WO2020046214A1

WO2020046214A1 - Robotic arm, minimal invasive surgery robot, and respective manufacturing method thereof

Info

Publication number: WO2020046214A1
Application number: PCT/SG2019/050435
Authority: WO
Inventors: Hongliang REN; Changsheng Li; Xiaoyi GU; Xiao Xiao; Chwee Ming LIM
Original assignee: National University Of Singapore; National University Of Singapore Suzhou Research Institute; National University Hospital (Singapore) Pte Ltd
Priority date: 2018-08-31
Filing date: 2019-09-02
Publication date: 2020-03-05
Also published as: CN110870793A; CN110870793B

Abstract

A robotic arm includes a frame unit; a motion unit comprising elastic rods and a stiffness adjustment unit comprising hollow stiffness adjustment tubes. The motion unit and the stiffness adjustment unit are supported by the frame unit. The elastic rods are operatively movable along a longitude direction of the frame unit. The stiffness adjustment tubes are adapted to surround a first segment of the elastic rod, and be operatively movable along the longitude direction to vary a length of a second segment of the elastic rod at a first end away from the frame unit and not surrounded by the stiffness adjustment tubes, to adjust the stiffness of the first end of the elastic rod. The robotic arm and the robot enable real time adjustment of the stiffness of the distal end of the robotic arm to meet different surgery operations' requirements and improve the safety of the surgery operations.

Description

ROBOTIC ARM, MINIMAL INVASIVE SURGERY ROBOT, AND RESPECTIVE MANUFACTURING METHOD THEREOF

TECHNICAL FIELD

Embodiments of the present disclosure relates to a robotic arm and a robot for minimal invasive surgery, and in particular relates to a robotic arm and a robot for laryngopharyngeal surgery and respective manufacturing method thereof.

BACKGROUND

Traditional laryngopharyngeal surgery is mainly performed through surgical instruments equipped with endoscope. In recent years, with the continuous development in information technologies, control technologies, robotics and related technologies, robot for laryngopharyngeal surgery is gradually developed and applied. Compared with traditional surgical instruments, robot for laryngopharyngeal minimal invasive surgery has significant advantages such as reduction in intraoperative bleeding, postoperative complications and operation time, and so on. However, due the small size, deep location and complex shape of laryngopharynx, higher requirements for such a robot are put forward. The existing robots for laryngopharyngeal have disadvantages such as large size, complex mechanism, control complexity, low level of security, and so on.

SUMMARY

The present invention overcomes the disadvantages in the prior art, and provides a robotic arm with stiffness adjustable in real time, and provides a minimal invasive surgery robot using the robotic arm.

According to a first aspect, the present disclosure provides a robotic arm. The robotic arm comprises a frame unit, a motion unit and a stiffness adjustment unit. The motion unit comprises elastic rods. The motion unit is supported by the frame unit. The elastic rods are configured to be operatively movable along a longitudinal direction of the elastic rod with respect to the frame unit. The stiffness adjustment unit comprises hollow stiffness adjustment tubes. The stiffness adjustment unit is supported by the frame unit. The stiffness adjustment tube is configured to surrounding a first segment of the elastic rod and operatively movable along the longitudinal direction so as to vary a length of a second segment of the elastic rods at a first end of the elastic rods away from the frame unit and not surrounded by the stiffness adjustment tubes, to adjust a stiffness of the first end of the elastic rods.

With embodiments in the present disclosure, the stiffness at one end of the elastic rod can be adjusted in real time, which is very advantageous for performing surgical operations with high precision requirements.

In some embodiments, the frame unit may comprise two stoppers. The motion unit may comprise connection tubes. The connection tubes may be adapted to pass through the two stoppers and be movable along the longitudinal direction relative to the two stoppers. Preferably, the elastic rods can be fixed to the connection tubes. In such manner, the longitudinal movement of the elastic rods can be carried out more stably.

In some embodiments, the motion unit may comprise a lead screw and a lead screw connector through which both the lead screw and the connection tube pass. The connection tube can be fastened to the lead screw connector. Rotation of the lead screws of the motion unit drives the lead screw connector to move along the longitudinal direction. Preferably, the lead screws drive the lead screw connector to move between the two stoppers through threads formed on the lead screw and the lead screw connector. In such manner, the lead screw can be used to transform the rotational motion into linear motion so as to drive the elastic rods more stably and precisely.

