Orthopaedic joint device and method for controlling same

Abstract

The invention relates to an orthopaedic joint device having an upper part (10) and a lower part (20) which are mounted on one another to pivot with respect to one another about a pivot axis (15) and at least one resistance device (30) which is arranged between the upper part (10) and the lower part (20), the resistance device (30) being designed to influence a pivoting or pivotability of the upper part (10) relative to the lower part (20), wherein a motorised drive (60) and at least one force-storage means (90) are arranged between the upper part (10) and the lower part (20), which are designed and configured to effect, support or prevent a pivoting or pivotability of the upper part (10) relative to the lower part (20).

Description

[0001] Orthopaedic joint device and method for its control

[0002] The invention relates to an orthopedic joint device comprising an upper part and a lower part, which are mounted relative to one another so as to be pivotable about a pivot axis, and at least one resistance device arranged between the upper part and the lower part. The resistance device is designed to influence the pivoting or pivotability of the upper part relative to the lower part. The invention also relates to a method for controlling such an orthopedic joint device.

[0003] Orthopedic joint devices include, in particular, orthoses, exoskeletons, or prostheses that comprise an upper part and a lower part articulated to it. In orthoses and exoskeletons, the upper and lower parts are attached to a still-existing limb, for example, by shells, straps, belts, cuffs, or other fastening devices. Orthoses and exoskeletons can guide movements, limit pivoting about a pivot axis, prevent pivoting movements, or support or fix the alignment of limbs relative to one another. Furthermore, orthoses can be equipped with resistance devices to influence a pivoting movement about the pivot axis. The resistance devices can be equipped with a control system so that, depending on sensor data, a modified resistance can be provided in the flexion and / or extension directions.It is also known to assign energy storage devices to the upper or lower part so that movement support can be achieved by releasing the stored energy from the energy storage device.

[0004] Prostheses replace a missing or no longer existing limb and serve to provide functionality that is as close as possible to that of the natural limb. In addition, prostheses serve to provide the most natural appearance possible for the prosthetic user. A prosthetic upper part is designed, for example, as a prosthetic socket or as a component attached to a prosthetic socket, where the prosthetic socket serves to secure it to a limb or limb stump. The prosthetic joint, for example a prosthetic knee joint, a prosthetic ankle joint, or a prosthetic elbow joint, connects the upper part to a lower part, which in turn may have further prosthetic components, such as a lower leg tube, a prosthetic foot, or a prosthetic hand.

[0005] Particularly in orthoses, exoskeletons, and prostheses of the lower extremities, but also of the upper extremities, dampers, in particular hydraulic dampers or other resistance devices, are arranged between the upper and lower parts. These dampers provide different resistances in individual states or movement situations based on sensor data. Such resistance devices are often designed as linear actuators that provide a defined resistance to a flexion and / or extension movement. The resistance is changed by changing the position of valves. When the flow cross-section is reduced, the corresponding resistance to a movement increases. Passively damped, especially passively hydraulically damped prostheses or orthoses work purely dissipatively. Energy is extracted from the movement of the upper part relative to the lower part, which can generate very high moments or forces.At the same time, passive damping exhibits very low resistance in an open state, for example, when no valves are closed or throttles are activated. The operating range of such an orthosis or prosthesis is limited in that no energy can be directed into the movement to support it, actively counteract it, or initiate a change from a static state.

[0006] In addition, orthoses, exoskeletons, and prostheses with motor drives are known from the state of the art, so-called active orthoses or prostheses, in which a movement is initiated, supported, or decelerated by activating, deactivating, or modulating the drive. For this purpose, stored electrical energy from a battery or accumulator is converted into the actuator. The motor drives also serve to influence the movement behavior between the components of the orthosis or prosthesis within the framework of a generator circuit, for example, to decelerate a pivoting movement and thereby charge or support the energy storage device. Deceleration can also be achieved in short-circuit operation. In this operating mode, the energy extracted from the movement is converted into heat within the drive. The maximum achievable moments or forces that can be achieved by a motor drive are limited.

[0007] EP 2 535 024 A1 describes a prosthetic leg with a knee element connecting an upper part to an elongated lower leg part to enable relative movement. A serial elastic actuator is arranged between the knee element and the lower leg part and is configured to exert a torque on the knee element to effect relative movement between the knee element and the lower leg element. The serial elastic actuator comprises a motor coupled to an elastic device.

[0008] DE 102018 126 324 A1 describes an orthopedic joint comprising a first component, a second component pivotably mounted on the first component about a pivot axis, and an actuator for pivoting the first component relative to the second component in at least one direction. The actuator is detachably mounted on a medial or lateral side of the first component or the second component. The joint may comprise at least one damper configured and arranged to damp pivoting of the first component relative to the second component. The actuator may comprise an elastic element and / or a serial elastic actuator and / or a parallel elastic actuator.

[0009] The article "A Comparison of Parallel- and Series Elastic Elements in an Actuator for Mimicking Human Ankle Joint in Walking and Running" by Martin Grimmer, Mahdy Eslamy, Stefan Gliech, and Andre Seyfarth, published at the IEEE International Conference on Robotics and Automation in 2012, discusses the reduction of peak power and energy consumption of actuators through the use of elastic elements in prostheses. With current commercially available motor technologies, it is not possible to mimic the behavior of a human ankle for higher speeds and during walking with a single motor solution using a series elastic actuator. Using a parallel elastic actuator, the required peak power of the drive can be further reduced. Combining both elastic actuators leads to a further reduction.

[0010] In the article “Effects of Unidirectional Parallel Springs on Required Peak Power and Energy in Powered Prosthetic Ankles: Comparison between Different Active Actuation Concepts” by Mahdy Eslamy, Martin Grimmer and Andre Seyfarth, pp. 2406 to 2412, Proceedings of the 2012 IEEE International Conference on Robotics and Biomimetics, December 11-14, 2012, Guangzhou, China, the same problem is discussed and a concept of a motor with two energy storage devices, one in series and one in parallel, is presented.

[0011] The object of the present invention is to provide an orthopaedic joint device and a method for controlling the same, with which the orthopaedic joint device can be operated reliably and with a low weight over the largest possible working range.

[0012] This object is achieved by an orthopedic joint device having the features of the main claim and a method for controlling such an orthopedic joint device having the features of the independent claim. Advantageous embodiments and further developments of the invention are disclosed in the dependent claims, the description, and the figures.

[0013] The orthopaedic joint device with an upper part and a lower part, which are mounted on one another so as to be pivotable relative to one another about a pivot axis, and with at least one resistance device which is arranged between the upper part and the lower part, wherein the resistance device is designed to influence a pivoting or pivotability of the upper part relative to the lower part, furthermore has a motor drive and at least one energy accumulator arranged between the upper part and the lower part, which are designed and configured to effect, assist or hinder a pivoting of the upper part relative to the lower part.While the resistance device, in particular a hydraulic damper, a pneumatic system, a friction brake, a magnetorheological resistance device and / or a locking mechanism, can dissipate a high degree of kinetic energy between the upper and lower parts with a comparatively low weight or simply blocks relative movement between the upper and lower parts, for example by blocking the fluid connection between the chambers, it is possible to actively apply a driving or braking torque about the pivot axis using the motor drive or the energy storage device. The motor drive is designed, for example, as an electric motor and is optionally coupled to the upper and lower parts via a gear system. The gear system can be designed, for example, as a spindle drive, gear drive, lever drive, cable drive, friction gear or another type of gear.If an existing movement is to be supported, the resistance by the resistance device is reduced, if possible, to the minimum value specific to the resistance device, e.g. 0, so that the drive only has to generate the torque to overcome the residual resistance or internal friction and to accelerate the lower part relative to the upper part. If the orthopedic joint device is attached to an orthosis, the respective limb moves with the upper or lower part. In addition, there is an energy storage device in which otherwise dissipated kinetic energy can be stored as potential energy, particularly in order to be able to cope with peak loads. Motor drives can only achieve a limited number of revolutions or linear speeds. Depending on the design, this limit is below the maximum movement speed of the energy storage device.While motor drives operate comparatively slowly, an energy storage device can be released in such a way that the desired amount of energy is supplied to the joint device at the desired time in order to provide a driving or braking moment around the pivot axis.

[0014] By combining at least one resistance device with at least one drive and at least one energy storage device, the installation space for the active drive can be kept small, as the energy storage device and the resistance device compensate for the structural weaknesses of an electric drive. The operating range of the orthopedic joint device is expanded overall, and the drive requires less energy, allowing the drive's supply components, especially the energy storage devices, to be smaller and lighter. The mechanical loads on the drive components are also reduced by the absorption of forces and moments via the resistance device and, if applicable, the energy storage device, thereby improving the overall durability of the system.

[0015] In a further development, the at least one resistance device and / or the energy accumulator are designed to be adjustable, in particular depending on current load variables, conditions or expected movement sequences, which are determined in particular via sensors. The sensor values ​​determined by the sensors are fed to a controller and evaluated therein. Based on the evaluation, the settings within the resistance device and / or the energy accumulator are changed, e.g. those of the valves or throttles of the hydraulic damper, the contact pressure of the braking device, the magnetic field of the magnetorheological device and the like. The movement resistance of a hydraulic or pneumatic damper can be changed via switching valves or proportional valves. Likewise, the storage of energy or the release of energy from the energy accumulator can be initiated based on the sensor values ​​and their evaluation.In particular, the energy storage device can be locked, e.g. in order to be able to charge the energy storage device successively and to retrieve the stored energy at the desired time.

