Method for controlling an orthopedic joint device

Abstract

The invention describes a method for controlling an orthopedic joint device of a lower extremity, having an upper part (10) and a lower part (20), which are pivotally mounted on one another in an articulated manner about a pivot axis (15), using an actuator (30), the actuator (30) is coupled to the upper part (10) and the lower part (20) and influences the motion state of the upper part (10) and / or the lower part (20), the actuator (30) is coupled to a control device (40), and the control device is coupled to at least one sensor (50) and activates, deactivates or modulates the actuator (30) based on the sensor value of the at least one sensor (50). Wherein at least one movement speed of at least one part of the orthopedic joint device is determined from the sensor values, and the actuator (30) is activated, deactivated or modulated on the basis of the movement speed in the standing phase, the movement speed and the resistance in the standing phase being inversely correlated at least for a part of the movement.

Description

TECHNICAL FIELD

[0001] The invention relates to a method for controlling an orthopedic joint device for a lower extremity, the device having an upper part and a lower part, which are pivotably mounted on each other in an articulated manner about a pivot axis, using an actuator, which is coupled to the upper part and the lower part and influences the movement state of the upper part and / or the lower part, wherein the actuator is coupled to a control device, which is coupled to at least one sensor and activates, deactivates or modulates the actuator on the basis of a sensor value from the at least one sensor, wherein at least one movement speed of at least one part of the orthopedic joint device is determined from the sensor value and the actuator is activated, deactivated or modulated on the basis of the movement speed in a stance phase. BACKGROUND

[0002] Orthopedic joint devices, in particular orthoses, exoskeletons or prostheses, have an upper part and a lower part articulated thereto. For orthoses and exoskeletons, the upper part and the lower part are fixed to a still present limb by means of a housing, a strap, a belt, a sleeve or other fixation means. By means of orthoses and exoskeletons, movements can be guided, pivoting about a joint axis can be limited, pivoting movements can be prevented or a relative alignment between limbs can be supported or determined. For polycentric joints, the pivot axis is a momentary center of rotation, which moves depending on the pivoting movement. Furthermore, orthoses can be equipped with a damping device to dampen the pivoting movement about the joint axis. The damping device can be equipped with a control system, so that a varying damping in the flexion direction and / or in the extension direction is provided depending on sensor data.

[0003] It is also known to assign a force store to the upper part or the lower part, so that a movement support can be provided from the force store by releasing the stored energy.

[0004] Prostheses replace a non-existent or no longer existing limb and serve to provide a function as close as possible to the function of a natural limb. Furthermore, prostheses aim to provide a prosthetic user with an appearance as natural as possible. A prosthesis upper part is formed, for example, as a prosthesis socket or a component fixed to a prosthesis socket, wherein the prosthesis socket serves to be fixed to a limb or a limb stump. A prosthesis joint, for example a prosthesis knee joint or a prosthesis ankle joint, connects the upper part with a lower part, which in turn can have further prosthesis components, for example a lower leg tube or a prosthetic foot.

[0005] In particular in orthoses, exoskeletons and prostheses of the lower limbs, but also in orthoses of the upper limbs, dampers, in particular hydraulic dampers or other resistance means, are arranged between the upper part and the lower part, which provide different resistances in different states or movement situations on the basis of sensor data. Such resistance means are usually formed as linear actuators, which provide a defined resistance against a flexion movement and / or an extension movement. The resistance is varied, for example, by changing the position of a valve. When the flow cross section is reduced, the corresponding movement resistance increases. Passive dampers, in particular passive hydraulic dampers, of prostheses or orthoses are purely dissipative. Here, the movement of the upper part relative to the lower part is extracted energy, where very high torques or forces can be generated. At the same time, in the open state, for example when no valve is closed or a flow restrictor is activated, the passive damping only provides a very small resistance. The working range of such orthoses or prostheses is limited, as energy cannot be input into the movement to support the movement or actively resist the movement or change from a static state.

[0006] Furthermore, orthoses, exoskeletons and prostheses with motor drives, so-called active orthoses or prostheses, are known from the prior art, in which movements are initiated, supported or braked by activating, deactivating or modulating the drive. For this purpose, stored electrical energy is converted in the actuator from a battery or accumulator. The motor drive is also used to influence the movement behavior between the orthosis or prosthesis components, for example to brake a pivoting movement. The motor drive can thus be operated in a braking operation or within the framework of a generator circuit.

