"Clamping mechanism"
Technical Field
[0001] The present disclosure relates to a clamping mechanism configured to hold an item. In some examples, the clamping mechanism is configured to selectively hold items. In some examples, the clamping mechanism is adapted for use with a robotic arm.
Background
[0002] Clamping mechanisms, such as clamps, can be used to hold items in place such as in a vice or at components of a robotic machine. In some examples, clamping mechanisms are configured to apply clamping force to items. This may include using C clamps to squeeze items together, such as when bonding two parts together.
[0003] Some clamping mechanism include threaded mechanism to enable selective actuation of clamp surfaces and to increase clamping force. However, this may result in overtightening where excessive forces are applied that can cause damage to the clamped item or the clamping mechanism.
[0004] In some examples, there is a relationship between clamping force displacement between the clamp surfaces. For example, a clamp may be configured to clamp with clamping surfaces that are designed to close at approximately X distance apart. This configuration enables the clamp to grip items that are also approximately X distance wide. However, if there are production variance in the size of the items, this may cause issues. For example, if the actual item is larger, say by 5%, this may result in the clamp applying excessive pressure to the item. Conversely, if the actual item is smaller, say by 5%, then the clamp may not apply sufficient force to hold the item at all.
[0005] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
[0006] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in thefield relevant to the present disclosure as it existed before the priority date of each claim of this application.
Summary
[0007] A clamping mechanism comprising: a first clamp member with a first clamp surface and a first actuation surface; and a second clamp member with a second clamp surface and a second actuation surface, wherein the second clamp surface is configured to oppose the first clamp surface and secure an item in between; and a selectively rotatable actuation component, wherein the actuation component includes a third actuation surface, wherein selective rotation of the actuation component in a first direction causes the third actuation surface to interact with the first and second actuation surfaces and, in turn, cause the clamping mechanism to transition from a released configuration to a clamped configuration where the first and second clamp surfaces apply clamping force(s) to the item, and wherein additional selective rotation of the actuation component in the first direction causes the third actuation surface to interact with the first and second actuation surface to cause the clamping mechanism to transition from the clamped configuration to the released configuration where the clamping force(s) to the item are reduced or removed.
[0008] In some examples of the clamping mechanism, the third actuation surface includes, at least in part, a cam surface.
[0009] In some examples of the clamping mechanism, the third actuation surface comprises, at least in part, an inwardly facing wall.
[0010] In further examples of the clamping mechanism, the inwardly facing wall has an substantially ellipse-shaped cross-section.
[0011] In some example of the clamping mechanism, the inwardly facing wall includes:
- a first pair of opposing wall portions of the inwardly facing wall separated by a first distance; and
- a second pair of opposing wall portions of the inwardly facing wall separated by a second distance, wherein the first distance is shorter than the second distance, and
wherein in the clamped configuration, the first pair of opposing wall portions are configured to draw the first and second actuation surfaces towards each other, and
wherein in the released configuration, the second pair of opposing wall portions are configured to enable the first and second actuation surfaces to, at least in part, separate away from each other.
[0012] In some examples, the clamping mechanism comprises a plurality of cam surfaces, wherein cam surfaces provide a transition between the first pair of opposing wall portions and the second pair of opposing wall portions.
[0013] In some examples, the clamping mechanism, further comprises one or more detents to aid retention of the actuation component in the clamped configuration and/or the released configuration.
[0014] In some examples of the clamping mechanism, the first actuation surface is at a first boss, and the second actuation surface is at a second boss.
[0015] In further examples of the clamping mechanism, the first and second boss are, at least in part, received between the inwardly facing wall.
[0016] In some examples of the clamping mechanism, the first clamp member is joined at a junction to the second clamp member.
[0017] In some examples of the clamping mechanism, the actuation component comprises a substantially circular body portion received in a corresponding socket formed at the first and second clamp members.
[0018] In some examples of the clamping mechanism, the actuation component further comprises a handle.
