Robot joints including remote motion centers

Abstract

An embodiment includes an exoskeleton robotic system including a parallelogram-based remote center of motion (RCM) joint. The RCM mechanism includes a first link coupled to a second link, a third link, and a fourth link. A motor is coupled to the third link. A first link of the first, second, third, or fourth links includes a first flexure. The first flexure includes a first degree of freedom in a first direction. A second link of the first, second, third, or fourth links includes a second flexure, and the second flexure includes a second degree of freedom in a second direction. The first direction is not parallel to the second direction.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to the field of robotics, and in particular to remote center of motion (RCM) mechanisms.

[0002] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. Provisional Patent Application No. 63 / 419,377, entitled "Robotic Joint Including a Remote Center of Motion Mechanism," filed October 26, 2022, the contents of which are incorporated herein by reference. [Background technology]

[0003] As described in U.S. Patent No. 10,463,560, an exoskeleton is a mechatronic system worn by a person to provide direct mechanical power transmission from the exoskeleton. These robotic mechanisms have been used in a variety of applications, including teleoperation, human function augmentation, rehabilitation, and assisting disabled people with motor control. However, many of these applications for exoskeletal devices have yet to achieve widespread adoption or practical implementation.

[0004] One example of an area where these devices are proposed is in the treatment of stroke. Strokes affect thousands of Americans each year, and the recovery process is long, difficult, and expensive. The use of robotic exoskeletons has the potential to reduce the length, difficulty, and cost of this recovery process. Various approaches have been proposed to provide robotic exoskeletons for the upper body.

[0005] Such exoskeletons often use a parallelogram-based remote center of motion (RCM) mechanism, which generates the desired rotation around a central point where no physical joints exist. [Brief explanation of the drawings]

[0006] Features and advantages of embodiments of the present invention will become apparent from the appended claims, the following detailed description of one or more embodiments, and the corresponding drawings. Where considered appropriate, reference labels have been repeated among the figures to indicate corresponding or analogous elements. [Figure 1A] FIG. 1 is a perspective view of one embodiment. [Figure 1B] FIG. 1 illustrates a top view of one embodiment. [Figure 1C] FIG. 1 illustrates a top view of one embodiment. [Figure 1D] FIG. 1 illustrates a top view of one embodiment. [Figure 2A] FIG. 1 is a perspective view of one embodiment. [Figure 2B] FIG. 1 is a perspective view of one embodiment. [Figure 3A] FIG. 1 illustrates a top view of one embodiment. [Figure 3B] FIG. 1 is a perspective view of one embodiment. [Figure 4A] FIG. 1 illustrates a top view of one embodiment. [Figure 4B] FIG. 1 is a perspective view of one embodiment. [Figure 5A] FIG. 1 illustrates a top view of one embodiment. [Figure 5B] FIG. 1 illustrates a top view of one embodiment. [Figure 5C] FIG. 1 illustrates a top view of one embodiment. [Figure 5D] FIG. 1 illustrates a top view of one embodiment. [Figure 6A] FIG. 1 is a perspective view of one embodiment. [Figure 6B] FIG. 1 is a side view of one embodiment. [Figure 7A] FIG. 1 illustrates a top view of one embodiment. [Figure 7B] FIG. 1 illustrates a top view of one embodiment. [Figure 8A] This is a model of a parallelogram RCM. [Figure 8B] This is a model of a parallelogram RCM. [Figure 8C] This is a model of a parallelogram RCM. [Figure 8D] This is a model of a parallelogram RCM. [Figure 9A] FIG. 1 is a perspective view of one embodiment. [Figure 9B] FIG. 1 is a bottom view of one embodiment. [Figure 9C] FIG. 1 illustrates a top view of one embodiment. [Figure 9D] FIG. 1 is a perspective view of one embodiment. [Figure 9E] FIG. 1 is a perspective view of one embodiment. [Figure 9F] FIG. 1 is a perspective view of one embodiment. [Figure 9G] FIG. 1 is a side view of one embodiment. [Figure 10A] FIG. 2 is a bottom view of the RCM mechanism. [Figure 10B] FIG. 2 is a bottom view of the RCM mechanism. [Figure 10C] FIG. 2 is a bottom view of the RCM mechanism. [Figure 11A] FIG. 10 illustrates a structure that does not conform to the transfer equation. [Figure 11B] FIG. 1 shows a structure that conforms to the transfer equation. DETAILED DESCRIPTION OF THE INVENTION

[0007] Reference is now made to the drawings. In the drawings, like structures may be labeled with like reference numeral suffixes. To more clearly illustrate the structures of various embodiments, the drawings included herein are schematic representations of the structures. Thus, the actual appearance of a fabricated structure, for example in a photograph, may look different (e.g., walls may not be exactly perpendicular to one another in an actual fabricated device) while still including the structures claimed in the illustrated embodiment. Furthermore, the drawings may show only structures useful for understanding the illustrated embodiment. To maintain clarity of the drawings, additional structures known in the art may not be included. For example, not all layers of a device are necessarily shown. "One embodiment," "various embodiments," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but not all embodiments necessarily include the particular feature, structure, or characteristic. Some embodiments may include some, all, or none of the features described for other embodiments. "First," "second," "third," etc. describe a common object and indicate that different instances of the same object are referenced. These adjectives do not imply that the described objects must be arranged in a particular order in time, space, sequence, or otherwise. "Connected" indicates that elements are in direct physical contact with each other, and "coupled" indicates that elements cooperate or interact with each other, but may or may not be in direct physical contact. A phrase such as "comprising at least one of A or B" includes situations of A, B, or A and B.

[0008] Applicant has determined that current manual techniques for physical therapy for the rehabilitation of neurological and neuromuscular disorders have many shortcomings. Robotic therapeutic devices could provide beneficial improvements, but are limited by system requirements that require highly precise and expensive manufacturing techniques to ensure proper system operation. The embodiments described herein address these problems.