[0016] In one embodiment, the resistance device has a housing with a cylinder in which a piston is displaceably mounted and divides the cylinder into two chambers, between which at least one fluidic connection is formed, in which at least one adjustable valve is arranged, which is designed as a switching valve with at least two switching positions, wherein at least one switching position is a partially open switching position. A partially open switching position is in particular a switching position that deviates from a fully open or fully closed switching position, wherein a fully open or closed switching position can be the second switching position. The two switching positions can also be the fully open and the fully closed switching position.In purely passive orthopedic joint devices, the relative movement of the upper and lower parts is influenced by converting kinetic energy into thermal energy. To adapt the influence to the specific movement behavior or movement pattern, the valve must be designed as a proportional valve and a comparatively complex control system with a servomotor for each valve is required. Active orthopedic joint devices with a motor solely controlling relative movement require a large motor or large gears to fully and independently absorb the resulting forces.The claimed orthopedic device makes it possible to significantly simplify the complex structure of purely passive resistance devices or purely active actuators for orthopedic joint devices, without sacrificing the ability to respond precisely and appropriately to the respective movement situations or conditions. The switching valves switch between several discrete states, at least between two switching positions, for example, fully open or fully closed, and a partially open or partially closed switching position. This is achieved, for example, by sliding or simply switching between the respective positions, for example, by activating a coil, without the need to activate motors.This makes it possible to lock the orthopedic joint device against flexion and extension in a fully closed position, and to set a frequently required movement resistance in a partially open switching position. To allow modification of the corresponding resistance around this pivoting resistance, a motor drive is assigned to the orthopedic joint device or connected to it to influence the pivoting movement. The motor drive can be activated at specific times or in specific states or positions, either as a drive to introduce additional energy into the movement, or as a brake to convert kinetic energy into heat energy or electrical energy in a generator operation.If the motor drive is activated as a drive, the existing movement can be supported or used to counteract the movement. It is also possible to move one of the components of the orthopedic joint device from a static state. In either case, an additional torque is generated in the joint, either a driving or a braking or damping torque. The motor drive can be used to fine-tune the resistance behavior or damping behavior of the resistance device, particularly in a hydraulic damper configuration, which can be designed as a linear damper or a rotary damper.

[0017] In one embodiment, the valve is designed as a multi-way valve with a closed switching position, an open switching position, and at least one partially open switching position. In one embodiment of the multi-way valve as a 3-way valve, the hydraulic damper can be moved along with a pivoting movement in the open switching position essentially without damping, so that a negligible resistance moment is generated in the joint. In this switching position, the orthopedic joint device is operated as an active joint when the actuator is activated to exert a moment in the joint, either as a drive or as a brake. In the fully locked switching position, a relative displacement from the upper part to the lower part is not possible.In the partially open switching position, which can be adjustable with regard to the degree of opening, the actuator counteracts or supports the resistance of the resistance device during appropriate operation.

[0018] In one embodiment, the partially open switching position is reduced by a certain percentage compared to the fully open switching position in terms of the flow cross-section, so that a preset output damping is present between a fully open and fully closed state, i.e. greater than the minimum damping in the fully open state and less than the maximum damping in the closed state. The movement behavior is then changed around this position via the actuator. The additional drive now makes it possible to influence the preset movement resistance in the prosthetic joint or orthotic joint. The resistance can be influenced in such a way that it can be weakened or increased within a certain range by appropriately controlling the drive.Likewise, the resistance curve over time, position, speed or acceleration of a patient component or limb can be adapted. The flow cross-section can be adapted to the respective application or user. For example, if experience shows that a certain damping torque or damping force must be applied very frequently, such as a certain high level of damping against flexion in an artificial knee joint, a corresponding reduction in the flow cross-section can be provided for the partially open switch position. If predominantly low levels of damping or resistance are to be applied by the resistance device, particularly in the form of a hydraulic damper, it is advisable to increase the flow cross-section accordingly and set it to the value that is likely to be used most frequently.

[0019] In a further embodiment, the drive or motor is arranged in parallel with a system of one or more passive resistance devices. Furthermore, this system can also have one or more energy storage devices that operate in parallel or in series with the resistance device. Each energy storage device can have an adjustment mechanism to influence the characteristics of the energy storage device. At least one of the multiple resistance devices has an adjustment mechanism to adjust the resistance. This mechanism can be adjusted via an actuator. The actuator can be adjusted automatically based on sensor values. With the system mentioned, various advantageous variants for controlling the drive or motor can be implemented.

[0020] An adjustable resistance device, for example, has an adjustment mechanism that requires a time period T1 to increase or decrease the resulting resistance in the joint to a desired value. The time period T1 is longer than the time period T2 in which the corresponding resistance must be set in order to achieve the desired behavior of the orthopedic joint device. The response time of the drive T3 to apply resistance is significantly faster than T1 and thus T3 is shorter than T1. In order to approximate the overall behavior to the duration T2, the drive can be controlled so that the resistance is applied by the drive during T1. The drive resistance is adjusted in such a way that the drive only supplies the difference between the desired resistance in the orthopedic joint device and the resistance applied by the resistance device.This allows the resulting travel time to be virtually reduced. The overall system behaves as if it had the travel time T3.

[0021] The system described offers further advantages. Depending on the design of the resistance device, especially as an adjustable hydraulic damper, which can be fully lockable, it can absorb large forces or moments without consuming electrical energy. This is particularly advantageous for isometric or very slow movements. In contrast, drives in these operating states require a lot of electrical energy to achieve the same behavior. The sensors built into the system can detect such conditions. As soon as the resistance device reaches the set resistance, the drive is completely deactivated. The resistance device now holds the entire load, and the drive requires no energy.

[0022] Another form of drive control arises from the fact that an electric drive can be operated as a resistance device, which converts mechanical energy into electrical energy within a certain range of resistance torques or forces and speeds. In contrast, passive resistance devices convert mechanical energy into heat. This energy is lost or causes problems due to a rise in temperature within the system.

[0023] The flow of mechanical energy in the joint device can be controlled by adjusting the resistance of the passive resistance device and the resistance of the drive acting as a resistance device. This makes it possible to direct more mechanical energy into the drive during movement states in which the drive can generate electrical energy. This reduces the energy input into the passive resistance device, thus also reducing heating. In addition, a portion of the mechanical energy directed into the drive can be converted into electrical energy by the drive and stored in the electrical energy storage device, which in turn can extend the service life of the orthopedic joint device or reduce the size of the required electrical energy storage device.In one embodiment, the drive is designed as an electric motor coupled to the upper or lower part via a gear mechanism. The gear mechanism makes it possible to generate comparatively large torques in the joint around the pivot axis, even with small motors, in order to influence the relative movement between the upper and lower parts or to displace the upper part relative to the upper part. The gear mechanism can be designed, for example, as a spindle drive, gear drive, lever drive, cable drive, friction gear, or another type of gear mechanism.

[0024] In one embodiment, a controller is assigned to the drive and / or the resistance device and / or the energy storage device, which controller has a data processing device for processing sensor data. The data processing device has the necessary components, for example a microprocessor, a memory device, an integrated circuit, or the like, and is coupled to a power supply that enables the controller as a component to process and / or store data. The controller is coupled to at least one sensor and is configured to activate, deactivate, and / or modulate the drive and / or the resistance device and / or the energy storage device based on the sensor values. The controller as a component has interfaces via which the controller is supplied with data from the sensors.The interfaces can be wireless or wired, for example, as a transmitter-receiver device, a connector, or permanent contacts. The sensors can be connected to the controller wirelessly or wired.

[0025] A further development provides for the resistance device, energy storage device, and drive to be designed as a modular unit and secured together at the attachment points on the upper and lower sections. This makes it possible to have different modifications and designs of drives, resistance devices, or energy storage devices ready as part of a prefabricated unit, so that these units or modules can then be mounted as a whole on the orthopedic joint device. The system can also be designed as a logical unit, with a shared control system including sensors for the resistance device, energy storage device, and drive. The advantage of this is a simplified interface for controlling the system. The shared control system only needs to specify the behavior of the orthopedic joint device. The control of the energy flows within the mechanical system takes place within the logical unit.This shortens the development time of the behavioral control of the superimposed control.

[0026] In a further development, the energy accumulator is designed as a spring, in particular a compression spring, or as a pressure accumulator, in particular as a pneumatic or hydraulic pressure accumulator, which is integrated into the resistance device. A spring in the form of a compression spring or an elastomer element can be connected in series with the resistance device. A spring is considered to be an elastic deformation of a solid body or a compression of a hydraulic spring or a compressible hydraulic fluid.

[0027] The energy accumulator is designed to be adjustable, with the energy accumulator or the spring being assigned an adjustment device for adjusting the spring preload or spring stiffness. This makes it possible to change the amount of energy to be stored and the manner in which the energy is released. Alternatively or additionally, a pump and / or a valve are assigned to the pressure accumulator of the energy accumulator in order to charge the pressure accumulator or to reduce pressure in order to change the pressure level. This also makes it possible to manipulate both the amount of stored energy and the manner in which it is released. In a pressure accumulator, there is a pre-pressure or there is a transmission ratio of the pressure to the force generated by the energy accumulator.