[0019] In some examples of the clamping mechanism, the third actuation surface of the actuation component comprises an outwardly facing wall, wherein the outwardly facing wall comprises:
- a first pair of opposite wall portions of the outwardly facing wall separated by a first distance; and
- a second pair of opposite wall portions of the outwardly facing wall separated by a second distance, wherein the first distance is shorter than the second distance, and
wherein in the clamped configuration, the first pair of of opposite wall portions are configured to enable the first and second actuation surfaces to draw towards one another, and
wherein in the released configuration, the second pair of opposite wall portions are configured to push the first and second actuation surfaces, at least in part, to separate away from each other.
[0020] In some examples the clamping mechanism is configured to be received at a robotic arm.
[0021] A clamping system comprising: a clamping mechanism described above; and a hollow first sleeve configured with an outward facing dimension, of an outward facing surface, and a hollow define by a first inward facing dimension of an interior surface. The first sleeve is configured to receive at least part of the item in the hollow of the sleeve; and wherein the first clamp member and the second clamp member are configured to clamp the outward facing dimension.
[0022] In some examples, the clamping system further comprises: a hollow second sleeve configured with the outward facing dimension of a corresponding outward facing sufrace and a second hollow to define a second inward facing dimension of a corresponding interior surface, wherein the second sleeve is configured to receive at least part of another item in the second hollow, and wherein the first clamp member and the second clamp member are configured to clamp the outward facing dimension, and wherein the outward facing dimension of the first sleeve is the same as the outward facing dimension of the second sleeve.
[0023] In some examples of the clamping system the hollow first sleeve has a first colour that is different to a second colour of the hollow second sleeve.
[0024] In some examples of the clamping system, the first sleeve is a tubular silicone sleeve.
[0025] A robotic arm comprising a clamping mechanism or a clamping system described above.
Brief Description of Drawings
[0026] Fig. 1 illustrates an example of a clamping system including a clamping mechanism;
[0027] Fig. 2 illustrates the clamping mechanism of Fig. 1 in a released configuration;
[0028] Fig. 3 illustrates the clamping mechanism of Fig. 1 in a clamped configuration;
[0029] Fig. 4 illustrates an isometric view of the first and second clamp members of the clamping mechanism of Fig. 1;
[0030] Fig. 5 is a top view of thefirst and second clamp members of Fig. 4;
[0031] Fig. 6 is an isometric view of a rotatable actuation component of the clamping mechanism of Fig. 1;
[0032] Fig. 7 is a bottom view of the rotatable actuation component of Fig. 6;
[0033] Fig. 8(a) is a top view of the clamping mechanism of Fig. 2 in a released configuration;
[0034] Fig. 8(b) is a partially sectioned top view of the clamping mechanism of Fig. 2 in a released configuration;
[0035] Fig. 8(c) is a partially sectioned isometric view of the clamping mechanism of Fig. 2 in a released configuration;
[0036] Fig. 9(a) is a partially sectioned top view of the clamping mechanism of Fig. 3 in a clamped configuration;
[0037] Fig. 9(b) is a top view of the clamping mechanism of the clamping mechanism of Fig. 3 in a clamped configuration;
[0038] Fig. 9(c) is a partially sectioned isometric view of the clamping mechanism of Fig. 3 in a clamped configuration;
[0039] Fig. 10(a) illustrates multiple sleeves, where the sleeves can be selectively used in the clamping system of Fig. 1;
[0040] Fig. 10(b) illustrates a cross-section of the clamping mechanism of Fig. 1 using a sleeve;
[0041] Fig. 11 is a bottom view of a rotatable actuation component in accordance with one variation;
[0042] Fig. 12(a) is a top view of a clamping mechanism in the clamped configuration in accordance with another variation;
[0043] Fig. 12(b) is a top view of a clamping mechanism in the released configuration in accordance with the variation of Fig. 12(a);
[0044] Fig 13 illustrates an example of a clamping mechanism with indexing markers used to calibrate and/or confirm positioning in a robotic arm system of a surgical robot; and
[0045] Figs. 14(a) and 14(b) are variations of the clamping mechanism with indexing makers.
Description of Embodiments
[0046] Overview
[0047] An example of a clamping mechanism 1 is illustrated in Fig. 1. This includes a first clamp member 3 with a first clamp surface 5 and a second clamp member 9 with a second clamp surface 11. The first clamp surface 5 opposes the second clamp surface 11 to secure an item 15 in between.