[0007] Purely passive means such as dampers, as well as semi-active means such as force stores, as well as motor drives, all influence the movement behavior of the upper part and / or the lower part and are actuators that influence the movement state of the upper part and / or the lower part. An actuator can cause a movement, reverse a movement, support a movement or exert a resistance to a movement. There is also an influence on the movement state of the upper part and / or the lower part when resisting a load, maintaining a static state or preventing or resisting a change in the movement state due to external forces. This can occur, for example, when a uniform pivoting movement should continue to be maintained and external forces act in the movement direction or counter to the movement direction.

[0008] From EP 2 869 792 B1 a method for controlling an orthotic joint device for a lower limb is known, which has an upper part and a lower part hinged thereto, between which an energy conversion and / or storage device is arranged, by which kinetic energy from the relative movement between the upper part and the lower part is converted and / or stored during walking. The energy can be fed back to the joint to support the relative movement, wherein the kinetic energy is converted and / or stored in a movement cycle of the joint device and is controlled and fed back as kinetic energy in a time-delayed manner in the same movement cycle. The energy conversion rate and / or storage rate of the energy conversion and / or storage device is inversely proportional to the pivoting speed of the lower leg.

[0009] WO 2016 / 169850 A1 relates to a method for controlling the damping variation of an artificial joint of an orthosis, exoskeleton or lower limb prosthesis, the joint having a resistance unit between an upper part and a lower part pivotably connected to each other. By means of the resistance unit, the resistance is changed when a sensor signal activates a control unit associated with a regulating device. The resistance varies depending on the position and / or length of the leg tendon and its time derivative.

[0010] WO 2016 / 169848 A1 likewise relates to a method for controlling the damping variation of an artificial knee joint, wherein the flexion resistance is reduced in the swing phase. During walking or standing, a curve of at least one load characteristic acting on an orthosis or prosthesis in which the artificial knee joint is arranged is detected. If a maximum of the load characteristic curve is detected in the stance phase or during standing, and subsequently a threshold value of the load characteristic below the maximum is detected, the flexion damping is reduced to the swing phase damping level during the stance phase.

[0011] For example, in a lower limb orthotic technical device, for a microprocessor-controlled knee joint, a controlled flexion is achieved in the stance phase with a movement resistance in the flexion direction to achieve a controlled flexion in different movement situations. Depending on the respective movement situation, for example walking on a level with a stance phase flexion, going up or down a ramp or going up or down stairs, the resistance level or the resistance curve is changed.

[0012] For the stance phase flexion, a higher resistance than the standing resistance is usually generated. If the orthotic technical device is in a stationary state for a certain time, for example when the user is standing for a long time, the joint is locked and the lock is again released when moving. SUMMARY

[0013] It is the task of the present invention to provide a method for controlling a lower limb orthotic technical joint device which enables the user to use the orthotic technical device comfortably and safely with as little physical effort as possible.

[0014] This task is solved by the method having the features of the main claim. Advantageous designs and extensions of the invention are disclosed in the dependent claims, the description and the figures.

[0015] In a method for controlling a joint device of a lower extremity orthotic technology, the orthotic technology joint device has an upper part and a lower part which are pivotably mounted on each other in a hinged manner about a pivot axis, using an actuator which is coupled to the upper part and the lower part and influences the movement state of the upper part and / or the lower part, wherein the actuator is coupled to a control device which is coupled to at least one sensor and activates, deactivates or modulates the actuator on the basis of a sensor value of the at least one sensor, wherein at least one movement speed of at least one part of the orthotic technology joint device is determined from the sensor value, and the actuator is activated, deactivated or modulated on the basis of the movement speed in a stance phase, the movement speed in the stance phase and the resistance being at least for a part of the movement anti-correlated to each other, for example the resistance decreasing when the movement speed in the stance phase increases. Thus, the resistance of the relative movement of the upper part and the lower part about the pivot axis is adjusted depending on the movement speed, wherein at reduced movement speeds a reduced resistance is provided in the stance phase. In particular, the speed is considered as the movement speed, but also the translational or rotational speed of the upper part and / or the lower part can be used to determine the movement speed. The speed can also be determined by the time change of a force, a moment, a lever arm and / or a force point of action, for example by the rate of change of the force point of action moving from the ball of the foot to the heel or vice versa or by the rate of change of the ankle moment. The resistance can be a flexion resistance as well as an extension resistance. The resistance can be a passive resistance, like a resistance provided by a passive damping device, a locking device or a brake, or a force exerted by the actuator, for example a drive or a force store, which is opposite to the movement. The moment or force exerted by the actuator can resist the movement in one movement direction and influence the movement as a resistance and actively support the movement and do work in the opposite movement direction. For example, the force can resist the knee flexion and represent a flexion resistance and actively support the knee extension and act as a drive or support.