[0028] If the spring preload or spring stiffness is to be adjusted by motor, in one embodiment the adjustment device is designed as a drive, which can also generate a moment around the pivot axis. This makes it possible to avoid the need for a separate component for changing the spring preload and / or spring stiffness, but rather to use the drive as the device for adjusting the force accumulator. In this case, the actual spring stiffness or preload is not adjusted, but rather the resulting mechanical behavior of the joint is changed so that it behaves as if the spring had a different stiffness and / or preload. The overall spring stiffness of the orthopedic joint device is changed.

[0029] In one embodiment, the energy accumulator and the drive are arranged and mechanically coupled in such a way that they operate in parallel. The drive introduces a driving or braking torque about the pivot axis of the orthopedic joint device, while the energy accumulator-resistance device arrangement acting in parallel enables the torque to be modified or supported by the drive. Conversely, the drive modulates the damping torque through the resistance device or the use of the energy accumulator. In a further development, the energy accumulator and the resistance device are arranged in series, which is particularly easy and compact with a hydraulic damper using a pressure accumulator. This also allows the orthopedic joint device to oscillate unaffected by the energy accumulator when the resistance device is open.

[0030] The method for controlling an orthopedic joint device, as described above, provides for the drive to influence the resistance to be operated in parallel with the resistance device and the energy storage device. The resistance device and the energy storage device are designed as passive elements, as they do not have a motor drive. In combination with the motor drive, it is possible to expand the application of an orthopedic joint device, particularly for orthoses or prostheses, and to impart properties to the orthopedic joint device that would not be possible with the individual components. The passive elements are coupled to the electromechanical or electrohydraulic drive, so that the moments or forces applied around the pivot axis result from the forces or moments of the three components.The effect of the energy storage device parallel to the drive leads to an assistance or a modification of the torque applied by the drive and in particular supplements the drive by providing comparatively high amounts of energy in a short time. This increases the torque of the drive by the torque provided by the energy storage device when it is released. The active drive can therefore be designed so that it does not have to apply the complete torque for all applications. This means that the motor drive can be smaller or optimized for other operating ranges or speeds. The energy storage device, the resistance device and the drive can be arranged in parallel to one another; alternatively, the energy storage device and the resistance device can be arranged in series and the drive parallel to both.If the resistance device is adjustable, the energy storage device can be “deactivated” by switching the resistance device to continuity.

[0031] In one embodiment, the drive and / or the resistance device and / or the energy storage device is activated, deactivated and / or modulated on the basis of sensor data in order to be able to change the movement behavior of the upper part relative to the lower part during use.

[0032] In one embodiment, the modulation of the overall system characteristics is based on the characteristics of the resistance device and / or the energy storage device by the drive. In particular, the resistance, the resistance curve, the stiffness, the stiffness curve, the damping, and / or the damping curve is reduced or increased by the drive. At specific times or under specific conditions, or when specific limit values ​​are reached, the drive is activated, deactivated, or modulated, resulting in an increase or decrease in the torque applied by the energy storage device. This allows for quick and energy-efficient adjustments to the required behavior of the orthopedic joint device.

[0033] In a further development, the energy stored in the energy storage device is converted into electrical energy via the drive and vice versa, for example by operating an electric motor in generator mode or vice versa.

[0034] The invention provides a combination of energy storage and parallel motor drive. The resulting torque is the sum of the torques applied by the energy storage and the motor. The energy storage is not to be viewed as a pure spring, but can be embedded in a hydraulic system that enables parallel and / or serial damping behavior. In one embodiment, the hydraulic spring accumulator can be loaded only in the flexion direction and discharged in the extension direction; the oil flow in and out of the spring accumulator is throttled by a proportional valve until it is blocked. In this combination, the energy storage can be used to apply the basic characteristics and the motor to modulate them. This enables significantly more flexible control than with the energy storage alone, and can also achieve greater energy efficiency and a wider bandwidth, or a higher maximum torque, than with a motor alone.As an alternative to a parallel arrangement of the motor and energy storage device, they can also be arranged in series. In this case, the displacements, rather than the torques, add up. The motor then modulates the displacement as a function of the force.

[0035] A basic idea is the change in the force-displacement behavior of the energy storage device through the drive, in particular a parallel motor. Starting from a basic characteristic of the energy storage device, an adjustment can be made via the motor. A motor torque that is aligned in the same direction as the energy storage torque increases the resulting torque, while a motor torque opposite to it reduces the resulting torque. A constant torque applied by the motor corresponds, for example, to a preload of a spring characteristic or the displacement of a spring zero point, while a displacement-dependent motor torque corresponds to the superposition of two springs, whereby a non-linear spring characteristic can be generated, in particular by the motor. If non-conservative forces occur in the energy storage device, these can also be taken into account in the control of the motor.In addition, the torque or a parameter of a characteristic of the motor can be changed over time, thereby achieving transient behavior. For example, direction-dependent behavior, hysteresis, or decaying behavior, e.g. a continuous, temporal reduction of a torque, can be implemented. It is also possible to dynamically change the torque characteristic in real time during a movement, adapting it from one repetition of a movement to the next, e.g. based on autonomous optimization, in order to make the characteristic adjustable via software and electronic interfaces. The motor torque can be selected so that it is identical in magnitude to the torque generated by the energy storage device, or at least sufficiently similar and opposite. The resulting total torque from the motor and energy storage device is therefore zero or correspondingly low.No significant additional resistance or assistance is applied to the movement. This can be useful in individual movement phases to deactivate the active energy storage, activate it in a controlled manner, or specifically add or remove energy from the energy storage without significantly influencing the movement.

[0036] For walking on level ground, an approximately linear spring response with potentially parallel damping is advantageous during stance phase flexion and extension. However, the optimal moment characteristic varies with body weight, the individual movement pattern and needs, as well as gait parameters such as stride length or walking speed. Dynamic adjustment of spring stiffness is difficult to implement. The modulation can be adapted to the body weight and height of the user, as well as to personal preferences. Furthermore, the total moment can be adjusted from step to step or in real time to the movement, the movement progress, or even the load within a control law.For example, if the inclination of the leg tendon indicates that the stance phase is terminal, but the joint is still severely flexed or has not yet sufficiently extended from maximum stance flexion, the extension torque can be increased via the motor. Such an adjustment typically occurs continuously and not abruptly.

[0037] The moment behavior in the stance phase can be adapted to the context using the combined actuator. Different contexts such as steps, ledges, inclines, surface conditions or environments require different types of support. When walking downhill on inclines, higher extension moments are typically necessary in the stance phase than when walking on level ground. Accordingly, the incline can be determined using sensors and the total torque from the energy storage device and motor can be modulated. In particular, the motor torque can be increased with increasing downward incline within a certain incline range in order to achieve greater overall stiffness, preferably in the stance phase flexion. The extension moment in the stance phase extension can also be adjusted compared to walking on level ground.For example, the change in stiffness or moment during stance phase flexion and extension can be adjusted time-dependently or based on sensor signals during downhill walking, e.g., to achieve greater hysteresis and thus greater dissipation. Similar adjustments can also be made for other contexts. The control system provides the option of increasing or decreasing resistance during the stance phase.

[0038] With an energy storage device, energy must always be input before energy can be withdrawn, with the same or even higher forces and torques being required for charging than for discharging. In addition, charging the energy storage device may require a relative movement if it is physically coupled to the pivoting movement. For example, it is not possible or only possible with difficulty to charge the energy storage device by absorbing kinetic energy in the swing phase with a low torque and large range of movement and to release the energy in the stance phase, when a high torque and small range of movement is required. This problem can be solved using a combined actuator. For example, during the swing phase flexion, the energy storage device can be charged by a motor torque opposite to the energy storage device.If the generated moments are opposite and equal in magnitude, they cancel each other out and the movement is not influenced, or the movement is not subjected to any additional resistance by the energy storage device. With increasing flexion, the motor torque increases until the energy storage device is fully charged or no further flexion occurs. By maintaining the flexion moment of the motor or switching off the energy storage device, the release of the energy from the energy storage device can be delayed or only occur at a later time. When climbing stairs, the energy stored in the energy storage device can be released during stance phase extension. The extension moment generated by the energy storage device can be supported by a motor torque in the same direction, whereby the total extension moment can be increased.

[0039] If the energy storage device is charged and the stored energy cannot be used effectively, the energy storage device can be discharged. This typically occurs dissipatively. The discharge can generate an undesirable moment. Alternatively or additionally, the motor can be used to apply a moment that is opposite to the energy storage device and essentially equal in magnitude, so that the resulting moment is almost zero or sufficiently small. This allows the energy storage device to be discharged in such a way that it has no significant influence on the movement. It is also possible to reduce the moment of the energy storage device via the motor. For example, the energy storage device can become undesirably charged during the stance phase of flexion when walking down stairs.If the stored energy is not needed during the gait cycle of descending stairs and the energy storage device should be discharged again during the subsequent initial contact, the energy storage device must be discharged before the initial contact. This can be done, for example, during swing phase extension, whereby the extension moment of the energy storage device is counteracted by a bending moment from the motor during the discharge, which sufficiently reduces the resulting extension moment or compensates for the extension moment of the energy storage device.