[0048] With reference to Fig. 4, the first clamp member 3 has a first actuation surface 7 and the second clamp member 9 has a second actuation surface 13. Referring to Figs. 1 and 6, the clamping mechanism 1 also includes a selectively rotatable actuation component 17, wherein the actuation component 17 includes a third actuation surface 19.
[0049] Selective rotation of the actuation component 17 in a first direction 21 causes the third actuation surface 19 to interact with the first and second surfaces 7, 13. This, in turn, causes the clamping mechanism to transition from a released configuration 23 (as illustrated in Figs. 2 and 8(a) to 8(c)) to a clamped configuration 25 (as illustrated in Figs. 3 and 9(a) to 9(c)) to apply clamping forces to the item 15.
[0050] Additional selective rotation of the actuation component 17 in the first direction 21 causes the third actuation surface 19 to interact with the first and second surfaces 7, 13 to cause the clamping mechanism to transition from the clamped configuration 25 to the released configuration 23 where the clamping force(s) to the item 15 are reduced or removed.
[0051] Figs. 6 and 7. illustrates an example of the third actuation surface 19 that includes an inwardly facing wall 29. The inwardly facing wall 9 has a first pair 33 of opposing wall portions 35, 37 separated by a first distance 39. The inwardly facing wall 9 also has a second pair 43 of opposing wall portions 45, 47 separate by a second distance 49. The first distance 39 is shorter than the second distance 49 so that when the first pair 33 of opposing wall portions interact with the first and second actuation surfaces 7, 13 this causes the clamp members 3, 9 to be drawn to the clamped configuration 25. On selective rotation of the actuation component 17, the first pair 33 disengage with the result of transitioning to the second pair 43 of opposing wall portions 45, 47 that, with a larger distance, enable the clamp members 3, 9 to separate to the released configuration 23.
[0052] As the first pair 33, and second pair 43 are disposed along an inwardly facing wall 29, rotation in the first direction 21 of the actuation component 17 will alternate between the clamped configuration 25 and the released configuration 23. In some examples, rotation in an opposite second direction 22 similarly alternates the clamping mechanism's configuration. Advantageously, the clamping mechanism can reduce or mitigate overtightening as continued rotation in a direction will only result in alternating in the clamped configuration 25 and released configuration 23. This is in contrast to other mechanisms, in particular mechanisms utilising a threaded mechanism where excessive rotation of the mechanism with increased torque can result in excessive clamping forces that can damage the item 15 and the clamping mechanism.
[0053] In this example the clamping mechanism 1 is located at a robotic arm 201 to hold an item 15 in the form of an end effector (as shown in Fig. 1). In particular, an ablation probe 15 is held between the first and second claim members 3, 9. Ablation probes 15, or other medical devices, may include a precise, yet delicate construction whereby excessive forces may damage the instrument, inaccuracy, or other undesired result.
[0054] In some examples, a hollow sleeve 103 is provided so that a part of the item 15 (such as the ablation probe) passes through a hollow 104 of the sleeve 103 and where the clamp members 3, 9 clamp against the outward surfaces of the sleeve 103. Various sizes of hollow sleeves 103, 111 may be provided to match the corresponding sizes of items 15, 115 so that appropriate clamping forces are applied to the item. This can reduce the risk of too much force (that would damage the item 15) or too little force (that would allow the item 15 to slip out of the clamp).
[0055] Components of a specific, and non-limiting, example of the clamping mechanism will now be described in detail.
[0056] Arms of the clamp
[0057] Figs. 4 and 5 illustrate the first clamp member 3 and second clamp member 9 that are inthe form of arms. The arms of the clamp members 3, 9 are joined at a junction 53.
[0058] In this non-limiting example, the first and second clamp members 3 are formed in a continuous integrally formed piece, such as forging as a single piece, machining a billet to form the clamp members, and or welding the clamp members 3, 9 together at the junction 53. When relatively small external forces are applied, the arms of the clamp member 3, 9 may elastically deform. For example, if the clamp members 3, 9 are forced together by an external force, the clamp members 3, 9 may resiliently spring back apart once the external force is removed. Similarly, if the clamp members 3, 9 are forced apart by an external force, the clamp members 3, 9 may spring back together to the original state. This resilient construction can assist, at least in part, the transition between the released configuration 23 and clamped configuration 25.