[0016] In an extension of the method, the resistance increases when the movement speed in the stance phase decreases, so that the flexion resistance in the stance phase increases when the walking speed decreases. The slower the walking speed, the longer the stance phase lasts and the smaller the step length. Therefore, it is advantageous to increase the resistance to the movement, in particular to the knee flexion, so that the sinking proceeds slowly and the user does not have to lift his center of gravity excessively at the end of the stance phase flexion to complete the gait. By increasing the resistance with decreasing speed, the movement range, for example the range of knee flexion, can be reduced or the movement can be completely blocked and / or the movement range can be increased or the movement can be allowed with increasing speed.

[0017] In one design of the method, the change in resistance starts only from a prescribed threshold and / or only reaches a prescribed threshold of movement velocity. The movement velocity is in particular the walking velocity, wherein in addition to the forward velocity, also sideways or backward velocity can be employed. Alternatively, the velocity is a rotational movement about an axis. Preferably, the movement velocity is determined in the respective stance phase itself, the determination being as real-time as possible, and only the velocity in the previous step or movement phase is taken as a boundary condition, since the movement velocity can change at any time, and the change in resistance is preferably adapted to the current conditions, rather than to the gait or movement at a previous point in time. The change in resistance starts only from a prescribed threshold of the change in movement velocity, resulting in changes at very small and / or large velocities not being considered, and the control effort as well as the energy consumption being reduced. Alternatively or additionally, the change in resistance starts only from and / or reaches a prescribed threshold of the change in velocity, so that smaller changes in velocity are not considered and likewise the control effort and energy consumption are reduced.

[0018] In one design of the method, the resistance changes non-linearly in at least one velocity range, in particular the resistance is initially almost constant at low velocities and only slightly decreases at a small increase in velocity, and decreases with increasing velocity, wherein in particular a saturation occurs at very high movement velocities, and the flexion or extension resistance approaches a limit value. Alternatively or additionally, the resistance decreases in at least one velocity range in proportion to a power of the movement velocity, in particular the square of the movement velocity. The decrease in resistance with increasing velocity can also be designed as a one- or multi-stage discrete phase or level.

[0019] The change in resistance can be achieved by changing the resistance level, i.e. uniformly increasing the resistance, for example over the entire pivot range. The resistance level or the resistance curve can vary with the pivot range, for example setting the resistance to adapt to the load as a function of the angular position. The change in resistance can also be made by changing the resistance curve, for example starting from a standard resistance curve for a specific movement velocity, increasing the resistance over partial areas as a function of the pivot angle or as a function of the movement duration at a decrease in velocity, and intensifying the decrease at an increase in movement velocity.

[0020] The change of resistance can additionally depend on forces, relative and / or absolute angles, and / or moments, positions of components or limbs relative to each other or to the environment, and / or their time curves and time derivatives, which are determined by sensors or calculated from sensors. These quantities can relate to the supported side or the side being cared for, but also to the opposite side. The change of resistance can also directly depend on time. Thus, the adjustment of the resistance can also be based on other determined quantities, such as knee angle, segment angle, leg tendon angle, ground reaction force vector, moment, force, lever arm, quantities of the opposite side, or a combination of one or more of these quantities or factors. Time derivatives can also be used to adjust the resistance. Properties of the environment, such as the inclination, geometry or properties of the ground, can also be determined from sensor data and used to adjust the resistance. In this case, the relationship between the quantity or factor and the resistance can additionally depend on the speed of movement and change with the speed. For example, at low speeds, at relatively small knee angles, the resistance can be increased more strongly or earlier than at higher speeds or at larger knee angles.

[0021] In one design, the resistance curve and / or the resistance level is changed individually for each stance phase, thus providing the correct resistance level or resistance curve for each current stance phase.