In some embodiments, the motion unit may comprise three elastic rods. Each elastic rod can be extended into a corresponding connection tube at a second end of the elastic rod, wherein the second end is adjacent to the frame unit. In this way, each of the three elastic rods can be independently driven to adjust the orientation of a distal end of the robotic arm in three degree of freedom. In other words, the asynchronous movement of the three elastic rods will cause the distal end of the robotic arm to tilt or rotate, while the synchronous movement of the three elastic rods will cause the distal end of the robotic arm to move back and forth. In addition, parallelly arranged, elastic rod-based arrangement has the advantages of high positioning accuracy and large output force.

In some embodiments, the motion unit may comprise three elastic rods. Each elastic rod can be extended into a corresponding connection tube at a second end which is an end of the elastic rod adjacent to the frame unit. Each connection tube can be fastened to a corresponding lead screw connector, and each lead screw connector can be driven by a lead screw of a respective motion unit. Preferably, each elastic rod may be provided with a corresponding universal joint at the first end, and each universal joint may be attached to a flange for transmitting a movement of the elastic rod to the flange along the longitudinal direction. In this way, the distal end of the robotic arm has a universal structure, which can be adapted for mounting surgical instruments as needs, such as forceps, surgical scissors, sintering tools for the throat surgery, and so on.

In some embodiments, the frame unit may include two stoppers. The stiffness adjustment unit may include connection rods. The connection rods may be configured to pass through the two stoppers and be movable along the longitudinal direction relative to the two stoppers. Preferably, the stiffness adjustment tubes are fixed relative to the connection tubes. In this way, the movement of the stiffness adjustment tube in longitudinal direction can be carried out more stably.

In some embodiments, the stiffness adjustment unit may include a stiffness adjustment unit lead screw and a lead screw connector. The stiffness adjustment unit lead screw and the connection rods can pass through the stiffness adjustment unit connector. The connection rods may be fastened to the stiffness adjustment unit connector. The rotation of the stiffness adjustment unit lead screw can drive the stiffness adjustment unit connector to move along the longitudinal direction. Preferably, the stiffness adjustment unit lead screw may drive the stiffness adjustment unit connector between the two stoppers through threads formed on the lead screw and the stiffness adjustment unit connector. In this way, the lead screw can be used to convert rotational motion into linear motion so as to drive the elastic rods more stably and precisely.

In a second aspect, the disclosure provides a minimal invasive surgery robot. The robot includes a robotic arm as illustrated above; a stand for supporting the robotic arm; and an endoscope camera head connected to the stand.

In some embodiments, the robot may include two robotic arms. In this way, the robot can be operated to act on the target with six degree of freedom so as to achieve a better positioning accuracy.

In some embodiments, the stand may include a slot. A base of the frame unit can be fastened to the stand through the slot. In this way, the relative positions of the two arms can be adjusted through the slot.

In some embodiments, the robot may be a minimal invasive laryngopharyngeal surgery robot.

In another aspect, the present disclosure provides a method for manufacturing a robotic arm. The method comprises providing a frame unit, a motion unit and a stiffness adjustment unit. The motion unit comprises elastic rods. The motion unit is supported by the frame unit. The elastic rods are configured to be operably movable along the longitudinal direction of the elastic rod relative to the frame unit. The stiffness adjustment unit comprises hollow stiffness adjustment tubes. The stiffness adjustment unit is supported by the frame unit. The stiffness adjustment tubes are configured to surround a second segment of the elastic rods and operably movable along the longitudinal direction, to vary a length of a first segment of the elastic rod not surrounded by the stiffness adjustment tubes at a first end, and thus to adjust the stiffness of the fist end of the elastic rods, wherein the first end is an end of the elastic rod which is far away from the frame unit

In a further aspect, the disclosure provides a method for manufacturing a robot for minimal invasive surgery. The method comprises providing a robotic arm as described hereinbefore; providing a stand for supporting the robotic arm; and providing an endoscope camera head connected to the stand.

The advantages of the disclosed embodiments generally lie in that the stiffness of the distal end of the robotic arm is adjustable in real time during the operation, meeting different surgical requirements and improving the safety of the operation.

BRIEF DESCRIPTION OF THE DRAWINGS

Through descriptions hereinafter and in conjunction with the accompanying drawings, the present disclosure will be more readily understood. In the drawings, several embodiments are illustrated only for illustration without any intention to limit the scope of the present disclosure, in which:

Figure l is a schematic view of a robotic arm in accordance with an embodiment of the present disclosure;

Figure 2 is a perspective view of a motion unit mounted on a frame unit according to an embodiment of the present disclosure;

Figure 3 is a perspective view of a frame unit in accordance with an embodiment of the present disclosure;

Figure 4 is a perspective view of components in the motion unit mounted to the stoppers in the frame unit which are associated with the driving to elastic rods, according to an embodiment of the present disclosure;