[0009] The following is a list of definitions: A "remote center of motion" (RCM) is an axis of rotation away from a bearing or mechanical support. A "degree of freedom" (DOF) is the number of independent parameters (measurements) required to uniquely define the position of a system in space at any instant. A "binary link" is a linkage consisting of two joints, and a "ternary link" is a linkage consisting of three joints. The "mobility equation for a planar mechanism" is M = 3L - 2J - 3G (M = predicted degrees of freedom, L = number of links including the ground link, J = number of joints, G = number of ground links). An "over-constrained mechanism" is a mechanism with more degrees of freedom than predicted by the mobility equation. This over-constraint occurs due to the presence of redundant joints in the mechanism. See, for example, Figure 11B (DOF = 0 is consistent with the mobility equation) and Figure 11A (DOF = 1 is inconsistent with the mobility equation due to the unique geometry of the device). A "redundant joint" is a joint that constrains the same degree of freedom as other joints in the same mechanism. A "revolute joint" is a joint with one degree of freedom that constrains two links to rotation about an axis. A "prismatic joint" is a joint with one degree of freedom that constrains two links to translation along an axis. An "inflection point" occurs when each member of a parallelogram is aligned, allowing a parallelogram mechanism to change shape from a parallelogram to an antiparallelogram. A "flexure" is an elastic member configured to flexibly absorb stress and / or strain due to misalignment or misorientation.

[0010] The equations of motion for a planar mechanism are sufficient to determine whether a planar system is an "over-constrained mechanism." For example, Figure 8A shows a model of a planar parallelogram-based RCM mechanism. The RCM mechanism includes joints (A, B, C, D, E, F, G, H), two-way links (GH, CF), three-way links (AC, DF, AG, BH), and an RCM (J). Link GH is the ground link. The RCM mechanism includes redundant joints A, B, D, and E that result from the parallelogram configuration of the mechanism.

[0011] The RCM mechanism in Figure 8A is over-constrained due to the redundant joint; even though the planar translation equation predicts -1, the RCM mechanism only has one degree of freedom about RCM J. Figures 8C and 8D show a similar planar parallelogram-based RCM mechanism without joint A. Removing one joint has the effect of increasing the predicted degrees of freedom from the planar translation equation by two. Therefore, the predicted degree of freedom of the system is one and therefore not over-constrained. This type of single mechanism can operate in both parallel (Figure 8C) and anti-parallel (Figure 8D) configurations. When links BH and CF become collinear, the mechanism operates at a change point, allowing the system to freely switch between the parallel and anti-parallel configurations. This unpredictable behavior is undesirable in the embodied design because, in the anti-parallel configuration, link CF no longer rotates about J. The presence of redundant joint A enforces the parallelism of links AC and DF, preventing the mechanism from reaching the anti-parallel configuration at the change point. Figure 8B shows a parallelogram-based RCM mechanism with the addition of prismatic joints F1 and F2. Links ABC become pseudo-links A-F1 and F1-B1-C, while links ADG become pseudo-links A-F2 and F2-D1-C. Joints F1 and F2 are called pseudo-links because they only allow small displacements. Because this mechanism has two more pseudo-links and joints than the mechanism shown in Figure 8A, there are two extra predicted degrees of freedom even without the anti-parallel geometry associated with Figure 8D. For example, in Figure 8B, link ABC is still called a "ternary link" even though it is an A-F1 binary link and an F1-BC ternary link.

[0012] 1A, 1B, and 1C illustrate a physical embodiment of a parallelogram-based RCM mechanism coupled to a bracket 17. The mechanism includes links 1, 2, 3, and 4 and a remote rotation axis 18. The RCM mechanism is similar to the mechanism shown in FIG. 8A and includes joints (A, B, C, D, E, F, G, and H), two-way links (GH and CF), three-way links (ABC, DEF, ADG, and BEH), and an RCM (J). Applicant has determined that such an embodiment is suitable for some applications. However, Applicant has further determined that the nature of parallelogram structures results in redundant joints, resulting in over-constrained mechanisms. Such redundant joints include joints A, B, D, and E.

[0013] As shown in FIGS. 1B and 1C, each link set remains parallel during operation of the overconstrained parallelogram RCM mechanism. However, imprecision caused by manufacturing imperfections in the mechanism can cause the link mechanism to deviate slightly from parallelism, violating the inherent parallelogram alignment of the joints required for it to be considered redundant. In the case of rigid links, this deviation can constrain the mechanism or add additional forces that can interfere with torque sensing (see, e.g., sensor 110 in FIG. 2B) that may be integrated into the RCM mechanism. See also FIG. 10A, which shows another physical embodiment similar to FIG. 8C, in which joint A has been removed. Such an embodiment can result in an anti-parallel configuration, as shown in FIGS. 10C and 8D. The transition occurs when one ternary link (e.g., BEH) overlaps with a binary link (e.g., CF). This anti-parallel configuration (FIG. 8D) is difficult to use as a therapeutic device because it deviates from the desired rotation about the RCM J.

[0014] However, FIG. 9A includes an embodiment that addresses the shortcomings of the systems of FIGS. 1A and 10A. Specifically, FIG. 9A includes flexures 905 and 906. Each flexure is composed of a ternary link ABC and a binary link CF with the addition of a prismatic joint, resulting in two additional predicted degrees of freedom. Because each flexure only allows motion along a single direction, a parallelogram-based RCM mechanism can manage overconstraints in the system without allowing the mechanism to operate in an anti-parallelogram configuration. Both 1-DOF flexure mechanisms can be integrated into either binary or ternary links, but are positioned so that the directions of motion are not parallel throughout the mechanism's intended range of motion.

[0015] In contrast, FIGS. 10A, 10B, and 10C show a system in which the ternary link of FIG. 9A is replaced with a binary link and the redundant joint is eliminated. Note how the lack of a redundant joint causes a failure at the transition point, causing the RCM mechanism to enter an anti-parallel state (i.e., the parallelogram RCM mechanism assumes an anti-parallelogram configuration). This anti-parallel state is avoided by the embodiment of FIG. 9A, for example. As a result, the RCM mechanism maintains predictable rotation about the remote rotation axis. This predictability is crucial in certain applications, such as robot-based physical rehabilitation. FIGS. 1A-1D show mechanisms that pass through the transition point and do not become constrained or enter an anti-parallel state. However, such systems must have very precise tolerances for such motion. Thus, the flexure-containing embodiments of FIGS. 2A and 9A, for example, avoid anti-parallel states at the transition point while also tolerating possible manufacturing errors / tolerances.