[0040] A combined actuator consisting of a power storage unit and a motor can also improve energy recuperation via the motor and thus the generation of electrical energy. Operating a motor as a generator is not possible or only inefficiently possible at low speeds. However, with a combined actuator, it is possible to store energy in the power storage unit during slow movements and thus at low speeds, and later use the power storage unit at high speeds to operate the motor in generator mode for efficient energy recuperation. A further advantage is the low heat generation compared to the energy dissipation during the energy storage charging phase.

[0041] When walking downhill, for example, the energy storage unit can be charged during the stance phase flexion and later discharged during the swing phase extension, especially at high extension speeds. The extension moment of the energy storage unit is counteracted by a flexion moment via the motor. The motor is controlled in such a way that it operates as a generator, generating electrical energy. The motor and energy storage unit are preferably controlled in such a way that the motor torque and the torque generated by the energy storage unit cancel each other out, thus not significantly affecting the movement.

[0042] The motor torque can be used to obtain movement information, e.g. inclination of the lower leg, leg tendon, upper body inclination or force information, e.g. COP (Center Of Pressure), ankle torque, forces and torques in the interface to the person using the aid and the contralateral side. The control also includes variables derived from sensor data such as the thigh angle, which can be calculated from the knee angle and lower leg angle, or the lever arm as the quotient of torque and force. Human-machine interfaces or AI algorithms can also be used as additional inputs. It is also possible to use multiple variables to control the torque. The resulting total torque from the motor torque and the torque from the force storage device is therefore particularly a function of the knee angle due to the physical coupling of the knee angle and force storage device and possibly other input variables.

[0043] Method for controlling an orthopaedic joint device as described above provides that the drive for influencing the resistance is operated in parallel to the resistance device and the force storage device.

[0044] In one embodiment, the drive, the resistance device, and / or the energy storage device are activated, deactivated, and / or modulated based on sensor data, wherein the sensor data is assigned to and transmitted to a controller or control device. Alternatively or additionally, the resistance device and / or the energy storage device are activated, deactivated, and / or modulated based on sensor data. In particular, the control device is also supplied with the sensor data and is coupled to the resistance device and / or the energy storage device in order to make the corresponding changes to or in the resistance device and / or the energy storage device based on the sensor data.

[0045] The modulation of the overall characteristics of the orthopedic joint device is based on the characteristics of the resistance device, which forms the basis or basis for influencing the movement behavior of the orthopedic joint device. This basic characteristic is modulated by the drive. The basic characteristic can also be achieved by the energy storage device or a combination of energy storage device and resistance device, particularly in the form of passive components. The drive then makes the appropriate adjustments to the respective basic characteristics. In particular, a reduction or increase in the resistance, the resistance curve, the stiffness, the stiffness curve, the damping, and / or the damping curve takes place.

[0046] In a further development, the conversion of energy stored in the energy storage device into electrical energy takes place via the drive and vice versa.

[0047] The energy storage device can be decoupled from the other components, i.e. the resistance device and the drive, and kept in a charged state in order to be switched on again at a later time so that the energy stored in the energy storage device can be supplied to the system in a controlled manner.

[0048] In one embodiment, the drive is operated in such a way that the effect of the resistance device is canceled, so that a free pivoting of the upper part relative to the lower part can be adjusted.

[0049] Exemplary embodiments of the invention are explained in more detail below with reference to the accompanying figures. They show:

[0050] Figure 1 - a schematic representation of a prosthetic leg;

[0051] Figure 2 - an embodiment of a hydraulic circuit diagram;

[0052] Figure 3 - Variants with orthoses;

[0053] Figures 4 to 15 - Application examples using a prosthetic leg;

[0054] Figures 16 to 26 - different moment curves;

[0055] Figure 27 - a torque curve with several input signals;

[0056] Figures 28 - a relationship between several input variables;

[0057] Figure 29 - Representations of a variant of the joint device;

[0058] Figure 30 - a detailed view of an energy storage device; Figure 31 - a design of a progressive energy storage device; and Figure 32 - a detailed view of the energy storage device.

[0059] Figure 1 shows a schematic representation of an orthopedic joint device as part of a prosthetic leg with a femoral shaft as the upper part 10 and a lower leg part as the lower part 20. The upper part 10 and the lower part 20 are pivotally attached to one another about a pivot axis 15. A prosthetic foot is arranged on the lower leg part. Between the upper part 10 and the lower part 20 is a resistance device 30 in the form of a schematically illustrated hydraulic damper 30, which provides or can provide resistance to pivoting in both the extension direction and the flexion direction. In the illustrated embodiment, the hydraulic damper 30 is designed as a linear damper and has a housing 32 in which a cylinder 34 is formed. Within the cylinder 34, a piston 36 is arranged on a piston rod 33 and divides the cylinder 34 into two chambers.A fluidic connection is formed between the chambers, which will be explained in more detail later. The hydraulic damper 30 is mechanically coupled to the upper part 10 at its proximal end on the piston rod 33 via a first fastening point 31. The housing 32 is mechanically coupled to the lower part 20 at the distal end of the hydraulic damper 34 via a second fastening point 37. The flow resistance within the hydraulic connection between the two chambers is adjustable when the piston 36 moves within the cylinder 34 in order to dampen the movement in a way that is adapted to the respective situation. In addition, a drive 60 is arranged between the upper part 10 and the lower part 20, which drive is designed and configured to effect, assist, or hinder a pivoting of the upper part 10 relative to the lower part 20.This is achieved, for example, by the drive 60 in the form of an electric motor applying a torque to the orthopedic joint device via a gear 70 in order to move the lower part 20, for example, in the extension direction during the swing phase. All other support or influences on states or movement situations between the upper part 10 and the lower part 20 can also be influenced via the drive 60 with the motor and the gear 70. Both components of the orthopedic joint device that influence the movement, i.e. the hydraulic damper 30 and the drive 60, act simultaneously or can act simultaneously and in parallel between the upper part 10 and the lower part 20 to apply a torque about the pivot axis 15. Instead of a linear damper, the hydraulic damper can also be designed as a rotary hydraulic system.

[0060] As an alternative to the design of the orthopedic joint device as a component in a prosthetic leg, Figure 3 shows two alternative applications in which the orthopedic joint device is designed as part of an orthosis. The exemplary embodiments in Figure 3 show a first orthosis for the upper extremity in the form of an elbow orthosis and a second orthosis for the lower extremity in the form of a knee orthosis. Not all components are shown on the elbow orthosis, but all components are also present there. Each orthosis has an upper part 10 and a lower part 20, which are secured to the respective body part via fastening devices 19, 29, for example in the form of cuffs, shells, straps or similar fastening devices or combinations thereof.For the elbow orthosis, the attachment is made to the upper arm and forearm; for the knee orthosis, the attachment is made via thigh cuffs 19 and lower leg cuffs 29. The knee orthosis illustrates that the hydraulic damper 30, like the drive 60, operates around the pivot axis 15. The hydraulic damper 30 is again attached to the upper part 10 by one end of the piston rod and to the lower part 20 by the housing part. Furthermore, sensors 95 are arranged on or associated with the upper part 10 and the lower part 20, which are connected to a control device 80. The connection can be made either by wire, radio, or another type of signal transmission. The control device 80 is coupled to the drive 60 and the hydraulic damper 30 and enables activation, deactivation, or modulation of the drive 60, as well as adjustment of valves within the hydraulic damper 30.The control device 80 has all the necessary data processing devices, memory, software, hardware, interfaces, and a power supply to effect the control or regulation of both the drive 60 and the hydraulic damper 30. The drive 60 can be supplied with the necessary electrical energy via an additional energy storage device in the form of a battery or an accumulator. The drive 60 can be operated both as a motor and as a generator in order to convert the kinetic energy back into electrical energy, for example, when additional braking power is required or when the resistance to pivoting increases. The sensors 95 can be force sensors, torque sensors, position sensors, pressure sensors, temperature sensors, and IMUs. Multiple sensors can be arranged on both the upper part 10 and the lower part 20.Based on the transmitted sensor values, the corresponding switching commands are then issued by the control device 80.

[0061] In the embodiment according to Figure 1 as well as in the embodiment according to Figure 3, in addition to the resistance device 30 and the motor drive 60, an energy accumulator 90 is arranged between the upper part 10 and the lower part 20 in order to assist, hinder or effect a pivoting or pivotability of the upper part 10 relative to the lower part 20. The energy accumulator 90 in Figure 1 is, for example, arranged distally on the resistance device 30 and is effectively connected in series with the resistance device 30. The same applies to the embodiment according to Figure 3, in which the energy accumulator, for example in the form of an adjustable and lockable mechanical or pneumatic spring or an elastomer element, is arranged below the housing of the resistance device 30.