Figure 5 is a perspective view of a lead screw connector, in accordance with an embodiment of the present disclosure;

Figure 6 is a perspective view of a stiffness adjustment unit mounted to the frame unit, in accordance with an embodiment of the present disclosure;

Figure 7 is a perspective view of a lead screw connector, in accordance with an embodiment of the present disclosure;

Figure 8 is a perspective view of a stopper in accordance with an embodiment of the present disclosure;

Figure 9 is a perspective view of a robotic arm in accordance with an embodiment of the present disclosure;

Figure 10 is a perspective view of a stand in accordance with an embodiment of the present disclosure;

Figure 11 is a perspective view of a minimal invasive surgery robot in accordance with an embodiment of the present disclosure;

Figure 12 is a schematic view of a minimal invasive surgery robot during operation on the laryngopharynx, in accordance with an embodiment of the present disclosure;

Figure 13 is a flow chart of a method of manufacturing a robotic arm according to an embodiment of the present disclosure; and

Figure 14 is a flow chart of a method of manufacturing a minimal invasive surgical robot, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

The principle of the present disclosure will now be described with reference to various exemplary embodiments shown in the drawings. It will be appreciated that the descriptions of these embodiments are merely for the purpose of making the present disclosure better understood and enables the present invention to be implemented by those skilled in the art, rather than any intention to limit the scope of the present disclosure. It should be noted that like or same reference numerals refer to identical or functionally similar elements throughout the separate views. It will be readily understood for those skilled in the art that changes may be made to the structure and method described in exemplary embodiments without departing from the principle of the present disclosure.

The terms“include”,“comprise”,“contain” and derivatives thereof should be construed as“including but not limited to”. Unless otherwise indicated, the term“or” should be construed as“and/or”. In addition, the terms“based on”,“on the basis of’, “according to”,“in accordance with” should be construed as“at least partially based on” or “at least partially according to”. The terms “one embodiment” and “embodiments” should be construed as“at least one embodiment”. The term“another embodiment” should be construed as“at least one another embodiment”. Unless otherwise indicated or defined, the terms“mount”,“attach”,“connect”,“support” , “couple” and derivatives thereof should be construed as including both directly and indirectly“mount”,“attach”,“connect”,“support” and“couple”. Further, the terms “connect”, “attach” and “couple” are not limited to physically or mechanically “connect”,“attach” and“couple”.

Figure 1 is a schematic view of a robotic arm 100 in accordance with an embodiment of the present disclosure. Figure 1 shows the relationship among each component but do not define the details such as position, shape, etc., of these components. The robotic arm 100 includes a frame unit 130, a motion unit 110, and a stiffness adjustment unit 120. The frame unit 130 is structured to support the motion unit 110 and the stiffness adjustment unit 120. The motion unit 110 can generally be configured in an elongated shape extending along its longitudinal direction.

The motion unit 110 includes elastic rods (not shown in Figure 1), the elastic rods are configured to move relative to the frame unit 130 along the longitudinal direction L. movement along the longitudinal direction L may include leftward movement and rightward movement, rather than in movement a single direction. For example, the elastic rods may be configured to be stretchable or contractable. When the elastic rods stretch or contract, the motion unit 110 is always supported by the frame unit 130 and other parts of the motion unit 110 may be fixed to the frame unit 130. The movement of the elastic rods may be driven by a driving member such as an actuator. Herein, moving along the longitudinal direction refers to an axial movement.

The stiffness adjustment unit 120 includes hollow stiffness adjustment tubes (not shown in Figure 1) which are configured to surround a section of the elastic rods. For example, the inner diameter of the stiffness adjustment tube may be slightly larger than the outer diameter of the elastic rod such that the stiffness adjustment tube can be sleeved surrounding elastic rod . The stiffness adjustment tube is movable along the longitudinal direction L. For example, the movement is a reciprocating movement, e.g. leftward movement and rightward movement, rather than a single direction movement. Such a movement of the stiffness adjustment unit relative to the elastic rods varies a length d of a first segment of the elastic rod not surrounded by the stiffness adjustment tubes at a first end (i.e., the left end as shown in Figure 1), wherein the first end of the elastic rods is an end far away from the frame unit. Variation of the length d of the first segment causes a change in the stiffness of the elastic rod at the first end. The stiffness adjustment tube can be driven by a driving component such as an actuator. Thereby, the stiffness of the operating end of the robotic arm 100 is adjustable as needs in real time.