[0016] By incorporating flexures 905 and 906 in FIG. 9A, any movement of the redundant joints out of perfect alignment with the other redundant joints (perhaps due to manufacturing or tolerance errors) is accommodated by the flexures. These flexures can be implemented in either binary or ternary links. See, for example, the ternary links in FIGS. 5C and 5D. The flexure shown in FIG. 3A can be integrated into either ternary links ABC or DEF (labeled on the similar device in FIG. 1B). A flexure such as that shown in FIG. 7B can be implemented in either binary links CF or GH. FIG. 7A shows a binary link without a flexure mechanism. FIG. 5A shows a ternary link without a built-in flexure mechanism. Thus, links that include flexure mechanisms may vary depending on the embodiment.

[0017] However, selecting two single-degree-of-freedom flexure mechanisms helps manage the over-constraint provided to the RCM mechanism when the flexure mechanism directions are not parallel. For example, in FIG. 9B, fixed rotational joints 911 and 912 may be separated from each other by a distance 931. Distance 931 may be outside the desired manufacturing tolerance. Flexure 906 can limit the effect of manufacturing errors by allowing flexibility 906' at joint 914. In FIG. 9D, one or both of members 903 and 904 may be longer or shorter than required by the desired manufacturing tolerance. Flexure 905 can limit the effect of manufacturing errors by allowing vertical flexibility 905' at joint 908. Further examples are shown in FIGS. 2A, 2B, and 6A.

[0018] The flexure-based embodiments described herein ensure that deviations from perfect joint alignment have negligible impact on the overall RCM motion in applications such as physical therapy (where precision requirements for RCM motion are low). Furthermore, the embodiments improve the force sensitivity of the RCM mechanism by significantly reducing forces caused by over-constraints within the mechanism. This improved force sensitivity is crucial for applications such as physical therapy robots.

[0019] Regarding various applications of the embodiments, the RCM movements described herein are useful in medical device applications requiring movement about an anatomical joint or region. These may include rehabilitation exoskeletons, robotic surgical systems, and the like. However, applications may extend to general robotics, and the like. Furthermore, while the embodiments described herein are described with respect to joints of the upper extremities, it will be understood that the embodiments may be configured for use with other joints, such as hip or knee joints, and may have N degrees of freedom (i.e., one DOF, two DOF, three DOF).

[0020] An example of the use of these mechanisms is a wrist mechanism for a rehabilitation robot. In such an application, a parallelogram RCM mechanism generates one rotational degree of freedom along the anatomical forearm pronation / supination axis. A mechanism such as that shown in Figure 1A utilizes two parallelograms that share multiple pivots. This mechanism is over-constrained. As a result, the loads and stresses on the RCM mechanism depend in part on the precision with which the RCM mechanism is manufactured. For example, if links 3 and 4 in Figure 1A were not the same length, the over-constraint would add excess force, torque, and friction to the system, which would be unacceptable in a precision force-sensing application because it could compromise the system's force-sensing capabilities.

[0021] However, the flexures 105, 106 in Figure 2A address this over-constraint problem by introducing two additional degrees of freedom by adding two separate 1-DOF flexure mechanisms that allow the redundant pivots (i.e., rotational joints) to displace independently. By allowing for displacement of the redundant pivots / joints in the parallelogram RCM mechanism, manufacturing errors in the linkage result in pivot / joint displacement rather than force, torque, or friction. The pivot / joint displacement does not have an additional adverse effect on the RCM mechanism.

[0022] The following examples relate to further embodiments.

[0023] Example 1 includes an exoskeleton robotic system, the exoskeleton robotic system including multiple components, including a parallelogram-based remote center of motion (RCM) mechanism (100). The RCM mechanism includes a second ternary link (102), a third ternary link (103), a fourth ternary link (104), a first binary link (117), and a first ternary link (101) coupled to the second binary link. A motor (107) is coupled to the third ternary link, and a sensor (110) is coupled to the fourth ternary link. The first ternary link includes a first flexure (105), the first flexure configured to act in a first direction (105'). The second ternary link includes a second flexure (106), the second flexure configured to act in a second direction (106'). The first direction is not parallel to the second direction.

[0024] 2A-2B. For example, the sensor may include a position sensor, a torque sensor, or a combination thereof. In one embodiment, the sensor 110 is a position sensor and the torque sensor is included in the motor on the joint 111.

[0025] The sensor 110 may include multiple sensors or at least one link that combine or collectively sense factors such as position, torque, etc. In one embodiment, any of the links may include multiple links or at least one link.

[0026] Example 2. The exoskeleton robotic system of Example 1, wherein in response to actuation by the motor, the RCM mechanism is configured to rotate about a remote central axis located within the body of a user of the exoskeleton robotic system.

[0027] Example 3 The exoskeleton robot system of Example 2, wherein the RCM mechanism includes only one degree of freedom. This only degree of freedom is a rotational degree of freedom about a remote central axis. The RCM mechanism does not include a second degree of freedom.

[0028] For example, the embodiment of FIG. 11A has one degree of freedom (DOF). Adding a flexure, such as flexure 105 or 106, is equivalent to adding one joint and one link to each flexure. This ensures that the predicted DOF matches the actual one DOF about the RCM axis. In FIG. 11A, one degree of freedom of the RCM mechanism is rotational. However, there are no degrees of freedom, such as translational or the remaining two rotational degrees of freedom. However, with flexures 105 and 106, the predicted DOF for the embodiment of FIG. 2A is M=3(6+2)-2(8+2)-3(1)=1. Flexures 105 and 106 increase the number of links by two, and flexures 105 and 106 increase the number of joints by two.

[0029] Example 4. The exoskeleton robot system according to any one of Examples 1 to 3, wherein the RCM mechanism is an RCM mechanism including at least two redundant joints.