[0059] It is to be appreciated that in alternative examples, the arms of the first clamp member 3 and second clamp member 9 are separately formed and are fastened together at, or near a junction 53.
[0060] A socket 63 is formed, at least in part, at the arms of the first and second clamp members 3, 9. This socket 63 is configured to receive, at least in part, a body portion 61 of the actuation component 17. The socket 63 supports the actuation component 17 and is configured to enable the actuation component 17 to be selectively rotated in the socket 63 in the first direction 21.
[0061] Between the clamp surfaces 5, 11 and the junction 53 are the respective first and second actuation surfaces 7, 13. The actuation surfaces 7, 13 enable forces applied thereto to cause transmission of motion and/or forces to the first and second clamp surfaces 5, 11 located proximal to ends of the clamp members 3, 9. The first actuation surface 7 is located at a first boss 57 and the second actuation surface 13 is located at a second boss 59. In this example the first and second boss 57, 59 are located in the socket 63. In particular, the first and second boss 57,59 are configured to protrude towards the actuation component 17 to enable the first and second actuation surfaces 7, 13 to interact with the third actuation surface 19 of the actuation component 17 described below.
[0062] At the clamp surfaces 5, 11 as illustrated in Fig. 5, these can include concave surfaces to assist positioning of the item 15 held in between. In some examples where a hollow sleeve 103, 111 is used, the concave surfaces may have a curvature to match the outward facing dimension 105 of the hollow sleeve. In other alternatives, the clamp surfaces 5, 11 may be profiled to match the item 15 expected to be clamped. In yet other alternatives, the clamp surfaces 5, 11 may include teeth or other surface contours to assist positioning, gripping, etc.
[0063] The first and second clamp member 3, 9 may be made of materials such as polymers, fibre reinforced plastics (e.g. carbon fibre and/or glass reinforced plastics).
[0064] In some examples, it is desirable to use radio translucent materials for the clamp member 3,9 and other components of the clamping mechanism 1. Such radio translucent materials (in contrast to metal and metal alloys) have the advantage of reduced interference with X ray, computerised tomography (CT), and other imaging techniques.
[0065] Referring to Figs. I to 5, the arms of the clamp members 3, 9 and the junction 53 have an L-shaped profile when viewed from the side. In particular, the clamp members 3, 9 extend from the junction 53 with an offset 70 from a rotation axis 72 of the clamping mechanism 1 as illustrated in Fig. 3. The rotation axis 72 is the rotational axis in which the clamp mechanism 1 is coupled to another part of a machine, such as robotic arm with rotatable actuators. This can include a rotatable coupling to manipulate the position and/or orientation of a surgical tool held in the clamp.
[0066] In this example, the arms of the clamp members 3, 9 are offset (an in this case biased towards the bottom/lower region. This can be advantageous in enabling maximum use of the surgical tool (such as an end effector/ablation probe) held in the clamp. In particular, holding the surgical tool at a lower region enables the surgical tool to be held closer to a patient positioned underneath the mechanism 1. This can enable the probe maximum utility allowing the probe to selectively extend, or reach, as deep as possible into the patient. This is in contrast to systems where the arms of the clamp are close to, or at, the rotation axis 72.
[0067] This configuration can have particular advantage in situations where a robotic arm (with the clamp mechanism 1) is operating in and around a SPECT/CT imaging system where there is limited space.
[0068] It is to be appreciated that the above has been described with reference to the offset being relatively lower to the rotation axis 72 where a patient is below the mechanism 1. It is to be appreciated that other configurations can be used and adapted for similar advantages. For example, if it is desirable for the probe to approach a patient from the side, the respective offset 70 may be provides sideways (instead of downwards).
[0069] Rotatable actuation component /cap
[0070] The rotatable actuation component 17 functions as the user operable component to selectively change the clamping mechanism 1 between the clamped configuration 25 and the released configuration 23. This can be achieved by operating a handle 65 of the rotatable actuation component 17 that can also function as a tactile and visual indicator of the configuration state of the clamping mechanism 1 as illustrated in Figs. 2 and 3.
[0071] The rotatable actuation component 17 may include a cap-like circular body portion 61 that is received in the corresponding socket 63.