Figure 2 is a perspective view of the motion unit 110 mounted to the frame unit 130 according to an embodiment of the present disclosure. Figure 3 is a perspective view of a frame unit 130 in accordance with an embodiment of the present disclosure. Figure 4 is a perspective view of components associated with the driving to elastic rods in the motion unit 110 which are mounted to the stoppers 131 of the frame unit 130, according to an embodiment of the present disclosure. Figure 5 is a perspective view of a lead screw connector 1 17 in accordance with an embodiment of the present disclosure. Hereinafter, examples of the motion unit 110 will be described with reference to Figure 2 to Figure 5.

According to an embodiment of the present disclosure, the frame unit 130 includes a base 132, stoppers 131, and a frame connector 133. In a specific example as shown in Figure 3, the frame unit 130 includes two stoppers 131, which are respectively fastened to one end of the base 132. Four frame connectors 133 are fastened between the stoppers 131 to make the entire frame unit 130 stronger. The base 132 of the frame unit 130 is used for connecting to an external structure, and the frame unit 130 is used for supporting the motion unit 110 and the stiffness adjustment unit 120. It should be understood that the number of the stoppers or the frame connectors is merely for illustration. According to an embodiment of the present disclosure, the motion unit 110 includes elastic rods 111 and connection tubes 112. Through holes are arranged in the stoppers 131. The connection tubes 112 are configured to pass through the stoppers 131 and be movable along the longitudinal direction L with respect to the stoppers 131. In a specific example as shown in Figure 2, the motion unit 110 has three elastic rods 11 1 and three connection tubes 112. Each elastic rod 111 is connected to a corresponding connection tube 1 12 at a second end adjacent to the frame unit 130. Each connection tube 112 passes through two stoppers 131 and is reciprocally movable along the longitudinal direction L relative to the two stoppers 131 (that is, the connection tubes 112 are not fixed to the stoppers 131 but freely pass through the through holes in the stoppers 131). The connection tubes 1 12 can be hollow or partially hollow such that the elastic rods 1 11 can be inserted into the connection tubes 1 12 and fastened thereto. Elastic rods 11 1 can be fastened to the connection tubes 1 12 in other ways. The connection tube 112 are substantially rigid while the elastic rods 11 1 are flexible but are capable of transmitting force in the longitudinal direction L (i.e., transmitting driving force along the axial direction). In other words, the connection tubes 112 are unbendable, and the elastic rods 1 11 are bendable under external force. In addition, in a specific example as shown in Figure 2, the elastic rods 11 1 are each arranged coaxial with a connection tube 112.

According to an embodiment of the present disclosure, the elastic rod 111 may have a universal joint 113 at its first end which is far away from the frame unit 130. In a specific example as shown in Figure 2, each of the three elastic rods 11 1 may have a universal joint 113 at its respective first end, and all the three universal joints 113 may be connected to a flange 1 14. Being a distal end of the robotic arm 100, the flange 114 may have a universal mounting mechanism 115 to which various tools may be attached. The universal joint 113 may be, for example, a universal joint for connecting the flange 114 to the elastic rod 11 so as to provide two degree of freedom of rotation. For example, the flange 1 14 may be a cylinder with threaded holes or the like, for enabling the rotational and translational movements of the robotic arm 100, wherein the threaded holes may be used for connecting a surgical instrument or tool. According to an embodiment of the present disclosure, lead screw connectors 117 are disposed between the two stoppers 131 and the connection tubes 112 are placed to pass through the lead screw connectors 117. The connection tubes 112 may be fastened to the lead screw connectors 117 such that movement or shifting of the lead screw connectors 117 along the longitudinal direction L can cause corresponding movement or shifting of the connection tubes 1 12 along the longitudinal direction L, which in turn causes the elastic rods 111 connected to the connection tubes 112 to move or shift along the longitudinal direction L,. The motion unit 110 may further include a lead screw 116 which also passes through and threadedly fits with the lead screw connectors 1 17. In a specific example as shown in Figure 4, the lead screw 116 may have a threaded section which is generally disposed between the two stoppers 131. For example, the lead screw 116 may be configured as constrained between the two stoppers 131 and freely rotatable. The lead screw 116 may extend out of the right stopper 131 such that the part of the lead screw 116 extending beyond the stopper 131 can be driven by an external driving member. In this example, the external driving member can drive the lead screw 116 to rotate, and thus cause the lead screw connectors 117 to move linearly along the longitudinal direction L via threaded coupling between the lead screw 116 and the lead screw connector 117, and which finally drive the elastic rods 1 11 to move linearly, as illustrated above.