[0030] Another version of Example 4. The exoskeleton robotic system of any of Examples 1 to 3, wherein the RCM mechanism is a parallelogram-based RCM mechanism including at least two redundant joints, the at least two redundant joints being located on at least two of the first, second, third, and fourth ternary links.

[0031] Example 5. The exoskeleton robot system of any of Examples 1 to 4, wherein the RCM mechanism is not over-constrained.

[0032] Because the features are not over-constrained, manufacturing tolerances are tighter, facilitating easier and more cost-effective manufacturing.

[0033] For example, the translation equation for the RCM mechanism of FIG. 2A (but excluding flexures 105 and 106) is M = 3(6) - 2(8) - 3(1) = -1. However, with the flexures, M = 1. This matches the actual degrees of freedom when explicitly considering that the RCM mechanism rotates around the RCM (hence, the RCM mechanism has one degree of freedom). By convention, an RCM mechanism is defined as not over-constrained because the predicted degrees of freedom (based on the translation equations) match the actual degrees of freedom. Thus, embodiments such as those shown in FIGS. 2A, 6A, and 9A are not over-constrained. These embodiments include redundant joints that prevent the formation of an antiparallelogram. Flexures such as flexures 105 and 106 "free" the system and avoid constraint. This is evident from the translation equation being 1, and the system not being over-constrained by convention. The flexures in embodiments such as Figure 9A are positioned such that their bending directions do not overlap throughout the range of rotation of the mechanism about the RCM. For example, the embodiment of Figure 9A may accommodate a 144° range of motion. Alternate embodiments include placing two flexures on any binary and / or ternary linkage, provided their directions do not run parallel throughout the intended range of motion of the mechanism about the RCM.

[0034] Many embodiments are directed to systems that are not over-constrained, while other embodiments may be over-constrained. See, for example, Figure 1A. By allowing for constrained or unconstrained embodiments, designers can choose how to best manage manufacturing options.

[0035] Example 6. The exoskeleton robot system of any of Examples 1-5, wherein the first binary link includes a bracket. The bracket is coupled to the first ternary link via a first revolute joint (108), and the bracket is coupled to the second ternary link via a second revolute joint (109).

[0036] The bracket may be one of multiple brackets.

[0037] Example 7. The exoskeleton robot system of any of Examples 1 to 5, wherein the first 2-dimensional link includes a bracket. The bracket is coupled to the first 3-dimensional link via a first rotational joint (108), and the bracket is coupled to the second 3-dimensional link via a second rotational joint (109). The third 3-dimensional link is coupled to the first 3-dimensional link via a third rotational joint (113). The third 3-dimensional link is coupled to the second 3-dimensional link via a fourth rotational joint (114). The fourth 3-dimensional link is coupled to the first 3-dimensional link via a fifth rotational joint (115). The fourth 3-dimensional link is coupled to the second 3-dimensional link via a sixth rotational joint (116).

[0038] In one embodiment, each of the six links (101, 102, 103, 104, 117, and 118) may be rigid.

[0039] Example 8. The exoskeleton robot system according to any one of Examples 1 to 7, wherein the first direction is perpendicular to the second direction.

[0040] Another version of Example 8. The exoskeleton robot system of any of Examples 1 to 7, wherein the first direction is not parallel to the second direction throughout the entire range of motion of the RCM mechanism.

[0041] Example 9 The exoskeleton robot system according to any one of Examples 1 to 8, wherein the sensor includes a torque sensor. The motor and the torque sensor are coupled to the RCM mechanism via different rotary joints.

[0042] The torque sensor may be one of a plurality of torque sensors.

[0043] Another version of Example 9. The exoskeleton robot system of any of Examples 1 to 8, further comprising an additional sensor. The additional sensor includes a torque sensor, and the motor and the torque sensor are coupled to the RCM mechanism via a single rotary joint.

[0044] For example, in one embodiment, the motor and torque sensor are coupled to the RCM mechanism through the same rotary joint. In the same embodiment, the position sensor (110) and the motor are coupled to the RCM mechanism through different rotary joints. In one embodiment, both a torque sensor and a position sensor can be included.

[0045] In one embodiment, the motor and the first sensor are coupled to the RCM mechanism via the same rotary joint, and the motor and the second sensor are coupled to the RCM mechanism via a different rotary joint. In one embodiment, the first sensor is a torque sensor and the second sensor is a position sensor. In one embodiment, the second sensor is a torque sensor and the first sensor is a position sensor.

[0046] See, for example, revolute joints 111, 112. Sensors (e.g., encoders, torque sensors, accelerometers) may be used to obtain data regarding the position, angle, acceleration, force (e.g., torque), etc. of one or more joints and / or segments at which the limb may be deployed and / or associated with the mechanical linkages of the exoskeleton.

[0047] The embodiments improve the performance of the torque sensing capabilities of the system (embodiments reduce binding forces) because binding forces are undesirable and inhibit force measurements targeted at the patient.

[0048] Example 10. The exoskeleton robot system according to any one of Examples 1 to 9, wherein the RCM mechanism is a robot shoulder joint or a robot wrist joint.

[0049] Example 11 The exoskeleton robotic system of Example 1, wherein the RCM mechanism is a parallelogram-based RCM mechanism. In response to actuation by the motor, the RCM mechanism is configured to rotate about a central axis located within the body of a user of the exoskeleton robotic system. The RCM mechanism is configured to rotate at least 40° but less than 180°. The rotation range is configured to be at least 40 degrees and less than 180 degrees.

[0050] The range of rotation may vary depending on the length of the link, and other embodiments are not limited to this angle range.

[0051] Another version of Example 11. The exoskeleton robotic system of Example 1, wherein the RCM mechanism is a parallelogram-based RCM mechanism. In response to actuation of the motors, the RCM mechanism is configured to rotate about a central axis located within the body of a user of the exoskeleton robotic system. The RCM mechanism is configured to rotate through a full range of rotation including a transition point.

[0052] Example 11.1 The exoskeleton robotic system of Example 11, wherein the first direction is never parallel to the second direction throughout the entire rotation range.