[0062] Figure 2 shows a hydraulic circuit diagram of the hydraulic damper 30, with a housing 32 that forms or accommodates a cylinder 34. The cylinder 34 is divided by the piston 36 into a first chamber 341 and a second chamber 342. A hydraulic connection 40 in the form of flow channels is arranged between the two chambers 341, 342, so that hydraulic fluid flows from the first chamber 341 into the second chamber 342 when the piston 36 is pressed downward, for example during flexion. Conversely, hydraulic fluid from the second chamber 342 is conducted through the fluid connection 40 into the first chamber 341 when an extension movement occurs.Due to the volume difference between the displacement in the first chamber 341 in relation to the second chamber 342 due to the piston rod 33 located in the second chamber 342, a compensation volume 38 is arranged in the hydraulic damper 30 or coupled thereto. Two adjustable valves 50 in the form of switching valves are arranged within the fluid connection 40. Each chamber 341, 342 is assigned a switching valve 50. A check valve 55 is arranged parallel to each switching valve 50 as a bypass in the fluid connection 40. With two check valves 55, one of which is assigned to each chamber 341, 342, the two check valves 55 are arranged to act in opposite directions.Both check valves 55 allow hydraulic fluid to flow into the respective chamber 341, 342, but block the flow in the opposite direction, so that the hydraulic fluid exiting from the chamber 341, 342 must be passed through the switching valve 50.

[0063] In the illustrated embodiment, the switching valves 50 are designed as 3-way switching valves that can be switched between three discrete states. In the illustrated switching state, the fluid connection 40 is interrupted, meaning that no hydraulic fluid can flow from one chamber 341 to the other chamber 342. The prosthetic knee joint or the orthopedic joint device is locked in this position.

[0064] A throttle 56 is arranged upstream of the respective switching valve 50 in the direction of flow from the chamber, which, for example, halves the flow cross-section or reduces it to the desired value. The throttle cross-section is preferably adjustable. A flow channel with a maximum or fully open flow cross-section is provided parallel to this throttle 56 and leads to the switching valve 50. If the switching valve 50 is moved downward from the illustrated interrupted and thus blocked position, which can be done by an electromagnet or another actuator or drive, the line not subjected to the throttle 56 is supplied with hydraulic fluid and can pass the hydraulic fluid through unhindered during an extension movement in which the piston 36 is moved upward.

[0065] If the switching valve 50 is moved upward from the illustrated locked position, hydraulic fluid from the second chamber 342 must first pass through the upstream throttle 56 and then through the check valve 55 into the first chamber 341. In this position, there is increased flow resistance, so that the pivoting movement in the extension direction is dampened. The switching valve 50 assigned to the first chamber 341 is connected accordingly for the flexion movement.

[0066] The adjustment or displacement of the switching valves 50 is carried out sensor-based via the control device 80. Based on the sensor data of the sensors 95, the respective actuator for the switching valve 50 is activated or deactivated and the corresponding switching position is assumed.

[0067] If the one-time reduction in flow cross-section provided by the throttle 56 is insufficient or too great to provide the desired or required resistance, the drive 60 is activated, so that an additional torque is applied via the motor and, if applicable, the gear box, which either counteracts or supports the movement to increase or decrease the resistance. The activation of the motor 60 is also carried out via the controller 80 based on sensor values ​​and control programs and software stored in the controller 80.

[0068] Figure 4a shows a schematic representation of an orthopedic joint device using a prosthetic leg. The upper part 10 is, for example, the femoral shaft or the upper part of a prosthetic knee joint, and the lower part 20 is the lower leg tube, which is pivotably mounted on the upper part 10 about the pivot axis 15. The resistance device 30, in the form of a hydraulic linear damper, is attached to the upper part 10 by the piston rod. The housing, in which the piston is moved downward during flexion and upward during extension, is attached to the lower part 20 with the interposition of the energy accumulator 90. The energy accumulator 90 is designed as a spring or pressure accumulator and can have an adjustment device with which the spring preload and / or spring stiffness can be adjusted.In the embodiment of the energy accumulator 90 as a pressure accumulator, a pump and a valve are assigned to the pressure accumulator in order to increase or decrease the pressure and thereby adjust the spring preload or the spring stiffness. The resistance device 30 and the energy accumulator 90 can be designed as a module and combined to form a structural unit. Also assigned to the orthopedic joint device is a motor drive 60 which is set up and designed to bring about a pivoting movement of the upper part 10 relative to the lower part 20, to counteract such a pivoting movement or to assist it. The drive 60 thus also acts as a resistance device when the drive 60 is controlled by the control device 80 (not shown) in such a way that it counteracts a pivoting movement. The drive 60 for influencing the resistance to a pivoting movement orto support a pivoting movement of the upper part 10 relative to the lower part acts parallel to the resistance device 30 and the force accumulator 90 connected in series therewith.

[0069] Figure 4b shows a device as in Figure 4a, in which the energy accumulator 90 is adjustable; a damping device or resistance device 30, which in Figure 4a is arranged in series with the energy accumulator 90, is not present in Figure 4b.

[0070] The fundamentally identical structure of Figure 4a is shown in Figure 5, with the difference that the resistance device 30 is adjustable to allow for setting the resistance to a pivoting movement. In a hydraulic damper configuration, the adjustment is achieved by changing the flow cross-section within the hydraulic lines in the resistance device 30, for example, by changing the passage cross-sections in valves or throttles. The adjustment is performed based, for example, on sensor data, adaptively during the movement or once by an orthopedic technician to adapt the resistance device 30 to the patient and the individual components of the orthopedic joint device.The adjustability also allows adaptation to changing properties of the orthopaedic joint device, wear and tear, changes in different types of use or due to changing abilities or preferences of the respective user.

[0071] In Figure 6, instead of the resistance device 30, the energy storage device 90 is adjustable, in particular adjustable and also lockable. The adjustability of the energy storage device 90 enables adjustment of the amount of energy that can be stored in the energy storage device 90 and thus also the amount of energy that can be used to support the pivoting movement or to act in the opposite direction, i.e., to hinder or prevent a pivoting movement. The adjustment of both the energy storage device 90 and, if applicable, the resistance device 30 is carried out, for example, sensor-controlled via the sensors described above and the control system, which is not shown for reasons of clarity.

[0072] In Figure 7, both the resistance device 30 and the energy accumulator 90 are adjustable, in particular adjustable and lockable.

[0073] Figure 8 shows a variant of the arrangement of resistance device 30, drive 60, and energy storage device 90, all of which are arranged on the front side of the orthopedic joint device. In the illustrated embodiment, the resistance device 30 and the energy storage device 90 are not adjustable or adjustable, but can be combined with the drive 60 as desired in order to provide the desired resistance to a pivoting movement or to support a pivoting movement accordingly. In Figures 9 and 10, the resistance device 30 and the energy storage device 90 are adjustable and used as in the arrangement according to Figure 8. In Figure 11, both the energy storage device 90 and the resistance device 30 are adjustable and adjustable.

[0074] A variant of the arrangement of resistance device 30, drive 60, and energy accumulator 90 is shown in Figure 12. The drive 60 is arranged so as to operate in parallel with the energy accumulator 90 and is connected in series with the resistance device 30. Both the resistance device 30 and the energy accumulator 90 are designed to be adjustable. In this configuration, it is possible to charge the energy accumulator 90 via the drive 60. The drive 60 then serves as the adjustment device for adjusting the spring preload or spring stiffness, or for adjusting the pressure within the pressure accumulator if such is designed as an energy accumulator 90. The energy accumulator 90 and the drive 60 are thus arranged so as to operate in parallel with one another.If, for example, the drive 60 is to be operated in generator mode, it is sensible and possible to lock the energy accumulator 90 in order to use the kinetic energy from the relative movement between the upper part 10 and the lower part 20 to move the drive 60 without any losses. For this purpose, the resistance device 30 is also designed to be lockable and is advantageously locked in generator mode. This makes it possible to convert the entire kinetic energy from the relative movement of the upper part 10 to the lower part 20 via the drive 60 into generator mode as electrical energy and to feed it to a corresponding energy store or accumulator. The movement of the upper part 10 and the lower part 20 relative to one another is influenced by all three components, namely the resistance device 30, the drive 60 and the energy accumulator 90, by assisting, hindering or preventing pivoting.

[0075] Figure 13 shows a further variant of the orthopedic joint device with an upper part 10, a lower part 20, and a joint arranged therebetween for pivoting relative to one another about a pivot axis 15, exemplary for either a prosthetic leg or a leg orthosis. A resistance device 30, for example in the form of a hydraulic or pneumatic damper, a magnetorheological resistance device, or a friction brake, is arranged parallel to an energy accumulator 90, which is designed, for example, as a compressed air accumulator, an elastomer element, or a mechanical spring. The energy accumulator 90 is adjustable and switchable. Also arranged parallel to it is a motor drive 60 in the upper part 10 and the lower part 20 in order to influence a pivoting movement in the extension direction and / or flexion direction.The motor drive 60 supports or counteracts a pivoting movement of the lower part 20 relative to the upper part 10. The energy storage device 90 is switchably coupled to the resistance device 30, so that the resistance device 30 can be operated in combination with the drive 60, in combination with the energy storage device 90, or in combination with the drive 60 and the energy storage device 90. In addition, the resistance device 30 can be used without any additional component to influence the pivoting movement. In the embodiment according to Figure 13, the drive is designed as a rotationally acting motor drive parallel to the energy storage device 90.