[0022] An extension provides that the speed of movement, in particular the walking speed of a lower limb orthotic device, in particular with a prosthetic knee joint, is calculated or determined by the determined position and / or length of the leg tendon and / or its rate of change and is the basis for the change of resistance. The leg tendon is in particular the connecting line between the hip rotation point and the foot point, in particular defined at the end of the extension of the lower leg portion to the sole area. The foot point can also be defined as the rotation point of the foot relative to the lower leg or the roll point or instantaneous center of rotation of the foot. Thus, the length of the leg tendon changes by the change of the knee angle, and the position and orientation of the leg tendon change by the pivoting around the foot point in the stance phase or around the hip rotation point in the swing phase. Either the leg tendon of the supported side or the leg tendon of the opposite side can be used. From the known segment lengths, i.e. the distances from the knee axis to the hip rotation point and to the foot point, and the determined position of the upper part of the knee relative to the lower part of the knee, the length of the leg tendon can be calculated. The position of the leg tendon is determined, for example, by spatial position sensors and angle quantities and segment lengths, for example based on the absolute angle of the lower leg and the knee angle and the lengths of the lower leg and the upper leg. The change in position can be determined by the time derivative of the position or by the velocity and the segment length. From the position and / or length of the leg tendon and possibly its time change, the speed of movement is calculated and is the basis for the change of resistance. In the stance phase, the speed of the hip, the trunk and / or the body's center of gravity can be inferred from the leg tendon and its position and / or length change.

[0023] A further development provides that the movement speed is determined by means of a time integral of an acceleration detected by means of a sensor, for example the translational speed of the lower leg at the height of the knee joint axis or the translational speed of the torso. From the speed of one point, for example the speed of the foot or the lower leg at the height of the knee axis, the speed of another point, for example from the foot to the hip, can be inferred by means of the kinematic chain and its degrees of freedom, which can be determined by means of sensors. It is also possible to infer the speed on the basis of sensor signals, for example the speed of the foot in the mid-stance phase and thus almost at rest by means of force sensors and absolute angle sensors on the lower leg.

[0024] Alternatively or additionally, the movement speed can also be determined relative to the ground and / or the environment, for example by means of environmental sensors such as LIDAR, radar, Doppler radar or ultrasound, or navigation systems such as indoor navigation or global navigation systems such as QZSS or Galileo.

[0025] The absolute movement speed and / or one or more components, for example the component parallel to the ground or the horizontal component, can be used as the movement speed.

[0026] A further development provides that the rotational speed of the upper leg, the lower leg and / or the angular velocity of the ankle joint, the knee joint and / or the hip joint is used as the movement speed. For example, the rotational speed of the lower leg in the stance phase can be used as the movement speed for the change in resistance.

[0027] The change in resistance is in particular carried out in real time, wherein on the basis of previous data or movement profiles it is possible to estimate how future movements, speeds or loads can be, so that desired values can be preset and matched to the real-time measured parameters. Preferably, the speed and other parameters or quantities are determined in the respective movement phase itself and as far as possible in real time. The change in resistance depending on the movement speed can be prepared before the stance phase and / or carried out during the stance phase. The adjustment can be carried out once per step or per movement cycle, but also multiple or continuous resistance adjustments. The adjustment of the resistance depending on the movement speed can be limited, in particular the adjustment from step to step or movement cycle to movement cycle, or the rate of change in time.

[0028] In one design, as the movement speed decreases, the resistance level is increased by reducing the resistance later and / or more slowly. In slower movements, the later and / or slower reduction of the resistance allows a slower and more controllable movement to be carried out. Alternatively or additionally, as the speed decreases, the increase in resistance can be carried out earlier or more quickly in time.

[0029] In one development, the resistance is changed such that the movement is stopped earlier, the movement amplitude is reduced or the movement reversal is reached earlier when the speed is reduced by increasing the resistance.