[0053] Example 12. The exoskeleton robot system of any of Examples 1-11, wherein the first ternary link is disposed primarily in a first plane, the second ternary link is disposed primarily in a second plane, and the first plane is parallel to the second plane.

[0054] Example 1a. An exoskeleton robotic system includes a parallelogram-based remote center of motion (RCM) joint (200). The RCM mechanism includes a first link (201) coupled to a second link (202), a third link (203), and a fourth link (204). A motor (207) is coupled to the third link. A first link of the first, second, third, or fourth links includes a first flexure (205), the first flexure (205) having a first degree of freedom in a first direction (205'). A second link of the first, second, third, or fourth links includes a second flexure (206), the second flexure having a second degree of freedom in a second direction (206'). The first direction is not parallel to the second direction.

[0055] See, for example, Figure 6A. Thus, embodiments are diverse and can include RCM mechanisms comprised of any two flexures on any two links that do not act in parallel.

[0056] Example 2a. The exoskeleton robotic system of Example 1a, wherein the first link is a first ternary link and the second link is a second ternary link.

[0057] Example 2.1a. The exoskeleton robot system of Example 2a, wherein the first flexure is included in either the first or second link, and the second flexure is included in either the third or fourth link.

[0058] For example, the third or fourth link can include any of the links in Figures 5B, 5C, or 5D. See also Figures 6A and 6B. Thus, while the embodiment of Figure 2A includes a flexure in the ternary link, other embodiments include flexures in other links. Figure 6B does not show the hand / wrist directly connected to the joint, but a connector (not shown) may couple the patient's hand / wrist to the joint.

[0059] For example, the third or fourth link can include any of the links of FIG. 9A, such as a binary link including flexure 905.

[0060] Example 2.2a. An exoskeleton robotic system as described in any of Examples 1a-2.1a, wherein in response to actuation by the motors, the RCM mechanism is configured to rotate about a center point located within the body of a user of the exoskeleton robotic system.

[0061] For example, the center point may be located on axis 218 .

[0062] The exoskeleton robotic system of Example 2a, wherein the RCM mechanism includes only one degree of freedom, the one degree of freedom being rotational about a center point. The RCM mechanism does not include a second degree of freedom.

[0063] Example 4a. The exoskeleton robotic system of any of Examples 1a-3a, wherein the RCM mechanism includes at least two redundant joints.

[0064] Another version of Example 4a: The exoskeleton robotic system of any of Examples 1a-3a, wherein the RCM mechanism includes at least two redundant joints, the at least two redundant joints being arranged together on the first link and the second link.

[0065] The flexure mechanisms can be integrated into either binary or ternary links, but are arranged so that their directions of motion are not parallel throughout the mechanism's intended range of motion.

[0066] Example 5a. The exoskeleton robot system according to any one of Examples 1a to 4a, wherein the RCM mechanism is not over-constrained.

[0067] The exoskeleton robot system of any of Examples 1a-5a, further comprising a fifth link. The fifth link includes a bracket. The bracket is coupled to the first link via a first revolute joint (208). The bracket is coupled to the second link via a second revolute joint (209).

[0068] In one embodiment, a bracket such as bracket 317 of Figure 7B can include flexure 306 of Figure 7B, which may eliminate the need for a flexure such as flexure 205 of Figure 6A if each flexure has degrees of freedom parallel to one another. Figure 7A includes a bracket without a flexure.

[0069] Example 7a. The exoskeleton robot system of any of Examples 1a-5a, including a fifth link. The fifth link includes a bracket coupled to the first link via a first revolute joint (208). The bracket is coupled to the second link via a second revolute joint (209). The third link is coupled to the first link via a third revolute joint. The third link is coupled to the second link via a fourth revolute joint. The fourth link is coupled to the first link via a fifth revolute joint (215). The fourth link is coupled to the second link via a sixth revolute joint (216).

[0070] Example 8a. The exoskeleton robot system according to any one of Examples 1a to 7a, wherein in one direction (one orientation), the first direction is orthogonal to the second direction.

[0071] Another version of Example 8a: The exoskeleton robotic system of any of Examples 1a to 7a, wherein the first direction is not parallel to the second direction throughout the entire range of motion of the RCM mechanism.

[0072] Example 9a. The exoskeleton robot system of any of Examples 1a-8a, further comprising a sensor (210), wherein the motor and the sensor are coupled to the RCM mechanism via different rotary joints.

[0073] See, for example, revolute joint 212.

[0074] Another version of Example 9a: The exoskeleton robotic system of any of Examples 1a-8a, further comprising a sensor, wherein the motor and the sensor are coupled to the RCM mechanism via a single revolute joint.

[0075] Example 10a. The exoskeleton robot system according to any one of Examples 1a to 9a, wherein the RCM mechanism is a robot shoulder joint or a robot wrist joint.

[0076] The exoskeleton robotic system of Example 1a, wherein in response to actuation by the motor, the RCM mechanism is configured to rotate about a central axis located within a body of a user of the exoskeleton robotic system, the RCM mechanism being configured to rotate within a rotation range of 40° or greater and less than 360°.

[0077]

[0041] In another version of Example 11a, the exoskeleton robotic system of Example 1a, wherein the RCM mechanism is a parallelogram-based RCM mechanism. In response to actuation by the motors, the RCM mechanism is configured to rotate about a central axis located within a body of a user of the exoskeleton robotic system. The RCM mechanism is configured to rotate through a full range of rotation including a transition point.

[0078] Example 11.1a. The exoskeleton robotic system of Example 11a, wherein the first direction is never parallel to the second direction throughout the entire rotation range.

[0079] Example 12a. An exoskeleton robot system according to any of Examples 1a to 11a, wherein the first link is a ternary link arranged primarily in a first plane, and the second link is a ternary link arranged primarily in a second plane, and the first plane is parallel to the second plane.