[0072] The inside, and important structural features, of the actuation component 17 is best illustrated in Figs. 6 and 7. The third actuation surface 19, in this example, includes an inwardly facing wall 29 to interact with the first and second actuation surfaces 7, 13, such as those on the boss 57, 59 described above.
[0073] In some examples, the third actuation surface 19 includes, at least in part, one or more cam surfaces 27, 51 to assist in transition between the released configuration 23 to the clamped configuration 25. In particular, the cam surface(s) 27 aid in converting torque applied to the handle 65 to clamp force(s) from the third actuation surface 19 interacting with the first and second surfaces 7, 13.
[0074] In the example illustrated in Fig. 7, the inwardly facing wall 29 has a substantially ellipse-shaped 31 cross-section. Thus the curvature of the ellipse provides, at least in part, the cam surface(s) 27. Although the example of Figs. 6 and 7 illustrate an ellipse-shaped 31 cross section, it is to be appreciated that the third actuation surface 19 may include multiple facets, subsurface, and/or curvatures.
[0075] Fig. 7 illustrates the first pair 33 of opposing wall portions 35, 37 of the inwardly facing wall 29 separated by a first distance 39. The second pair 43 of opposing wall portions 45, 47 are separated by a second distance 49. The first distance 39 is shorter than the second distance 49 such that in the clamped configuration 25, the first pair 33 of opposing side portions 35, 37 are configured to draw the first and second actuation surface 7, 13 (including the respective bosses 57, 59) together. This results in drawing the arms of the first clamp member 3 and second clamp member 9 together (as illustrated in Figs. 9(a) to 9(c)).
[0076] When the actuation component 17 is rotated to the released configuration 23, the second pair 43 of opposing wall portions 45, 47 with the larger second distance 49 enable the first and second bosses 57, 59 to separate a greater distance. Thus this allows a reduction or release of the clamp forces. In some examples, the resilience of the first and second clamp members 3, 9 spring the first and clamp surfaces 5, 11 outwards to release the item 15.
[0077] In this example, the transition between the first pair 33 of opposing wall portions and second pair 43 of opposing wall portions are provided by cam surfaces 27, 51 of the ellipse shaped cross-section. However, it is to be appreciated that alternative shapes and profiles for a plurality of cam surfaces 51 can be provided to transition between the wall portions 35, 37, 45, 47. This may include a substantially flat cam surface, serpentine, etc. In some examples, the surfaces may include notches to enable a user to progressively select a desired clamping force. This may enable tactile, and/or audible feedback on progressive application of the clamp towards the clamped configuration 25.
[0078] In some examples, one or more detents 55 are provided to aid retention of the actuation component 17 in the clamped configuration 25 and/or the release configuration 23. These can include a scallop, curvature, or groove of a relatively small radius at one or more of the opposing wall portions 35, 37, 45, 47. This can enable thefirst and second actuation surfaces 7, 13 and the respective bosses 57, 59 to settle into the detent 55 to prevent unwanted rotation of the actuation component 17. The detent 55 may be overcome by additional force applied by the user on the handle 65 to selectively rotate the actuation component 17 when desired.
[0079] The actuation component 17 may be made of materials such as polymers, fibre reinforced plastics (e.g. carbon fibre and/or glass reinforced plastics). In some examples, it is desirable select radio translucent materials for the actuation component 17 for the advantages noted above.
[0080] Mode of operation/method
[0081] Figs. 8(a) to 8(c) corresponding to the released configuration 23 and Figs. 9(a) to 9(c) corresponding to the clamped configuration 25 best illustrate the operation of the clamping mechanism 1.
[0082] Referring to Fig. 8(b) the superimposed ellipse 31 representing the inwardly facing wall 9 is configured so that the wider second distance 49 of the ellipse enables the boss 57, 59 to separate relative to each other for the released configuration 23. When the handle 65 is rotated, in this case by 90 degrees, the ellipse is configured as illustrated in Fig. 9(a). In this configuration, the inwardly facing wall 9 is configured so that the shorter first distance 39 pulls the boss 57, 59 to each other that results in the first clamp member 3 and second clamp member 9 being drawn to each other to provide clamping force(s) at the clamp surfaces 5, 11 (for the clamped configuration 25).