[0030] In one design, a resistance that decreases with decreasing speed and / or increases with increasing speed supports in one movement direction. For example, an extension torque about the knee joint axis can be applied by an actuator. This extension torque acts as a resistance against a flexion movement and supports in an extension movement. Likewise, an elastic resistance, for example generated by a force store or an active actuator such as an electric motor, supports in the opposite movement direction. If the resistance increases with decreasing speed and / or decreases with increasing speed, the support also increases or decreases. As a speed, in particular the walking speed can be taken. In order to achieve a harmonious movement process at different movement speeds, it is not only meaningful to change the movement resistance depending on the speed, but also, alternatively or additionally, to change the support of the movement. For example, in the stance phase flexion and in the stance phase extension, it is advantageous to first apply a resistance against the flexion movement in order to achieve a controlled flexion and to support the extension movement after the movement reversal. At higher movement speeds, the user typically generates higher forces and torques with the remaining limbs and joints. For example, a higher hip extension torque is applied in the stance phase to generate a propulsion force. By means of the hip extension torque, the torque acting on the knee joint axis is also influenced, in particular the external flexion torque is reduced, while the extension torque is increased in the middle and late stance phase. Accordingly, the supportive knee extension torque in the middle stance phase can be reduced relative to slower movement speeds. The adjustment of the support can be achieved, for example, by changing the internal extension torque provided by an actuator, such as an electric motor, or by adjusting the spring stiffness, the spring zero point, the transmission ratio, the lever arm, an additionally acting damping or the switching on or off of a force store. A lower spring stiffness, damping or a smaller lever arm leads to a reduction in the resistance. It is also possible to change the resistance level by changing the resistance, for example the motor torque or the spring stiffness, earlier or later depending on the speed. This also influences the support level. In particular in movement phases that contain a movement reversal, a resistance or force or torque is provided that resists the movement in one direction and supports the movement in the opposite movement direction; the resistance provided throughout the movement phase increases with decreasing speed and / or decreases with increasing speed. The resistance can change here during the movement process.

[0031] In one design, the state of the resistance device that influences the resistance is adjusted by the control system depending on the speed. For a hydraulic throttle valve, the flow cross section can be changed, for a magnetorheological brake the applied magnetic field, or for a friction brake the braking force. It is possible here for a state of the resistance device for the resistance to the movement not to be constant, but to depend on the movement, for example in a throttle valve in which the flow resistance depends on the flow rate. Thus, the resistance comes both from the properties of the resistance device itself and from its state, which is changed by the control system depending on the speed.

[0032] In one design, the resistance change takes place in at least one movement or movement phase that is different from the stance phase of walking on a plane. In particular, the resistance change is meaningful when walking uphill and downhill, when ascending and descending stairs and / or when stepping over individual steps or thresholds, when walking backwards and / or sideways and in rotational movements. The resistance change is also advantageous when stopping and starting. Finally, the resistance change can be applied to special modes that are suitable for special movements and sports activities, such as cycling, skiing or skateboarding, in particular under load. Here, the movement speed, in particular the walking speed or the movement speed, is determined and the resistance is increased when the movement speed under load decreases or the resistance is reduced when the movement speed increases. The stance phase can be a movement phase in which the orthopedic aid bears part or all of the body weight.

[0033] In one expansion, when walking downhill on an inclined surface and / or overcoming a height difference such as a step, the resistance adjustment adapts the correlation of the advancing movement and the lowering movement of the supported side in the stance phase to the ground inclination detected by the sensor or the height difference to be overcome, or depends on it. At faster walking speeds, it is advantageous to sink or move the body downward more quickly at a given inclination or height difference. Starting from a determined correlation of the advancing and lowering speeds that are advantageous for the detected ground inclination, the resistance is increased as the movement speed decreases or reduced as the movement speed increases. In addition to the speed correlation, a correlation of the distance moved in the advancing and lowering direction within a certain time can also be used for the resistance adjustment. As a correlation of the speed or the distance moved, for example, a ratio or other functional relationship can be used.

[0034] The change in resistance can depend on the type of movement, the movement phase, the ground, the environment and / or the current operating mode of the aid. The resistance adjustment can be designed differently for ascending stairs, for example, than for walking downhill. It is also possible that the change in resistance with speed can be adjusted individually for the user, for example to adapt to the body weight or personal preferences. This individual adjustment can be made by operating elements or an app. The type and / or extent of the change in resistance can also be adapted stepwise or during the movement by the aid autonomously to achieve an adaptation to the user or to components of the orthopedic device, such as shoes or cosmetics.