According to an embodiment of the present disclosure, the motion unit 1 10 may have three parallelly disposed elastic rods 1 11. Each elastic rod 1 1 lean be independently controlled to move in the longitudinal direction L. Therefore, when the three elastic rods 11 1 are driven to move in a same direction, three universal joints 113 and the flange 1 14 may synchronously move along the longitudinal direction L as a whole. When only one or two of the elastic rods 11 1 are driven or the three elastic rods 11 1 are driven asynchronously, the flange 114 can rotate about two axes perpendicular to the longitudinal direction L. Thereby, movement of three degree of freedom at the distal end of the motion unit 110 can take place. In other words, the elastic rods 111, the universal joints 113 and the flange 1 14 form a flexible parallel platform having three degrees of freedom, the distal end of the platform is rotatable about two axes and translational movement along one axis. As a result of joint action of bending of the elastic rods 111 and rotation of the universal joints 113, the distal end of robotic arm 100 can be rotated with a smaller bending radius and high degree of flexibility.

According to an embodiment of the present disclosure, each connection tube 112 may be combined with one lead screw connector 117 and one lead screw 1 16, and be driven independently. Therefore, each of the three elastic rods 1 11 can be driven independently by driving corresponding one of the three lead screws 116. In a specific example as shown in Figure 5, each lead screw connector 117 may have one through hole 119 and one threaded hole 118. The connection tube 112 may be placed to pass through the through hole 119. The lead screw connector 117 can be further configured such that the connection tubes 112 can be fastened to the connector 117 via fasteners. The inner wall of the threaded hole 118 has threads fitting with the threads on the lead screw 116, such that the lead screw connector 117 can be driven by the rotation of the lead screw 116.

Figure 6 is a perspective view of the stiffness adjustment unit 120 mounted to a frame unit 130, in accordance with an embodiment of the present disclosure. Figure 7 is a perspective view of a lead screw connector 125 in accordance with an embodiment of the present disclosure. In the following description, Figures 6 and 7 are shown for better illustration of the examples of the stiffness adjustment unit 120 in accordance with the present disclosure.

According to an embodiment of the present disclosure, the stiffness adjustment unit 120 includes stiffness adjustment tubes 121 and connection rods 122. The stoppers 131 may have additional through holes formed thereon, and the connection rods 122 may be configured to pass through the stoppers 131 and movable in the longitudinal direction L with respect to the two stoppers 131. In one specific example as shown in Figure 6, the stiffness adjustment unit 120 has two connection rods 122 and three stiffness adjustment tubes 121. Each stiffness adjustment tube 121 and each connection rod 122 is fixed to an adjustment tube jointer 123, and each connection rod 122 may pass through two stoppers 131 and move back and forth along the longitudinal direction L with respect to the two stoppers 131 (i .e., the connection rod 122 may not be fixed to the stopper 131 but pass through the through holes of the stopper 131). Stiffness adjustment tube 121 is hollow and its inner diameter is larger or slightly larger than the outer diameter of the elastic rod 111, such that least a section of the elastic rod 1 11 may be surrounded by the stiffness adjustment tube 121. Alternatively, the stiffness adjustment tube 121 may be fastened to the connection rod 122 in other ways. Both the stiffness adjustment tubes 121 and connection rods 122 are generally rigid. The three stiffness adjustment tubes 121 may be positioned parallel to each other and function as a sleeve for the respective elastic rod 11 1 to independently move reciprocally in the longitudinal direction L. However, it will be appreciated that the form of three stiffness adjustment tubes 121 may not necessarily be adopted. The objective of the present disclosure can well be achieved as long as an alternative structure has openings corresponding to and can sleeve on the elastic rods 111 and to move back and forth along the longitudinal direction L.

According to an embodiment of the present disclosure, a lead screw connector 125 is disposed between two stoppers 131 and the connection rods 122 pass through the lead screw connector 125. The connection rods 122 may be fastened to the lead screw connector 125 such that movement or shifting of the lead screw connectors 125 along the longitudinal direction L can cause corresponding movement or shifting of the connection rods 122 along the longitudinal direction L, which in turn causes the adjustment tube jointer 123 and the stiffness adjustment tubes 121 to move or shift along the longitudinal direction L. Since a a length d of a first segment of the elastic rod 111 that is at the first end or in other words at a distal end away from the frame unit 130 is not surrounded by the stiffness adjustment tubes 121 is determined by the position of the stiffness adjustment tube 121 relative to the elastic rod 11 1, the movement of the stiffness adjustment tubes 121 surrounding the elastic rods 11 1 will vary the length d of the exposed first segment, and thus vary the stiffness of the first end of the elastic rods 1 11. The stiffness adjustment unit 120 may further include a stiffness adjustment unit lead screw 124, which may pass through and threadedly fit with the lead screw connector 125. In a specific example as shown in Figure 6, the stiffness adjustment unit lead screw 124 may have a threaded section which is generally disposed between the two stoppers 131. For example, the stiffness adjustment unit lead screw 124 may be constrained between and rotatable relative to the two stoppers 131. The stiffness adjustment unit lead screw 124 may extend out of the right stopper 131 such that the part of the lead screw 124 extending beyond the stopper 131 can be driven by an external driving member. In this example, the external driving member can drive the stiffness adjustment unit lead screw 124 to rotate, and thus drive the lead screw connector 125 to move linearly along the longitudinal direction L via threaded coupling with the lead screw 124, which will finally linearly drive the stiffness adjustment tubes 121, as illustrated above.