[0083] It is to be appreciated that further rotation, such as by 90 degrees, will bring the clamping mechanism 1 back to the released configuration 23 as shown in Figs. 8(a) to 8(c).
[0084] In this example, it is to be appreciated that the actuation component 17 can be rotated in either direction. This can include a clockwise in a first direction 21 as shown in Fig. 1 or in an anti-clockwise second direction. This bi-directional operation allows flexibility for the operator to rotate the handle 65.
[0085] Furthermore, as illustrated in Fig. 8(a) and Fig. 9(b), it is easy for an operator to identify the configuration of clamping mechanism 1 from the direction the handle 65 is facing. In Fig. 8(a) the handle in a perpendicular direction crossing both clamp members 3, 9 would always (in this example) correspond to the released configuration 23. That is, if the handle was rotated a further 180 degrees, this will result in the clamping mechanism 1 in the released configuration. Similarly, in Fig. 9(b) the handle in a direction parallel to the arms of the clamp members 3, 9 will always (in this example) correspond to the clamped configuration 25.
[0086] System with sleeves
[0087] There is also disclosed a clamping system 101 (as illustrated in Fig. 1) that includes the clamping mechanism 1 and the hollow first sleeve 103. The clamping system 101 may include multiple hollow sleeves 103, 111 with different dimensions of the hollow 104 that are sized to match and receive the item 15, 115.
[0088] In one example, the system of multiple hollow sleeves (such as first and second hollow sleeves 103, 111) that have similar outward facing dimensions 105, of an outward facing surface, configured to be received between the clamp surfaces 5, 11. However, the inward facing dimensions 107, 117, of an interior surface in the hollow, may be different to accommodate the size of different items 15, 115. An advantage of this system of matching hollow sleeves 103, 111 is to enable to selection of clamping forces to be applied to the item 15, 115. In some examples, this may include a system to apply substantially the same clamping force for different items 15, 115 and, through selecting an appropriate hollow sleeve 103,111, allow use of the same clamping mechanism 1.
[0089] Figs. 10(a) illustrate multiple sleeves with different inward facing dimensions 107, 117 that, in this case, are different internal diameters. The hollow sleeves 103, 111 in this example are substantially cylindrical and thus the outward facing dimensions 105 is of substantially constant diameter.
[0090] Fig. 10(b) illustrates a cross-section of the clamping mechanism 1 where the first hollow sleeve 103 is held between the first and second clamp surfaces 5, 11. The hollow 104 enables an item 15, such as an ablation probe to be inserted through the sleeve 103. In some examples, the sleeve may include a slit 114 (see Fig. 10(a)) or opening leading to the hollow 104 to enable the sleeve 103 to be laterally slipped onto an elongated item 15. This may be advantageous for items where the end is enlarged, or bulbous, such that the item 15 cannot be easily inserted through the hollow 104. The sleeve 103 may also include a collar 112 to aid location and retention of the sleeve to the clamping mechanism 1. The collar 112 may also serve to guide the item 15 when locating the item in the clamping mechanism 1.
[0091] In some examples, the hollow sleeve 103, 111 is a substantially tubular silicone sleeve. The silicone sleeve is a resilient, and slightly elastically deformable, material that can absorb some clamping forces. This may assist in distribution of forces across surfaces of the item 15 clamped by the clamping mechanism 1 which can reduce the likelihood of damage from excessive clamping forces. The material may also assist in clamping of items 15 that have some small variance in sizes.
[0092] In some examples, the hollow sleeves are colour coded to differentiate between dimensions of the sleeves. In some examples, the colour represents the different inward facing dimension of the sleeve. This may include the internal diameter of the hollow 104. In further examples, the colour is associated with the type and size of item 15, 115 to be clamped. For example, a particular ablation probe size may be associated with a particular colour of hollow sleeve. This enables the operator to quickly and easily identify appropriate sleeves 103, 111 to be used. In some examples, the item 15, 115 (or a portion of the item) may also be colour coded (or have reference to a colour) so an operator can match the colour of the item 15, 115 with the sleeve 103, 111.
[0093] Robotic arm
[0094] The clamping mechanism 1 may have particular application for robotics used in the medical industry. In some examples, the clamping mechanism 1 or system 101 is used with a robotic arm 201 of a surgical robot used for surgery. This can include holding an end effector, such as an ablation probe.