[0080] Example 1b. An exoskeleton robotic system includes a remote center of motion (RCM) robotic joint (100). The RCM mechanism includes a first link (101) coupled to a second link (102), a third link (103), and a fourth link (104). A motor (107) is coupled to the third link. The first link includes a first plate having three pivot joints, and the second link includes a second plate having three pivot joints. The first link includes a first elastic member (105) configured to flex in a first direction (105') but not in a second direction (106'). The second link includes a second elastic member (106) configured to flex in a second direction but not in the first direction. The first direction is not parallel to the second direction.

[0081] Example 2b. The exoskeleton robotic system of Example 1b, wherein in response to actuation by the motor, the RCM mechanism is configured to rotate about a center point located within the body of a user of the exoskeleton robotic system.

[0082] The exoskeleton robotic system of Example 2b, wherein the RCM mechanism includes only one degree of freedom, the one degree of freedom being rotational about a center point. The RCM mechanism does not include a second degree of freedom.

[0083] Example 4b. The exoskeleton robotic system of any of Examples 1b-3b, wherein the RCM mechanism includes at least two redundant joints.

[0084] Another version of Example 4. The exoskeleton robot system of any of Examples 1 to 3, wherein the RCM mechanism includes at least two redundant joints, and the at least two redundant joints are included in the first link and the second link.

[0085] Example 5b. The exoskeleton robotic system of any of Examples 1b-4b, wherein the RCM mechanism is not over-constrained.

[0086] The exoskeleton robot system of any of Examples 1b-5b, further comprising a bracket (117) coupled to the first link via a first pivot joint (108) of the first link's three pivot joints, and a bracket coupled to the second link via a first pivot joint (109) of the second link's three pivot joints.

[0087] Example 7b. The exoskeleton robot system of any of Examples 1b-5b, further comprising a bracket (117). The bracket is coupled to a first ternary link via a first pivot joint (108) of the first link's three pivot joints. The bracket is coupled to a second ternary link via a first pivot joint (109) of the second link's three pivot joints. The third link is coupled to the first link via a second pivot joint (113) of the first link's three pivot joints. The third link is coupled to the second link via a second pivot joint (114) of the second link's three pivot joints. The fourth link is coupled to the first link via a third pivot joint of the first link's three pivot joints. The fourth link is coupled to the second link via a third pivot joint of the first link's three pivot joints.

[0088] Example 8b. The exoskeleton robotic system of any of Examples 1b-7b, wherein the first direction is orthogonal to the second direction.

[0089] Example 9b. The exoskeleton robotic system of any of Examples 1b-8b, further comprising a sensor (110), wherein the motor and the sensor are coupled to the RCM mechanism via different pivot joints.

[0090] See, for example, revolute joints 111 and 112.

[0091] Another version of Example 9b: The exoskeleton robotic system of any of Examples 1b-8b, further comprising a sensor (110), wherein the motor and sensor are coupled to the RCM mechanism via a single pivot joint.

[0092] Example 10b. The exoskeleton robot system of any of Examples 1b-9b, wherein the RCM mechanism is a robot shoulder joint or a robot wrist joint.

[0093] The exoskeleton robotic system of Example 1b, wherein in response to actuation of the motors, the RCM mechanism is configured to rotate about a center point located within a body of a user of the exoskeleton robotic system, the RCM mechanism being configured to rotate within a rotation range of greater than or equal to 40° and less than 360°.

[0094] The exoskeleton robot system of any of Examples 1b-11b, wherein the first link is disposed primarily within a first plane, the second link is disposed primarily within a second plane, and the first plane is parallel to the second plane.

[0095] Example 1c. The exoskeleton robotic system includes a parallelogram-based remote center of motion (RCM) joint (900). The RCM mechanism includes a first link (901) coupled to a second link (902), a third link (903), and a fourth link (904). A motor (907) is coupled to the third link. A first link of the first, second, third, or fourth links includes a first flexure (905). The first flexure includes a first degree of freedom in a first direction (905'). A second link of the first, second, third, or fourth links includes a second flexure (906), which includes a second degree of freedom in a second direction (906'). The first direction is not parallel to the second direction.

[0096] See, for example, Figures 9A-9G.

[0097] Example 2c. The exoskeleton robotic system of Example 1c, wherein the first link is a first ternary link and the second link is a second ternary link.

[0098] Example 2.1c. The exoskeleton robotic system of Example 2c, including a fifth link (917) coupled to the first link. The first flexure is included in either the first link or the second link. The second flexure is included in the fifth link.

[0099] Example 2.2c. An exoskeleton robotic system as described in any of Examples 1c to 3c, wherein in response to actuation by the motor, the RCM mechanism is configured to rotate around an axis (918) located within the body of a user of the exoskeleton robotic system.

[0100] The exoskeleton robotic system of Example 2c, wherein the RCM mechanism includes only one degree of freedom, which is a rotational degree of freedom about a center point. The RCM mechanism does not include a second degree of freedom.

[0101] Example 4c. The exoskeleton robotic system of any of Examples 1c-3c, wherein the RCM mechanism includes at least two redundant joints.

[0102] Another version of Example 4c: The exoskeleton robotic system of any of Examples 2.1c-3c, wherein the RCM mechanism includes at least two redundant joints, the at least two redundant joints being included in two of the first, second, third, fourth, or fifth links.

[0103] Example 5c. The exoskeleton robot system of any of Examples 1c-4c, wherein the RCM mechanism is not over-constrained.

[0104] The exoskeleton robotic system according to Example 2.1c, wherein the fifth link includes a bracket. The bracket is coupled to the first link via a first revolute joint (908). The bracket is coupled to the second link via a second revolute joint (909).

[0105] Example 7c. The exoskeleton robotic system according to Example 2.1c, wherein the fifth link includes a bracket. The bracket is coupled to the first link via a first revolute joint (908). The bracket is coupled to the second link via a second revolute joint (909). The third link is coupled to the first link via a third revolute joint (913). The third link is coupled to the second link via a fourth revolute joint (914). The fourth link is coupled to the first link via a fifth revolute joint (915). The fourth link is coupled to the second link via a sixth revolute joint (916).