[0076] In Figure 14, the resistance device 30, the energy storage device 90, and the motor drive 60 are arranged parallel to one another, with the motor drive 60 being designed as a linear drive. In Figure 15, the motor drive 60 is designed as a linear drive, which is arranged in series with the other components connected in parallel, namely the energy storage device 90 and the resistance device 30.

[0077] In all embodiments of Figures 13 to 15, the illustrated energy storage device 90 can store the mechanical work performed on it as internal energy and, when energy is released, perform work on its surroundings. The energy storage devices 90 are designed, in particular, as mechanical, hydraulic, or pneumatic springs. The respective energy storage device 90 can be coupled into and out of the chain of action, for example, via a valve in a hydraulic circuit or via a mechanical coupling. This makes it possible to couple the energy storage device 90 to the upper part 10 and / or the lower part 20, or to disengage them, whereby this can occur at any knee angle or joint angle between the upper part 10 and the lower part 20.

[0078] When the motor drive 60 is arranged in series with the energy storage device 90, the moments about the pivot axis 15 do not add up. Rather, the transmitted forces or moments are identical for both components, and the lengths or displacements add up or are combined. Nevertheless, a superposition occurs, which modulates the characteristic curves, for example, the force-displacement behavior or the moment-angle behavior, so that a change in preload and stiffness, non-monotonic characteristics, transparent modes, and a transfer of energy from the drive 60 to the energy storage device 90 and vice versa can occur. Thus, a shift in the characteristic curve is modulated as a function of the moment.

[0079] In Figure 14, a positive superposition Mz of the characteristic curve MA of the drive 60 and the characteristic curve Ms of the energy storage device 90 is shown over the swivel angle <p dargestellt. Die Darstellung der positiven Überlagerung Mz bezieht sich auf das generierte Kniemoment als Funktion des Kniewinkels <p, bei der der Kraftspeicher 90 in zumindest eine Bewegungsphase klimatisch dem Kniewinkel 4 gekoppelt ist. Allgemein ist der Kniewinkel <p der aktuierte Freiheitsgrad und M das zugehörige Moment oder die dazugehörige Kraft. In dem Ausführungsbeispiel der Figur 14 ist der Kraftspeicher 90 eine progressive Feder mit einer Vorspannung. Der Antrieb 60 ist ein Motor, der entsprechend einer linearen Feder angesteuert wird, wobei das erzeugte Moment des Motors mit dem Moment des Kraftspeichers 90 gleichgerichtet ist.The torques generated by the energy storage device 90 and the drive 60 therefore add up, resulting in a characteristic curve of the positive superposition Mz with increased rigidity compared to the characteristic curve Ms of the energy storage device 90 alone. The preload in the characteristic curve Ms at an output angle cpo remains unchanged by the torque of the motor or drive 60. The drive 60 modulates the overall characteristic curve in the form of the positive superposition Mz based on the characteristic curve Ms of the energy storage device.

[0080] Figure 17 shows a representation of the lines during a weakening modulation by the drive 60. The characteristic curve MS of the energy storage device is designed according to that in Figure 16, while the characteristic curve MA of the drive is linear, as in Figure 16, but has an opposite direction of action. The drive 60 acts according to a linear characteristic curve, which at the initial angle cpo corresponds in magnitude to the stiffness of the energy storage device 90 and thus has an offset opposite to the preload of the energy storage device 90. In the range from the initial angle cpo to the limit angle <pi heben sich die Momente um die Schwenkachse 15 im Wesentlichen auf. Mit zunehmendem Gelenkwinkel nimmt das Moment des Kraftspeichers 90 durch die Progression stärker zu als jene des Antriebs 60, sodass sich eine progressive Momentzunahme bzw. Steifigkeitszunahme ergibt, was durch die Überlagerung Mz deutlich wird, die ab dem Grenzwinkel zunimmt.The resulting characteristic curve of the superposition Mz is significantly modified by the drive 60 compared to the superposition Mz in Figure 16, both in terms of the effective preload and the total torque and characteristics. By applying a drive torque that opposes the torque of the energy accumulator 60, the resulting torque about the pivot axis can be reduced as desired.

[0081] In Figure 18, the moment of the energy storage device 90 is fully compensated by the drive 60. The drive 60 applies a moment of equal magnitude but opposite direction to the moment of the energy storage device 90, so that both moments essentially cancel each other out. The superimposed moment or superposition Mz is 0 or essentially 0 over the entire angular range. Such control allows the energy storage device 90 to be charged or discharged without affecting the movement of the orthopedic device. Such complete compensation of the moment of the energy storage device by the drive is also called transparent mode.

[0082] Figure 19 shows the modulation of the resulting moment or the superposition Mz of a moment Ms of the energy storage device 90 by a moment MA of the drive 60 as a function of the direction of movement. The moment MA applied by the drive 60 is varied as a function of the direction of movement in order to achieve a direction-dependent characteristic curve of the superposition Mz or the resulting moment. In Figure 19, the moment Ms of the energy storage device 90 is amplified by the drive torque MA during flexion and weakened during extension, with the initial angle cpo representing the fully extended position of the joint. Overall, this leads to a hysteresis of the superposition Mz.

[0083] Figure 20 shows that the moment MA applied by the drive 60 is varied depending on the effective direction of the force accumulator 90. Amplification occurs in the flexion direction, starting from a zero point at the intersection point of the coordinate axes; in the extension direction, attenuation occurs due to the moment MA of the drive 60. The changes or modulations described above can be combined with one another; instead of a zero crossing of the speed or a zero point, exceeding or falling below a threshold value can also be used to change the characteristic curve of the moment MA by the drive 60.

[0084] Figure 21 shows a non-monotonic combination of an amplification or attenuation of a moment Ms applied by the force accumulator 90 by a moment MA of the drive 60. At the initial angle, the drive 60 applies a moment opposite to the moment due to the preload of the force accumulator 90, so that the total moment is zero. Between the initial angle and the limit angle, the drive 60 is operated according to a linear spring stiffness, with the increase in the joint angle <p das Vorzeichen des Momentes MA von dem Antrieb 60 ändert, von einem entgegenwirkenden zu einem unterstützenden Moment. Dies geschieht ungefähr in der Mitte zwischen dem Ausgangswinkel cpo und dem Grenzwinkel epi .From the critical angle <pi wird das von dem Antrieb 60 aufgebrachte Moment MA verringert und wirkt kurz nach dem Grenzwinkel <pi dem Moment MA des Kraftspeichers 90 entgegen, wobei ab dem Grenzwinkel <pi fließend zu einer negativen Federsteifigkeit für die Ansteuerung des Antriebs 60 gewechselt wird. Bei einem weiter zunehmenden Gelenkwinkel cp wirkt das Moment MA des Antriebes 60 dem Moment Ms des Kraftspeichers 90 entgegen. Die resultierende Momentenkennlinie Mz als Überlagerung von Motormoment MA und Kraftspeichermoment MA startet zunächst momentenfrei bei dem Ausgangswinkel cpo, nimmt zwischen dem Ausgangswinkel cpo und dem Grenzwinkel <pi zu und wird ab dem Grenzwinkel <pi bei zunehmendem Gelenkwinkel cp wieder abgeschwächt.

[0085] In Figure 22, a combination of moments of the drive 60 and the energy storage 90 is realized in such a way that from an initial angle cpo to a limit angle <pi einem Moment Ms von dem Kraftspeicher 90 zunächst ein dem Kraftspeichermoment Ms entgegenwirkendes Moment MA des Antriebes 60 aufgebracht wird, sodass sich die Überlagerung Mz zu im Wesentlichen 0 ergibt, sodass keine Beeinflussung der orthopädietechnischen Gelenkeinrichtung hinsichtlich der Verschwenkbarkeit ergibt. Ab dem Grenzwinkel <pi wird der Antrieb 60 so angesteuert, dass das durch den Antrieb 60 aufgebrachte Moment MA betragsmäßig reduziert wird und im weiteren Verlauf von einem sich entgegenwirkenden Moment zu einem unterstützenden Moment wird, sodass das Moment MA des Antriebes und das Moment Ms des Kraftspeichers 90 in die gleiche Richtung wirken.The modulation of the characteristic curve of the moment Ms of the energy accumulator 90 by the drive 60 results in the characteristic curve of the superposition Mz of a one-sided, progressive spring. Only when the limit angle is exceeded <pi ergibt sich ein Gesamtmoment oder eine Überlagerung Mz, die die Verschwenkbewegung beeinflusst.