According to an embodiment of the present disclosure, each connection rod 122 may be combined with one lead screw connector 125 and one stiffness adjustment unit lead screw 124. Therefore, two connection rods 122 can be synchronously driven by rotating the stiffness adjustment unit lead screw 124. However, it should be understood that any number of connection rod 122, stiffness adjustment unit lead screw 124 and lead screw connector 125 can be used as long as the linear driving to the stiffness adjustment tube 121 can be achieved. In a specific example as shown in Figure 7, each lead screw connector 125 may have two through holes 127 and one threaded hole 126. The connection rods 122 pass through the through holes 127. The lead screw connector 125 can further be configured such that the connection rods 122 can be fastened to the lead screw connector 125 via fasteners. The inner wall of the threaded hole 126 has thread fitting with the stiffness adjustment unit lead screws 124, such that the lead screw connector 125 can be driven by the rotation of the stiffness adjustment unit lead screws 124.

Figure 8 is a perspective view of a stopper 131 in accordance with an embodiment of the present disclosure. With respect to the views in Figures 2-4 and 6, the stopper 131 in Figure 8 is shown in an upside-down orientation to show the contacting surface between the stopper 131 and the base 132. As shown in Figure 8, the stopper 131 may have three threaded holes 134 for receiving the respective lead screws 116 of the motion unit. A countersink may be formed in the threaded holes 134 so as to have the lead screws 116 constrained between the two stoppers 131, as shown in Figures 2 and 4. The stopper 131 may have a stiffness adjustment unit thread hole 135 for receiving the stiffness adjustment unit lead screw 124. A countersink may be formed in the threaded hole 135 so as to have the stiffness adjustment unit screws 124 constrained between the two stoppers 131, as shown in Figure 6. The stopper 131 may have three connection tube holes 136 through which the connection tubes 112 pass. As shown in Figure 6, the stopper 131 may have three connection tube holes 136 through which the connection rods 122 are passed. The stopper 131 may have four frame connection holes 138 for receiving the frame connector 133. For example, the frame connector 133 may be fastened to the stopper 131 with a fastener. The stopper 131 may have two bottom holes 139 for securing to the base 132 with fasteners, for instance. It will be appreciated that the number of the aforementioned holes is merely for illustration and any number of holes and corresponding number of mating members may be used.

Figure 9 is a perspective view of a robotic arm 100 in accordance with an embodiment of the present disclosure. As illustrated above, each elastic rod 111 can be individually actuated, achieving independent movement along the longitude direction L. Hence, the location of the flange 114 along the longitude direction L and the titling angle of the flange 1 14 can be precisely controlled. The movement of each elastic rod along the longitude direction L includes bidirectional movement, i.e., not only the movement away from the frame unit 130 but also the movement approaching the frame unit 130. On the other hand, the stiffness adjustment tubes 121 can be actuated together with the elastic rod 111 to achieve synchronous movement along the longitude direction L. Hence, the non-surrounded length d, at the first end of the elastic rod 1 11, which is far away from the frame unit 130, can be precisely controlled. In other words, the stiffness of the distal end of the robotic arm can be precisely controlled in real time as desired. Similarly, the movement of the stiffness adjustment tubes 121 along the longitude direction L maybe bidirectional, i.e., not only the movement away from the frame unit 130 but also the movement approaching the frame unit 130.

Figure 10 is a perspective view of a stand 200 in accordance with an embodiment of the present disclosure. The stand 200, for example, can support a plurality of robotic arms 100 as illustrated above. For example, the base 132 of the frame unit 130 can be secured to the stand 200 through slots 210. The position of the robotic arm 100 on the stand 200 may be adjustable via the slots 210 and the base 132 may be locked to the stand 200 via fasteners such as a bolt or the like (not shown). Since each robotic arm 100 may be provided with a respective slot 210, the distance between each robotic arm is adjustable. The stand may also have a camera head hole 220 for mounting an endoscopic camera head 300 on the stand 200.