[0106] Example 8c. The exoskeleton robot system according to any one of Examples 1c to 7c, wherein in one direction (one orientation), the first direction is perpendicular to the second direction.

[0107] Another version of Example 8c: The exoskeleton robotic system of any of Examples 1c to 7c, wherein the first direction is not parallel to the second direction throughout the entire range of motion of the RCM mechanism.

[0108] Example 9c. The exoskeleton robotic system of any of Examples 1c-8c, further comprising a sensor (910), wherein the motor and the sensor are coupled to the RCM mechanism via different revolute joints.

[0109] See, for example, revolute joints 911 and 912.

[0110] Another version of Example 9c: The exoskeleton robotic system of any of Examples 1c to 8c, including a sensor, wherein the motor and the sensor are coupled to the RCM mechanism via a single revolute joint.

[0111] Example 10c. The exoskeleton robot system of any of Examples 1c to 9c, wherein the RCM mechanism is a robot wrist joint.

[0112] The exoskeleton robotic system of Example 1c, wherein in response to actuation of the motors, the RCM mechanism is configured to rotate about a central axis (918) located within the body of a user of the exoskeleton robotic system, and the RCM mechanism is configured to rotate within a rotation range of 40° or more but less than 360°.

[0113]

[0041] Another version of Example 11c. The exoskeleton robotic system of Example 1c, wherein the RCM mechanism is a parallelogram-based RCM mechanism. In response to actuation of the motors, the RCM mechanism is configured to rotate about a central axis located within a user's body of the exoskeleton robotic system. The RCM mechanism is configured to rotate through a full range of rotation including a transition point.

[0114] Example 11.1c. The exoskeleton robotic system according to Example 11c, wherein the first direction is never parallel to the second direction throughout the entire rotation range.

[0115] The exoskeleton robot system of any of Examples 1c to 11c, wherein the first link is disposed primarily in a first plane, the second link is disposed primarily in a second plane, and the first plane is parallel to the second plane.

[0116] The above description of embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the form disclosed. Although this description and the claims include terms such as left, right, top, bottom, above, below, first, and second, these terms are used for descriptive purposes only and should not be construed as limiting. For example, terms indicating relative vertical position refer to a case in which one side of a substrate is the "top" surface of the substrate. A substrate may be oriented in any practical manner, and the "top" side of a substrate may be lower than the "bottom" side in a standard Earth coordinate system and still be included within the meaning of the term "top." The term "top," as used herein (including in the claims), does not imply that a first layer is "above" or in direct contact with a second layer, unless otherwise specified. There may be a third layer or other structure on the first layer between the first and second layers. The embodiments of the devices or articles described herein may be manufactured, used, or shipped in various positions and orientations. Those skilled in the relevant art will appreciate that many modifications and variations are possible in light of the above teachings. Those skilled in the art will recognize various equivalent combinations and alternatives for the various components shown in the figures. Accordingly, it is intended that the scope of the invention be limited not by this detailed description, but rather by the appended claims.

Claims

1. An exoskeleton robot system, the exoskeleton robot system comprising: A parallelogram-based remote center of motion (RCM) mechanism (100) including a second ternary link (102), a third ternary link (103), a fourth ternary link (104), a first binary link (117), and a first ternary link (101) coupled to the second binary link; a motor (107) coupled to the third ternary link; a sensor (110) coupled to the fourth ternary link; (a) the first ternary link includes a first flexure (105), the first flexure configured to act in a first direction (105'); (b) the second ternary link includes a second flexure (106), the second flexure configured to act in a second direction (106'); and (c) the first direction is not parallel to the second direction. Exoskeleton robotic system.

2. The exoskeleton robotic system of claim 1 , wherein in response to actuation of the motor, the RCM mechanism is configured to rotate about a remote central axis located within a user of the exoskeleton robotic system.

3. the RCM mechanism includes only one degree of freedom; the one degree of freedom is a rotational degree of freedom about the remote central axis; The exoskeleton robotic system of claim 2 , wherein the RCM mechanism does not include a second degree of freedom.

4. The exoskeleton robot system according to claim 1 , wherein the RCM mechanism is an RCM mechanism including at least two redundant joints.

5. The exoskeleton robot system of claim 1 , wherein the RCM mechanism is not over-constrained.

6. the first dual link includes a bracket; the bracket is coupled to the first ternary link via a first revolute joint (108); The exoskeleton robot system of claim 1 , wherein the bracket is coupled to the second ternary link via a second revolute joint (109).

7. the first dual link includes a bracket; the bracket is coupled to the first ternary link via a first revolute joint (108); The bracket is coupled to the second ternary link via a second revolute joint (109); the third ternary link is coupled to the first ternary link via a third revolute joint (113); the third ternary link is coupled to the second ternary link via a fourth revolute joint (114); the fourth ternary link is coupled to the first ternary link via a fifth revolute joint (115); The exoskeleton robotic system of claim 1 , wherein the fourth ternary link is coupled to the second ternary link via a sixth revolute joint (116).

8. The exoskeleton robotic system of claim 1 , wherein the first direction is orthogonal to the second direction.

9. the sensor includes a torque sensor; The exoskeleton robotic system of claim 1 , wherein the motor and the torque sensor are coupled to the RCM mechanism via different revolute joints.

10. The exoskeleton robot system according to claim 1 , wherein the RCM mechanism is a robot shoulder joint or a robot wrist joint.

11. the RCM mechanism is a parallelogram-based RCM mechanism; In response to actuation of the motor, the RCM mechanism is configured to rotate about a central axis located within a user of the exoskeleton robotic system; The exoskeleton robotic system of claim 1 , wherein the RCM mechanism is configured to rotate within a rotation range of 40° or more and less than 180°.

12. The exoskeleton robotic system of claim 11 , wherein the first direction is never parallel to the second direction throughout the range of rotation.

13. the first ternary link is disposed primarily in a first plane; the second ternary link is disposed primarily in a second plane; The exoskeleton robotic system of claim 1 , wherein the first plane is parallel to the second plane.