[0035] In one embodiment, the resistance is a force or torque characteristic depending on the actuator motion and / or position or orthotic device component (e.g. friction, damping, elasticity, spring force, etc.). It can be a linear or non-linear behavior. Accordingly, the change of resistance can be achieved by changing the friction value, damping, stiffness, zero point, etc. Also one or more parameters of such characteristics can be adjusted to achieve a resistance change, e.g. a progression of non-linear stiffness or damping. The resistance can also be generated by a combination of multiple characteristics, e.g. elastic and damping behavior, acting in series or in parallel. The characteristics, like stiffness and damping, can also refer to other degrees of freedom than the one between the upper part and the lower part, e.g. the lower part angle relative to the gravity direction. For example, the knee extension torque can have a linear relationship to the inclination of the lower leg relative to the gravity direction, which corresponds to a linear elastic behavior, and the spring stiffness changes with the motion velocity. The resistance can also be a torque or force exerted by the actuator; this torque or force can change depending on the motion velocity.

[0036] For active electro-mechanical or piezo-electric actuators, the motion resistance or support motion can be imposed by the current and voltage. Accordingly, the voltage and / or current can be changed depending on the motion velocity. In addition to imposing a torque and force curve, by control algorithms and sensor information about the upper part pivot motion, trajectories can be tracked, target quantities can be controlled or system characteristics can be simulated, like impedance or admittance control. For example, the behavior of a linear or non-linear spring, the behavior of a damper or inertia, or a combination of multiple characteristics can be simulated, so that the motion state of the upper part and / or lower part can be influenced. Such controls provide a high degree of flexibility. By such controls, the pivot motion can also be actively supported. For example, if the actuator simulates a spring characteristic, resistance is imposed to the motion in the first place against the spring direction and supports the motion when the motion is reversed. With increasing motion velocity, the stiffness of this spring characteristic can be reduced, so that the resistance against the motion and the degree of support in the opposite motion direction is reduced. Other control strategies can also be adjusted with the motion velocity, so that with increasing motion velocity the resistance is reduced. By the actuator, also a capacity store can be activated and deactivated, e.g. a hydraulic spring store, the drive ratio of the drive can be changed and / or coupled or decoupled or locked. These types of actuation can also be used to influence the pivot motion and change the resistance.

[0037] In an extension, the sensor signal for changing the resistance is superimposed on a biological signal, which is detected by a man-machine interface (MMI) and transmitted to the control device. Thereby, the resistance, in particular the flexion resistance, can be intentionally adjusted. The control by the MMI can also be subconscious, so that it is integrated into the natural control of the central nervous system of the body movement. Thus, the resistance can be determined both by the intentional and arbitrary signals of the man-machine interface, but also by the sensor signal with regard to the movement speed and possibly additional sensor signals. In one design, the man-machine interface is a sensor device, by which electromyographic signals are detected and transmitted to the control device. By the tension of the muscle in the electrode area, the movement resistance of the orthopedic technical device, for example a prosthesis or an orthosis, is adjusted, in particular increased. This can be the tension of a single muscle, but also the tension of several muscles or one or more muscle groups. It can also be the intention of one or more muscle tensions or the influence on the movement, for example by detecting nerve pulses in the central or peripheral nervous system. It is also possible to employ as biological signals the deformation of the tissue, the electrical conductivity of the tissue, the absorption, reflection and / or propagation of acoustic and / or electromagnetic waves in the tissue, electromagnetic fields, electrical potentials, substance concentrations and electrochemical gradients in the tissue, in particular from which the control of one or more muscles can be inferred. It is also possible that methods of pattern recognition, signal processing, classification and / or artificial intelligence are applied to the detected biological signals by the MMI and discrete and / or continuous values calculated thereby are provided as biological signals to the control system. Different biological signals can be employed in different contexts, environments, operating modes, movements and / or movement phases.

[0038] In one design, in at least one movement phase, the biosignal has priority over the movement speed signal in the control device, so that without a biosignal, no change of resistance with speed occurs. The biosignal thus acts as a so-called trigger or trigger for a change of resistance. The manner of the change is then varied and adapted by an evaluation of the movement speed, possibly in combination with other sensor quantities and sensor data derived quantities. It is also possible that the extent of the influence or modulation of the resistance by the biosignal is determined by the movement speed. For example, at low speeds, a resistance adaptation by the biosignal up to complete locking is possible, while with increasing movement speed, only a smaller increase is possible. When a threshold value of the movement speed is exceeded, the resistance adaptation by the biosignal can also be completely prevented. Alternatively or additionally, the sensitivity of the resistance change depending on the biosignal is changed based on the speed, in particular meaning that the sensitivity is lower at higher speeds. The biosignal is particularly suitable for defining the point in time and / or the duration of the resistance change, while the movement speed determines the type and / or extent of the resistance change, possibly together with other sensor values and indicators. In one design, the resistance adaptation is triggered by the biosignal and maintained for a certain period of time or movement phase, even if the control by the biosignal is no longer present. In addition to a continuous modulation by the biosignal, a discrete adjustment of the resistance level is also possible, which is superimposed on a continuous or discrete adjustment with the movement speed. The control by the biosignal can be designed differently or deactivated depending on the situation, the movement process, the movement phase or the operating mode.

