom thumb mechanism according to claim 5, characterized in that: The first motor is started to drive the first worm to rotate, thereby driving the first worm wheel and the first capstan to rotate on the transition sleeve, thereby driving the first steel wire rope, while the first rotating shaft remains unaffected and maintains its original state; The second motor is started to drive the second worm to rotate, thereby driving the second worm wheel, the first rotating shaft and the second capstan to rotate together, thereby driving the second steel wire rope to move.

7. The multi-degree-of-freedom thumb mechanism according to claim 6, characterized in that: It also includes a housing for fixing the first rotating shaft.

8. The multi-degree-of-freedom thumb mechanism according to claim 1, characterized in that: When the first finger segment, the second finger segment and the third finger segment move synchronously, the third driving unit has no effect on the first steel wire rope and the second steel wire rope.

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