[0095] In some examples, the clamping mechanism 1 is coupled to a rotary actuator at an end of the robotic arm 201. The robotic arm 201 may include additional joints and degrees of freedom to manipulate the item 15.
[0096] The clamping system 1 enables easy insertion and securing of items 15, such as delicate surgical tools and instruments. This can reduce the instances of incorrectly secured items 15, that can cause damage to the equipment, sub-optimal or inefficient use of equipment, erroneous readings from sensors, or worse cause injury and harm to the user and patient.
[0097] Advantages
[0098] One advantage of examples of the clamping mechanism 1 is to prevent, or reduce the likelihood of overtightening the clamping mechanism 1 and causing damage to the item 15 or the clamping mechanism 1. After the clamping mechanism is a the clamped configuration 25, any further operation of the rotatable actuation component 17 will release the clamping mechanism 1 instead of applying increased, and potentially damaging, forces. This can be in contrast with other fastening systems, such as torquing a threaded mechanism that may result in excessive clamping forces.
[0099] In some examples, the clamping mechanism 1 may be made entirely, or substantially, out of radio translucent materials. This is in contrast with other clamping mechanisms with metal and metal alloy components such as springs, clamping members, etc. A technical advantage of the clamping mechanism using radio translucent materials that can operate to clamp without metal components is to prevent interference with imaging techniques such as CT, X ray, cone beam computed tomography (CBCT), etc.
[0100] In example of the system 101 using the sleeve 103, 111 the sleeves can assist proper placement and clamping of items 15, 115. This can also ensure proper clamping forces are applied with consideration of the respective sizes of the items 15, 115.
[0101] Other advantages of features of the present disclosure have been discussed throughout this specification.
[0102] Variation - Actuation component with multiple wall portions
[0103] Fig. 11 illustrates a variation of the actuation component 17. In this example, the inwardly facing wall 29' is profiled so that there are two pairs of opposing wall portions 35, 37 with two shorter distance 39. There are also two pairs of opposing wall portions 45, 47 with two relatively longer distances 49.
[0104] Thus in this example, a rotation 50 of the actuation component by 45 degrees is sufficient to transition the clamping mechanism 1 from the clamped configuration 25 to the released configuration 23.
[0105] It is to be appreciated that in alternative configurations, the internally facing wall 29 can have alternative shapes and profiles. This can include profiles that have number of opposing wall portions with progressively shorter (or longer) distances so the user can incrementally increase clamping pressure.
[0106] Variation - Actuation component spreads the clamp members
[0107] Figs. 12(a) and 12(b) illustrate a variation of the clamping mechanism 1' where the selectively rotatable actuation component 17' operates to spread the clamp members 3, 9 or to enable the clamp members 3, 9 to clamp towards each other to clamp.
[0108] Referring to Fig. 12(a), the clamp members 3, 9 are at, or have moved towards, their rest state. The rotatable actuation component 17 is positioned between the first and second actuation surfaces 7, 13. The third actuation surface 19 of the actuation component 17' includes an outwardly facing wall 71 to enable the actuation component 17 to selective spread the clamp members 3, 9 apart. In this example, the outwardly facing wall 71 includes a ellipse-shaped cross section. The outwardly facing wall 71 includes a first pair 73 of opposite wall portions 75, 77 separated by a first distance 79. The first distance 79 is a relatively shorter distance so that the clamp members 3, 9, that may be biased towards each other can provide clamping force(s) to items between the clamp surfaces 5, 11.
[0109] The rotatable actuation component 17' does not directly apply a clamping force on the clamp members 3, 9, but instead enables the clamp members 3, 9 to be biased toward each other. That bias may be from resilient deformation of the clamp members 3, 9 or from another biasing means. Such alternative biasing means may include a spring, pneumatic system, etc, where forces can be controlled.
[0110] Advantageously, the clamping forces (including maximum clamping forces) maybe specified by design of the clamp members 3, 9 and actuation component 17 to provide a limit (or range) of clamping forces that could be imparted on the item 15.