[0086] Figures 23 and 24 show various characteristic curves and angle profiles over time that occur for charging the force storage device 90 or an energy storage device during flexion of the joint, for example, during knee flexion. The designations of the moments correspond to the designations of the aforementioned figures, the angle <px ist der Kniewinkel. Die Momente, die auf den Antrieb in Gestalt eines elektrischen Motors und den Kraftspeicher wirken, werden mit MA und Ms bezeichnet. Die Momente an den jeweiligen Befestigungsstellen der Komponenten dem Oberteil bzw. Unterteil wirken entsprechend entgegengesetzt. Wird der mit dem Kniewinkel <PK gekoppelte Kraftspeicher geladen, wird normalerweise der Bewegung oder der Kniebeugung ein Moment entgegengesetzt, da an dem Kraftspeicher Arbeit verrichtet werden muss.In combination with a motor, the work to be performed can be carried out by the motor, so that the pivoting movement of the upper part relative to the lower part is not influenced. The energy stored in the energy storage device can then be released again at a later time. If the energy storage device and the motor act in the same direction during energy release, the total moment Mz can be significantly increased. In Figure 23, the energy storage device is first charged by the motor. At the beginning of the flexion movement, the energy storage device is independent of the knee angle. <PK entkoppelt, sodass durch den Kraftspeicher kein Moment generiert wird. In der Flexionsphase wird zunächst ein unterstützendes, in diesem Fall ein mit dem Kniewinkel zunehmendes Moment durch den Motor aufgebracht, um die Beugebewegung zu erleichtern. Ab dem Zeitpunkt ti wird der Kraftspeicher zugeschaltet.Further knee flexion with an increase in knee angle <px resultiert in einem Kraftanstieg in dem Kraftspeicher entsprechend seiner Kennlinie. Das Motormoment wird entsprechend so angepasst, dass das Moment des Kraftspeichers kompensiert wird. Das resultierende Moment als Überlagerung von dem Motormoment und dem Kraftspeichermoment entspricht dann dem gewünschten Verlauf für die Unterstützung der Beugebewegung. Die von dem Motor verrichtete Arbeit ist dabei größer als die an dem Kraftspeicher verrichtete Arbeit, wodurch der Verschwenkung des Oberteils relativ zu dem Unterteil kein Bewegungswiderstand entgegengebracht wird, sondern positive Arbeit verrichtet wird. Alternativ kann die Bewegung in der Beugung nicht unterstützt werden, beispielsweise würde das Motormoment so gewählt, dass sich die Momente von dem Motor und Kraftspeicher gegenseitig aufheben oder dass das Moment des Kraftspeichers hinreichend abgeschwächt wird.After charging the energy storage device, the energy storage device is decoupled from the orthopaedic joint device and is independent of the joint angle cpK, so that the energy stored in the energy storage device is retained.

[0087] Figure 24 shows the energy storage device discharging. During discharging, the energy storage device generates an extension moment between the upper and lower sections and performs work. To increase the extension moment, the motor can apply an additional extension moment or stretching moment, so that the total moment Mz is higher than that of the energy storage device. With extension, i.e. a decreasing knee angle q>K, the motor torque is reduced in the variant shown here. The moment Ms due to the energy storage device also reduces in line with the characteristic curve of the energy storage device, resulting in the decreasing torque curve shown. The energy storage device is completely discharged before the knee joint has fully extended. Decoupling and coupling the energy storage device enables the energy storage device to charge and discharge in different knee angle ranges.

[0088] The phases shown in Figures 23 and 24 can also be used independently of each other, whereby charging requires an energy storage device that is not fully charged and discharging requires an energy storage device that is not fully discharged.

[0089] Figure 25 shows the loading of the energy storage device during a flexion movement on an artificial knee joint. Initially, only the moment Ms of the energy storage device acts, and the knee moment increases with increasing knee flexion. From time t1 onwards, the total moment MS is limited by an opposing moment MA of the motor, whereby the energy storage device continues to be charged. Alternatively, the energy storage device can be loaded without using the motor, although this would result in a further increase in torque. A fully or partially charged energy storage device can be decoupled from the joint so that no change occurs in the energy storage device regardless of the knee angle. The energy storage device can be recoupled at any time to either charge the energy storage device or discharge it to support a movement.

[0090] Figure 26 shows the discharging of the energy storage device during a stretching movement. While the energy storage device is performing work, work is simultaneously being performed on the motor. This is achieved by operating the motor in generator mode. In generator mode, the work performed by the energy storage device can be converted into electrical energy and stored in an accumulator. This is particularly advantageous when the energy stored in the energy storage device is not needed to support the movement. In the embodiment shown in Figure 26, the motor is operated such that the moment generated by the motor is essentially the same magnitude as the moment of the energy storage device, but acts in the opposite direction, whereby the two moments cancel each other out. As a result, the movement of the orthopedic joint device is not affected while the energy storage device is discharging.Instead of full compensation, the torque of the energy storage device can also be weakened or overcompensated. In principle, it is not necessary for the electrical energy generated by the motor during braking to be stored and used to charge a battery. The energy can also be converted into heat via resistors. It is also possible for electrical energy to be used for the braking operation of the motor. In this case, the torque of the motor serves primarily to sufficiently weaken the stretching torque when discharging the energy storage device in order to achieve a controlled discharge of the energy storage device. Discharging the energy storage device in this way can be necessary if the stored energy is not needed and the energy storage device must be partially or completely discharged for a subsequent movement phase.

[0091] Recovering energy via a generator is particularly efficient at high generator speeds. It is therefore intended to recover electrical energy during phases when the generator speed or the motor speed in generator mode is as high as possible; these can be phases with high knee angle speeds. In a design with a variable gear ratio, phases with a high gear ratio can also be used. The discharging of the energy storage device using recuperation can be delayed, so that correspondingly high engine speeds are present during recuperation by the motor. In particular, charging the energy storage device in the stance phase and discharging and recuperating in the swing phase are advantageous. The controls shown can also be used independently of one another or in combination for discharging and recuperation according to Figures 25 and 26.

[0092] In particular, it is possible to effect an energy exchange between the drive 60 and the energy storage device 90 in the energy storage device, wherein in particular the energy storage device 90 is charged via the drive 60 or the electrical energy generated during recuperation is stored in the energy storage device until it is needed.

[0093] Figure 27 shows the change in the torque curve based on additional input variables. The generation of a torque via a motor drive makes it possible to vary the torque not only with the coupled degrees of freedom of the joint, but also to alternatively or additionally use another or further input signal or several other or further input signals for modulation. In particular, sensor values ​​can be used to modulate the torque. For example, the absolute angle of the upper and / or lower parts and / or load variables such as forces, moments, and lever arms can be used as additional input variables. Signals from a human-machine interface or artificial intelligence can also be used.In Figure 27, the moment characteristic curve Mz is shown as a superposition of a parallel arranged force storage device with the moment MS and the motor drive with the moment MA in one movement phase. The characteristic curve Mz depends on both the actuated degree of freedom, in the example shown the knee angle <p, als auch von einem zusätzlichen Signal X ab, zum Beispiel dem Absolutwinkel des Unterteils. Während in dem dargestellten Ausführungsbeispiel das von dem Kraftspeicher generierte Moment Ms nur von dem Gelenkwinkel <p abhängt, kann das Motormoment MA sowohl mit dem Gelenkwinkel <p als auch mit dem Absolutwinkel X variiert werden. Dargestellt in der Figur 27 ist eine Veränderung der Steifigkeit in der M- <p -Ebene mit dem zusätzlichen Eingangssignal X, also dem Absolutwinkel.At Xo, the torque Ms of the energy storage device is amplified by the motor with the motor torque MA (MA, XO), resulting in the characteristic curve Mz, Xo, while at an absolute angle Xi, the total torque (Mz, Xi) is weakened by the motor torque MA at the angular position Xi. The characteristic curve can be continuously adjusted between the two values ​​of X; in the illustrated embodiment, the adjustment is linear. The dependence of the motor torque MA on the input variable X can take on any desired continuous or discontinuous form; it is also possible for the motor torque MA to depend only on the input variable X. Figure 28 shows the relationship between the input variables absolute angle X, joint angle ω, the torques MA from the drive and MS from the energy storage device, as well as the total torque for the characteristic curve shown in Figure 27.

[0094] Figure 29 shows two representations of a further embodiment of the orthopedic joint device. The orthopedic joint device has an upper part 10 and a lower part 20, with the lower part 20 only partially shown. Lateral structural elements designed to accommodate pins or axle elements are missing, so that the upper part 10 can be pivoted about the pivot axis 15 relative to the lower part 20. A rotary hydraulic system acts as a resistance device 30 and is assigned to the upper part 10. A hydraulic chamber is arranged within the rotary hydraulic system 30, in which a pivoting piston is mounted. The hydraulic chamber is coupled, for example, to the lower part 20, while the pivoting piston is coupled to the upper part 10, so that when the upper part 10 is pivoted relative to the lower part 20, the piston is moved within the hydraulic chamber.The dummy piston can, for example, be formed on a pivot axis that coincides with the journals or axle elements. The pivot piston divides the chamber into an extension chamber and a flexion chamber, and hydraulic fluid is moved from one chamber to the other during pivoting.

[0095] Of course, the pivoting piston can also be rotationally fixedly coupled to the lower part 20, while the housing is rotationally fixedly coupled to the upper part 10. In the illustrated embodiment, a valve unit is assigned to the rotary hydraulics 30, in which valves 50 are arranged that influence the flow behavior of the fluid from one chamber to the other. In addition to a control valve, a check valve or several control valves or check valves can be present. The rotary hydraulics as a resistance device 30 can be controlled via servo valves in order to enable precise control of the resistance device 30. An energy accumulator can be arranged within the hydraulics, for example a spring, which can be controlled via another valve.As an alternative to a hydraulic damper device, a magnetorheological hydraulic brake can also be used as a rotationally acting resistance device 30 or a friction-based brake. Arranged within the lower part 20 is a drive 60 in the form of an electric motor, which is coupled to the upper part 10 via a gear device 70. The gear device 70 has a power transmission device, for example in the form of a toothed belt, a V-belt, a chain or a rope, or gears, in order to be able to transmit forces from the drive 60 to the upper part 10. A transmission ratio can be achieved via the gear device 70, whereby the drive torque of the drive 60 can be adapted to the respective requirements. For example, the drive torque can be increased so that small drives 30 with a high speed can be used to generate a high drive torque.The transmission device 70 is shown schematically; the drive wheels or drive pulleys for transmitting forces and moments as well as the belts, chains, gears or the like are not shown for reasons of clarity.