[0039] In one design, the movement speed is averaged over a movement phase and the average movement speed is used for the control.

[0040] The translational speed of one or more directions of the orthotic device assembly, the trunk, the body center of gravity and / or the contralateral can be determined from sensor values and taken as movement speed, in particular the speed component parallel to the ground or in the horizontal direction.

[0041] The resistance is applied counter to the movement in at least one movement phase, wherein in one design the resistance opposes the flexion movement and / or supports the extension movement in at least one movement phase. The resistance actively supports the movement when the direction of action remains unchanged and the direction of movement changes in at least one movement phase. The resistance can be adapted in a movement phase with movement reversal, wherein the resistance is applied counter to the movement in the first movement direction and supports the movement in the opposite movement direction.

[0042] The adaptation of the resistance with the movement speed is particularly suitable for the crossing of one or more steps when descending stairs, for walking downhill and / or for descending a height difference. Likewise, in one design, the adaptation of the resistance with the movement speed takes place when braking and / or stopping from the movement.

[0043] The adjustment of the resistance can take place in overcoming height differences, in particular when climbing over one or more steps and / or walking uphill on inclined ground.

[0044] In one design, the resistance increases with decreasing speed of movement until a locking or stopping of the relative movement of the upper and lower parts is reached.

[0045] In one design, the resistance is a linear or non-linear, elastic and / or damping behavior depending on the pivoting movement between the upper parts and / or the movement and / or load detected by the sensors.

[0046] The change in resistance can be achieved by adjusting one or more parameters of the elastic and / or damping behavior. The resistance changes with the speed of movement such that in at least one movement phase the horizontal and vertical speed of movement and / or the distance of the horizontal and vertical movement are related to each other, in particular in a ratio depending on the inclination of the ground detected by the sensors or the height difference to be overcome. The correlation of the resistance with the speed of movement can change depending on the operating mode, the movement, the movement phase and / or the ground.

[0047] The embodiments and extensions of the method can be combined with each other and / or with other control methods and embodiments, for example with control methods known from the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0048] Examples of the application will be explained in detail below with reference to the drawings. The drawings are as follows.

[0049] Figure 1 A schematic view of a prosthetic leg is shown.

[0050] Figure 2 The movement process and the speed determination are shown schematically.

[0051] Figure 3 The resistance curve as a function of the speed is shown.

[0052] Figure 4 The resistance and speed curve as a function of time is shown.

[0053] Figure 5 The curves of different resistances as a function of time are shown.

[0054] Figure 6 The relationship of the biosignal to the resistance curve is shown.

[0055] Figure 7 A variant of Figure 6 is shown.

[0056] Figure 8 An embodiment of the control is shown.

[0057] Figure 9 Different control characteristics of the actuator are shown. DETAILED DESCRIPTION