[0111] Turning to Fig. 12(b) the rotatable actuation component 17' has been rotated so that a second pair 83 of opposite wall portions 85, 87 of the outwardly facing wall push the first and second actuation surfaces 7, 13 to separate by approximately the second distance 89. Thus
Fig. 12(b) illustrates a released configuration 23'. Further rotation of the actuation component 17' enables the clamping mechanism I to be configured to the clamped configuration 25' as shown in Fig. 12(a).
[0112] Variation - Markers
[0113] Figs. 13 and 14 illustrate an example of the clamping mechanism 1 with markers 80, 80', 80" to assist calibration and indexing. This can include calibration and indexing of the clamping mechanism 1, relative to a robotic arm, and/or a surgical robot.
[0114] Referring to Fig. 13, the clamping mechanism has respective line markers 80, 80', 80" on the clamp members 3, 9 and actuation component 17. In this example, this includes a line. The line may be provide in contrast to the remaining components of the clamping mechanism. In some examples, the line may be a painted line. In other examples, other application of colour may be used to provide the contrast. This can include printed lines, stickers, etc. In some examples, the markers 80 may be etched onto the surface of the components. In yet other examples, the markers may be formed on the components, such as by machining, moulding, laser etching, etc. In yet other examples, the markers may be a provide with combination of techniques disclosed herein, such as etching followed by application of paint in the etched surface.
[0115] In the illustrated example, line markers 80, 80', 80" can be desirable as they can be used in conjunction with other hardware that can aid in indexing and calibration. In particular laser light sources 84, 84', 84". The laser light sources may selectively project light 86, 86', 86" towards the mechanism, which in this example forms respective indexing lines 88, 88', 88". These laser light sources 84 may include those existing in a SPECT/CT machine . In other examples, these laser light sources may be specified for inclusion in the surgical robot system as an indexing and calibration tool.
[0116] Having markers 80 and laser light sources on multiple, and different, planes enables calibration on multiple axes and degrees of freedom. In this example, this includes markers 80 on a top surface of the clamp members 3, 9 and at a side surface of the clamp member 9 (that is perpendicular to the top surface). It is to be appreciated that additional markers could be provided on the opposite side surface of clamp member 3 and the bottom surface of the clamp members. This example also includes a line marker 80" on the actuation component 17 and in addition to positioning for indexing and calibration purposes the line marker can be used to confirm the configuration (i.e. released or clamped configurations 23, 25). This is illustrated in Fig. 14(a) where the actuation component 17 is at a released configuration 23, and where marker 80" is perpendicular in configuration compared to the clamped configuration in Fig. 13.
[0117] In some examples, the markers may include a colour that is different to the laser light for ease of identification of alignment/mis-alignment. For examples, the laser light sources 84 may project a red colour and the markers may be selected specifically with a non-red colour, such as green. Thus when the laser light is projected onto the marker 80, there will be minimum reflection from the marker 80. However, if there is a mis-alignment to another part of the clamping mechanism 1, then the red laser light will be more clearly reflected.
[0118] It is to be appreciated other variations, including an inverse configuration could be used. For example, the marker 80 may have a colour that matches the light source and the remaining surfaces of the clamping mechanism is coloured to reduce reflection of the laser light. Thus when the light coincides with the marker 80, there will be an easily recognisable reflection whereas when the laser light hits the other surfaces there will be less (or muted) reflection.
[0119] With these different variations, one advantageous configuration is to enable a visible colour transition between an aligned state (i.e. where the laser light indexing lines 88 is on the marker 80) versus a non-aligned state (i.e. where the laser light indexing line 88 is not impinging on the marker 80).
[0120] In other example, the marker may be other visual markers that are non-linear. This can include circles, dots, or patterns. Fig. 14(b) illustrates another variation where the markers 80, 80', 80"' include plurality of a cross (+) patterns. The cross pattern may, in some cases, provide additional accuracy by enabling confirmation of alignment in additional axes. This may be achieved by the laser light source 84 projecting a corresponding cross pattern. In other examples, the laser light source may sequentially project lines 88 at different times (and in perpendicular projections) to coincide with each line of the cross. The example of Fig. 14(b) also includes an additional marker 80'" at the clamp member 9 that can provide an additional data point for checking to increase accuracy and to provide redundancy. This additional redundancy may be useful if the surgical tool held by the clamp interferes with using the other markers 80, 80'.
[0121] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.