Figure 11 is a perspective view of a robot 10 for minimal invasive surgery in accordance with an embodiment of the present disclosure. As shown in the figure, two robotic arms 100 and one endoscopic camera head 300 are mounted to the stand 200. The endoscopic camera head 300 is used for real time image navigation during surgical operation. The endoscopic camera head 300 is disposed close to the elastic rods 111 of the robotic arms 100 so as to achieve better view and better sharpness during surgical operation, such that the robotic arms is operable with higher degree of precision. In this example, two robotic arms 100 are used, allowing for six degree of freedom of operation.

Figure 12 is a schematic view of a robot 10 for minimal invasive surgery during operation on the laryngopharynx of a patient in accordance with an embodiment of the present disclosure. In an exemplary embodiment, the robot 10 for minimal invasive surgery operates as follows: the end of the flange 114 is fitted with surgical instruments; each lead screw 116 of the motion unit is connected to a driving device; and the endoscopic camera head 300 is connected to a terminal display device. One end of the robotic arm 100 having surgical instruments is brought to the laryngopharynx of the patient and the surgical instruments are moved to the focal zone by adjusting the location of the robotic arms 100 on the stand 200. By observing the lesion on the terminal display device and operating the driving device to change the end position and gesture of the robotic arms 100, a surgical operation is carried out. During the operation, the axial location of the stiffness adjustment tube 121 may be adjusted by rotating the stiffness adjustment unit lead screw 124 as needs, such that the stiffness of the distal end of the robotic arms 100 may be changed. After the surgery, the robotic arms 100 are removed out.

In accordance with an embodiment, the present disclosure provides a method 400 for manufacturing a robotic arm. As shown in Figure 13, the method includes: providing 401 a frame unit; providing 402 a motion unit supported by the frame unit, the motion unit including elastic rods configured to be operatively movable along the longitude direction of the elastic rods with respect to the frame unit; and providing 403 a stiffness adjustment unit supported by the frame unit, the stiffness adjustment unit including hollow stiffness adjustment tubes configured to surround a section of the elastic rods and are operatively movable along the longitude direction so as to vary the length of the elastic rods at a position non-surrounded by the stiffness adjustment tubes at a first end, and thus to adjust the stiffness of the first end of the elastic rods, wherein the first end of the elastic rods is an end far away from the frame unit.

In accordance with an embodiment, the present disclosure provides a method 500 for manufacturing a minimal invasive surgical robot. As shown in Figure 14, the method comprises: providing 501 a robotic arm as above-described; providing 502 a stand for supporting the robotic arm; and providing 503 an endoscopic camera head attached to the stand.

The robotic arm and robot for minimal invasive surgery according to multiple embodiments of the present disclosure have many benefits, such as: higher positioning precision and larger output force can be realized by using parallel mechanism based on elastic rods; smaller bending radius and more flexible as a result of the combined action of the bending of the elastic rods and the rotation of the universal joint; higher level of safety and wider application in that the stiffness of the distal end of the robotic arm is adjustable during operation; meeting the requirements for laryngopharyngeal surgery operation with two robotic arms having six degree of freedoms; and suitable for different surgical instruments in operation by using a universal structure at the distal end of the robotic arm, which is suitable for attaching thereto various types of surgical tools such as surgical forceps, surgical scissors, sintering tools, and so on. It should be appreciated that the exemplary embodiments are only examples, and are not intended to limit the scope of the disclosure in any way. A person skilled in the art would have the ability to understand that various changes may be made in the function and arrangement of elements and method of operation described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A robotic arm, comprising:

a frame unit (130);

a motion unit (110) including elastic rods, the motion unit (110) being supported by the frame unit (130), the elastic rods (111) being configured to be operably movable along a longitude direction ( L) of the elastic rods (111) with respect to the frame unit (130); and

a stiffness adjustment unit (120) including hollow stiffness adjustment tubes (121) supported by the frame unit (130), the stiffness adjustment tubes (121) being configured to surround a second segment of the elastic rods (111) and being operably movable along the longitude direction ( L) to vary a length (d) of a first segment of each of the elastic rods (111) to adjust a stiffness of a first end of each of the elastic rods, wherein the first segment is located at the first end of each of the elastic rods (111) away from the frame unit (130), and wherein the first segment is not surrounded by the stiffness adjustment tubes (121).

2. The robotic arm according to claim 1, wherein the frame unit (130) comprises two stoppers (131) and the motion unit (110) comprises connection tubes (112) configured to pass through the two stoppers (131) and be movable with respect to the two stoppers (131) along the longitude direction ( L) .