14. An exoskeleton robot system, the exoskeleton robot system comprising: a parallelogram-based remote center of motion (RCM) joint (200), comprising a first link (201) coupled to a second link (202), a third link (203), and a fourth link (204); a motor (207) coupled to the third link; (a) a first link of the first, second, third, or fourth link includes a first flexure (205), the first flexure (205) including a first degree of freedom in a first direction (205′); (b) a second link of the first, second, third, or fourth link includes a second flexure (206), the second flexure including a second degree of freedom in a second direction (206'); (c) the first direction is not parallel to the second direction.

15. The exoskeleton robotic system of claim 14 , wherein the first link is a first ternary link and the second link is a second ternary link.

16. the first flexure is included in one of the first or second links; The exoskeleton robotic system of claim 15 , wherein the second flexure is included in one of the third or fourth links.

17. 17. The exoskeleton robotic system of claim 14, wherein in response to actuation by the motors, the RCM joints are configured to rotate about a center point located within a user of the exoskeleton robotic system.

18. the RCM joint includes only one degree of freedom; the one degree of freedom is a rotational degree of freedom about the center point; The exoskeleton robotic system of claim 17 , wherein the RCM joint does not include a second degree of freedom.

19. The exoskeleton robotic system of claim 14 , wherein the RCM joint includes at least two redundant joints.

20. The exoskeleton robotic system of claim 14 , wherein the RCM joints are not over-constrained.

21. a fifth link; the fifth link includes a bracket; The bracket is coupled to the first link via a first revolute joint (208); 21. The exoskeleton robotic system of any one of claims 14 to 20, wherein the bracket is coupled to the second link via a second revolute joint (209).

22. a fifth link; the fifth link includes a bracket; The bracket is coupled to the first link via a first revolute joint (208); The bracket is coupled to the second link via a second revolute joint (209); the third link is coupled to the first link via a third rotational joint; the third link is coupled to the second link via a fourth rotational joint; the fourth link is coupled to the first link via a fifth revolute joint (215); 21. The exoskeleton robotic system of any one of claims 14 to 20, wherein the fourth link is coupled to the second link via a sixth revolute joint (216).

23. 23. The exoskeleton robotic system of claim 14, wherein in one direction, the first direction is orthogonal to the second direction.

24. a sensor (210); 24. The exoskeleton robotic system of claim 14, wherein the motors and the sensors are coupled to the RCM joints via different revolute joints.

25. The exoskeleton robotic system of any one of claims 14 to 24, wherein the RCM joint is a robotic shoulder joint or a robotic wrist joint.

26. In response to actuation by the motor, the RCM joint is configured to rotate about a central axis located within a user of the exoskeleton robotic system; The exoskeleton robotic system of claim 14 , wherein the RCM joint is configured to rotate within a rotation range of 40° or more but less than 360°.

27. 27. The exoskeleton robotic system of claim 26, wherein the first direction is never parallel to the second direction throughout the entire range of rotation.

28. the first link is a ternary link disposed primarily in a first plane; the second link is a ternary link disposed primarily in a second plane; 27. The exoskeleton robotic system of claim 14, wherein the first plane is parallel to the second plane.

29. An exoskeleton robot system, the exoskeleton robot system comprising: A remote center of motion (RCM) robotic joint (100), comprising a first link (101) coupled to a second link (102), a third link (103), and a fourth link (104); a motor (107) coupled to the third link; (a) the first link includes a first plate having three pivot joints, and the second link includes a second plate having three pivot joints; (b) the first link includes a first elastic member (105) configured to bend in a first direction (105') but not in a second direction (106'); (c) the second link includes a second elastic member (106) configured to flex in the second direction but not flex in the first direction; (d) the first direction is not parallel to the second direction; Exoskeleton robotic system.

30. 30. The exoskeleton robotic system of claim 29, wherein in response to actuation by the motors, the RCM joints are configured to rotate about a center point located within a user of the exoskeleton robotic system.

31. the RCM joint includes only one degree of freedom; the one degree of freedom is a rotational degree of freedom about the center point; 31. The exoskeleton robotic system of claim 30, wherein the RCM joint does not include a second degree of freedom.

32. 32. The exoskeleton robotic system of any one of claims 29 to 31, wherein the RCM joint includes at least two redundant joints.

33. 33. The exoskeleton robotic system of any one of claims 29 to 32, wherein the RCM joints are not over-constrained.

34. a bracket (117), The bracket is coupled to the first link via a first pivot joint (108) of the first link's three pivot joints; 34. The exoskeleton robotic system of any one of claims 29 to 33, wherein the bracket is coupled to the second link via a first pivot joint (109) of three pivot joints of the second link.

35. a bracket (117), The bracket is coupled to the first link via a first pivot joint (108) of the first link's three pivot joints; The bracket is coupled to the second link via a first pivot joint (109) of the second link's three pivot joints; The third link is coupled to the first link via a second pivot joint (113) of the three pivot joints of the first link; the third link is coupled to the second link via a second pivot joint (114) of the three pivot joints of the second link; the fourth link is coupled to the first link via a third pivot joint of the three pivot joints of the first link; 34. The exoskeleton robotic system of any one of claims 29 to 33, wherein the fourth link is coupled to the second link via a third pivot joint (116) of the three pivot joints of the first link.

36. 36. The exoskeleton robotic system of any one of claims 29 to 35, wherein the first direction is orthogonal to the second direction.

37. a sensor (110), 37. The exoskeleton robotic system of any one of claims 29 to 36, wherein the motors and the sensors are coupled to the RCM joints via different pivot joints.

38. 38. The exoskeleton robotic system of any one of claims 29 to 37, wherein the RCM joint is a robotic shoulder joint or a robotic wrist joint.

39. In response to actuation by the motor, the RCM joint is configured to rotate about a center point located within a user of the exoskeleton robotic system; 30. The exoskeleton robotic system of claim 29, wherein the RCM joint is configured to rotate within a rotation range of 40 degrees or more but less than 360 degrees.

40. the first link is disposed primarily in a first plane; the second link is disposed primarily in a second plane; 40. The exoskeleton robotic system of any one of claims 29 to 39, wherein the first plane is parallel to the second plane.

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