[0096] The active drive 60, which is present in addition to the resistance device 30, not only supplies energy to provide additional, active functionality for the user, but can also compensate for existing design disadvantages of the resistance device 30. For example, the basic friction within the resistance device 30 can be eliminated or overcompensated. This allows for very good internal sealing of the pivoting piston in the rotary hydraulics through an additional sealing lip to increase the maximum braking torque of the resistance device 30 in the form of a rotary hydraulics. The additional sealing lip within the rotary hydraulics without the active drive 60 would make the orthopedic joint device difficult to pivot due to the high basic resistance, which would limit its suitability for everyday use.By compensating the second sealing lip by the drive 60, lower tolerance requirements can be placed on the remaining components without compromising functionality, thus saving manufacturing costs.

[0097] With the illustrated concept of the resistance device 30 in the area of ​​the upper part 10 or the joint head and the arrangement of the drive 60 at a distal distance therefrom, the installation space in the joint device can be better utilized. Additional installation space is available between the drive 60 and the resistance device 30 to accommodate energy storage devices or the like. The electronic control device can also be accommodated there. The gear device 70 enables a largely independent positioning of the drive 60 from the joint head, thus reducing manufacturing complexity. The knee joint axis can be continuous, for example, coinciding with the axis on which the pivoting piston is arranged or formed, resulting in greater structural stability.

[0098] Figure 30 shows an embodiment of a force accumulator 90 with which progressive spring deflection behavior can be provided. The force accumulator 90 is formed from several modules 90 A, 90 B, the two lateral modules 90 A surround a central module 90 B. In one embodiment, the modules 90 A, 90 B are made from a polyester-based polyurethane elastomer. The modules 90 A, 90 B have different lengths, the outer modules 90 A are longer than the central module 90 B. In a cylindrical embodiment of the modules 90 A, 90 B, the outer module 90 A is formed with an annular cross-section, and the central module 90 B has a preferably cylindrical cross-section that corresponds to the cavity or cylindrical free space within the module 60 A and at least partially fills it.Here, too, different lengths are available, so that the outer module 90 A is initially compressed when a force is applied in the axial direction, and when the top of the inner module 90 B is reached, increased resistance is provided due to the compression of the inner module 90 B. This leads to a jump in the resistance behavior of the orthopedic joint device. Depending on the design of the modules, the increase in compression resistance will be greater or smaller when the inner module 90 B is compressed. By adapting the material or the dimensions of the modules 90 A, 90 B, the spring characteristics as well as the force storage capacities are adjusted.

[0099] In addition to progressive spring behavior, force accumulators 90 made of elastomer material are suitable for achieving linear or, with appropriate shaping and high deformation, degressive spring behavior. Force accumulators 90 as elastomer modules are characterized by high overload resistance, so that in many applications, a travel limiter or end stop to protect the force accumulator can be omitted. An elastomer material can also be used as an end stop for the articulated device. Particularly when used in the area of ​​an end stop for an articulated device, progressive spring behavior can be advantageous to avoid discontinuities in the force curve. This prevents sudden force or torque changes and reduces mechanical loads. Furthermore, it reduces the controllability of the system and reduces noise.

[0100] In one embodiment, progressive spring behavior can be achieved by deliberately limiting the deformation of the force accumulator in the form of an elastomer module, for example, by means of a surrounding limiting structure. If a cylindrical elastomer module is arranged in a cylindrical bore with a larger inner diameter than the outer diameter of the undeformed elastomer module, the natural bulging of the elastomer module is limited after the gap or free space has been overcome. The material of the elastomer module is thereby forced into a different shape, namely the shape of the outer limit, which influences the internal, local deformation state in the elastomer material. This results in a stiffening of the elastomer module.In addition to an external sleeve with an interior shape corresponding to the outer contour of the elastomer element, this principle of deformation limitation can also apply to any non-cylindrical outer contour and / or inner contour. Targeted deviations between the outer contour of the elastomer module and the limiting structure can influence, and in particular, mitigate, the progression behavior.

[0101] Figure 31 shows a schematic representation of a force storage element 90 in the form of an elastomer module within a hydraulic system. The hydraulic system can be part of a passive resistance device 30. A cylinder 34, in which the elastomer module 90 is arranged, is formed within a housing 32. A valve can be arranged upstream of the cylinder 34 and the elastomer module 90. The elastomer module 90 is supported on a carrier, so that when pressure is applied with the hydraulic fluid, the elastomer element 90 is compressed and pressed against the inside of the cylinder 34. This increases the sealing effect of the elastomer element, possibly until the hydraulic fluid cannot escape from the additional oil chamber 34. This further enhances the progression effect.To avoid excessive progression and, if necessary, maintain a minimum hydraulic flow, overflow channels for the hydraulic fluid can be formed on the lateral circumference and / or within the elastomer module in the form of one or more bores. Figure 32 shows an embodiment of such an elastomer module as a force storage element 90. The force storage element 90 is designed as a substantially cylindrical elastomer module and has three overflow channels 690 for the hydraulic fluid on the outer circumference.

[0102] Energy storage element 90, especially in combination with a hydraulic system controlled by valves, can be used in both linear hydraulics and rotary hydraulics.

Claims

Patent claims 1. An orthopaedic joint device having an upper part (10) and a lower part (20) which are mounted on one another so as to be pivotable relative to one another about a pivot axis (15), and at least one resistance device (30) which is arranged between the upper part (10) and the lower part (20), the resistance device (30) is designed to influence a pivoting or pivotability of the upper part (10) relative to the lower part (20), characterized in that a motor drive (60) and at least one energy accumulator (90) are arranged between the upper part (10) and the lower part (20), which are designed and configured to effect, assist or hinder a pivoting or pivotability of the upper part (10) relative to the lower part (20).

2. Orthopaedic joint device according to claim 1, characterized in that the resistance device (30) and / or the energy accumulator (90) are adjustable and / or decoupleable.

3. Orthopaedic joint device according to claim 1 or 2, characterized in that the resistance device (30) has a housing (32) with a cylinder (34) in which a piston (36) is displaceably mounted and divides the cylinder (34) into two chambers (341, 342), between which at least one fluidic connection (40) is formed, in which at least one adjustable valve (50) is arranged, in particular a multi-way valve with a closed switching position, an open switching position and at least one partially open switching position.

4. Orthopaedic joint device according to one of the preceding claims, characterized in that the resistance device (30) is designed as a linear damper or rotational damper.

5. Orthopaedic joint device according to one of the preceding claims, characterized in that the drive (60) is designed as an electric motor and is coupled to the upper part (10) and the lower part (20) via a gear (70).

6. Orthopaedic joint device according to one of the preceding claims, characterized in that the resistance device (30) and / or the energy accumulator (90) and / or the drive (60) is assigned a controller (80) which is coupled to at least one sensor (95) and is configured to activate, deactivate and / or modulate the resistance device (30) and / or the energy accumulator (90) and / or the drive (60) on the basis of the sensor values.

7. Orthopaedic joint device according to one of the preceding claims, characterized in that the force accumulator (90) is designed as a spring or pressure accumulator.

8. Orthopaedic joint device according to claim 7, characterized in that the spring is assigned an adjusting device for adjusting the spring preload and / or spring stiffness.

9. Orthopaedic joint device according to claim 7, characterized in that a pump and / or a valve are assigned to the pressure accumulator as an adjusting device.

10. Orthopaedic joint device according to claim 8 or 9, characterized in that the adjusting device is the drive (60).

11. Orthopaedic joint device according to one of the preceding claims, characterized in that the energy accumulator (90) and the drive (60) are arranged to operate in parallel to one another.

12. Orthopaedic joint device according to one of the preceding claims, characterized in that the force accumulator (90) and the resistance device (30) are connected in series.

13. Method for controlling an orthopaedic joint device according to one of the preceding claims, characterized in that the drive (60) for influencing the resistance is operated in parallel with the resistance device (60) and the energy accumulator (90).

14. The method according to claim 13, characterized in that the drive (60) and / or the energy storage device (90) and / or the resistance device (30) is activated, deactivated and / or modulated on the basis of sensor data.

15. Method according to claim 13 or 14, characterized in that the modulation of the overall characteristic is carried out by the drive (60) based on the characteristic of the resistance device (30) and / or energy accumulator (90).

16. Method according to one of claims 13 to 15, characterized in that a conversion of energy stored in the energy accumulator (90) into electrical energy takes place via the drive (60) and vice versa.

17. Method according to one of claims 13 to 15, characterized in that the energy accumulator (90) is decoupled and kept in a charged state.

18. Method according to one of claims 13 to 17, characterized in that the drive (60) is operated in such a way that the effect of the resistance device (30) is canceled.

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