3. The robotic arm according to claim 2, wherein the elastic rods (111) are fixed to the connection tubes (1 12).

4. The robotic arm according to claim 3, wherein the motion unit (1 10) comprises a lead screw (116) and a lead screw connector (117) through which both the lead screw (116) and the connection tube (1 12) pass, wherein the connection tubes (1 12) are fastened to the lead screw connector (117), wherein rotation of the lead screws (1 16) of the motion unit drives the lead screw connector (117) to move along the longitudinal direction (L).

5. The robotic arm according to claim 4, wherein the lead screw (116) drive the lead screw connector (1 17) to move between the two stoppers (131) through threads formed on the lead screw (1 16) and the lead screw connector (1 17) .

6. The robotic arm according to any one of claims 2 to 5, wherein the motion unit (110) comprises three elastic rods (111), each elastic rod (11 1) extends into a corresponding connection tube (112) at a second end of the elastic rod (11 1), wherein the second end is adjacent to the frame unit (130).

7. The robotic arm according to claim 4 or claim 5, wherein the motion unit (110) comprises three elastic rods (111), each elastic rod (1 11) extends into a corresponding connection tube (112) at a second end of the elastic rod (11 1), wherein the second end is adjacent to the frame unit (130), wherein each connection tube (112) is fastened to a respective lead screw connector (117), wherein each lead screw connector (117) is capable of being driven by the lead screw (116) of a respective motion unit.

8. The robotic arm according to claim 7, wherein each elastic rod (1 11) has a corresponding universal joint (1 13) at the first end, each universal joint (1 13) is attached to a flange (114) for transmitting a movement of the elastic rod (111) along the longitudinal direction (L) to the flange.

9. The robotic arm according to claim 1, wherein the frame unit (130) includes two stoppers (131), and the stiffness adjustment unit (120) includes connection rods (122) each being adapted to pass through the two stoppers (131) and be movable with respect to the two stoppers (131) along the longitudinal direction (L)

10. The robotic arm according to claim 9, wherein the stiffness adjustment tubes (121) are fixed relative to the connection tubes (112).

11. The robotic arm according to claim 10, wherein the stiffness adjustment unit (120) comprises a stiffness adjustment unit lead screw (124) and a lead screw connector (125) through which both the stiffness adjustment unit lead screw (124) and the connection rods (122) pass, wherein the connection rods (122) are fastened to the lead screw connector (125), wherein rotation of the stiffness adjustment unit lead screw (124) drives the lead screw connector (125) to move along the longitudinal direction (L).

12. The robotic arm according to claim 11, wherein the stiffness adjustment unit lead screw (124) drives the lead screw connector (125) between the two stoppers (131) through threads formed on the lead screw (124) and the lead screw connector (125).

13. A minimal invasive surgery robot comprising:

a robotic arm (100) according to any one of claims 1 to 12;

a stand (200) for supporting the robotic arm (100); and

an endoscopic camera head (300) connected to the stand (200).

14. The robot according to claim 13, wherein the robot comprises two robotic arms

(100).

15. The robot according to claim 14, wherein the stand (200) comprises a slot (210) through which a base (132) of the frame unit (130) is fastened to the stand (200).

16. The robot according to any one of claims 13 to 15, wherein the minimal invasive surgery robot is a laryngopharyngeal surgery robot.

17. A method (400) for manufacturing a robotic arm, comprising:

providing (401) a frame unit (130);

providing (402) a motion unit (110) including elastic rods (111), the motion unit (110) being supported by the frame unit (130), the elastic rods (111) being adapted to be operably movable along a longitude direction ( L) of the elastic rods (111) with respect to the frame unit (130); and

providing (403) a stiffness adjustment unit (120) including hollow stiffness adjustment tubes (121), the stiffness adjustment tubes (121 ) being adapted to surround a section of the elastic rods (111) and being operatively movable along the longitude direction (L) so as to vary a length of a segment of each elastic rod (11 1) at a first end of the elastic rods (1 11) to adjust the stiffness of the first end of the elastic rods (1 11), wherein the segment of the elastic rod (1 11) is located away from the frame unit (130), and wherein the segment of the elastic rod (111) is not surrounded by the stiffness adjustment tubes (121).

18. A method (500) for manufacturing a minimal invasive surgical robot, the method comprising:

providing (501) a robotic arm (100) according to any one of claims 1 to 12; providing (502) a stand (200) for supporting the robotic arm (100); and providing (503) an endoscopic camera head (300) attached to the stand (200).