[0058] In Figure 1 the prosthetic knee joint is shown in a schematic view as part of a prosthesis. The prosthetic knee joint has an upper part 10 and a lower part 20, which are pivotably connected to each other about a pivot axis 15. At the distal end of the lower part 20 a prosthetic foot 60 is arranged. In Figure 1 the shown leg prosthesis configuration, on the upper part 10 a prosthetic socket or other means for accommodating a thigh stump or a means for fixation to a person is arranged or formed. Between the upper part 10 and the lower part 20 a resistance device 30 is arranged as a linear acting hydraulic actuator. In the shown embodiment the hydraulic actuator 30 is formed with a hydraulic chamber or cylinder, which is arranged or formed in a housing or base body 31. In the cylinder a piston 32 is movably mounted. The piston 32 is displaceable in the longitudinal direction of the cylinder and is fixed to a piston rod 33, which extends from the housing or base body 31. The piston 32 divides the cylinder into a plurality of chambers, which are fluidically connected to each other by hydraulic lines. The base body 31 or housing can be pivotably connected to a fixation point 23 on the lower part 20 in order to prevent the piston 32 from getting stuck when the upper part 10 is pivoted relative to the lower part 20. The piston rod 33 at its end distal to the piston 32 is fixed to the upper part 10, in the shown embodiment to an upper fixation point 21 on a bracket for increasing the distance to the pivot axis 15. Upon flexion, the piston 32 is pressed downwards, so that the volume of the flexion chamber decreases and the volume of the extension chamber increases, minus the volume of the protruding piston rod 33. In the housing 31 an electric motor can be arranged to drive a not shown pump, so that the hydraulic fluid of one of the two chambers is pressurized, so that the piston 32 is moved in the cylinder in one direction or the other. Thereby a flexion movement or an extension movement of the orthopedic device in the form of a leg prosthesis is achieved. The electric motor for driving the pump is an option, which can be used in an embodiment in combination with the hydraulic actuator 30. Basically, for a passive prosthetic knee joint a drive or motor is not necessary. The actuator 30 as a passive linear damper, in particular a linear hydraulic, alternative design is a rotational damper, in particular a rotational hydraulic, a magneto rheological resistance device or an electric motor, in particular in combination with a gear or screw transmission. The electric motor can be operated in generator mode. Also, in a configuration a combination of a plurality of the above described resistance devices as actuators is achieved.

[0059] Arranged inside the housing 31 or on the housing 31 is a drive 34, which is coupled to at least one regulating valve 35, through which the hydraulic resistance in the actuator 30 can be changed. The actuator 30, in particular the drive 34, is coupled to a control device 40, which activates, deactivates or modulates the drive 34 on the basis of sensor values, so that an adapted resistance can be provided by the passively designed actuator 30. For the design of the actuator 30 as a magneto-rheological resistance device, the resistance is changed by activating, deactivating or modulating a magnetic field, the drive 34 then being an electromagnet or a magnetic coil. For the design of the actuator 30 as an actively driven drive with an electric motor, the resistance is changed by activating, deactivating or modulating an electric voltage, which influences the torque generated by the electric motor.

[0060] Arranged on both the upper part 10 and the lower part 20 is at least one sensor 50 for detecting the spatial orientation of the lower part 20 or the upper part 10. In particular, the sensor 50 for detecting the spatial orientation is arranged only on the upper part 10. By means of this sensor 50, which can be formed, for example, as an IMU (inertial measurement unit), the spatial angle or the absolute angle relative to a fixed spatial direction, for example the direction of gravity, is determined during use of the prosthetic knee joint. Instead of as an IMU for detecting the spatial position, the respective sensor 50 can also detect other state data, in particular state data relating to the artificial knee joint. As state data, in particular the position, the angle, the speed, the acceleration, the force and their curves or changes are detected. The determined spatial angle or other state quantity of the upper part 10 and / or the lower part 20 is compared with a threshold angle. When the threshold value stored in the control device 40 for the respective sensor value or a quantity derived therefrom is reached or exceeded, the drive 34 is modulated, activated or deactivated in order to change the flow resistance, the viscosity, the braking force, the torque, the stiffness or the force against the flexion movement in the design of the actuator 30 as a hydraulic damper.

[0061] The actuator 30 in the artificial knee joint is generally used to modulate the flexion movement and the extension movement in order to produce or support a proper or desired movement process. The extension movement can be supported and advantageously braked before the maximum extension is reached in order to avoid a hard impact. The flexion movement is braked or prevented in the stance phase and the swing phase in order to ensure a flexion limitation. In order to be able to drive the drive 34 to operate the regulating valve 35, an energy store, in particular in the form of a battery, is likewise assigned to the drive 34. The energy store can be arranged directly adjacent to the drive 34 or in another position on the orthopedic device where there is more space or which is advantageous due to the weight distribution.

[0062] Furthermore, a control device 40 and at least one angle detection device are arranged on the prosthesis or orthosis as sensors 50. The angle detection device 50 detects the angle between the upper part 10 and the lower part 20 and is formed, for example, as a direct angle sensor which directly detects the angle. Alternatively, the angle between the upper part 10 and the lower part 20 can be determined by evaluating the sensor data of two spatial position sensors 50. Both methods can also be used simultaneously or complementarily. All sensors arranged on the prosthesis or orthosis are coupled to the control device 40 and their sensor values serve as the basis for controlling the drive 34 of the actuator 30 if the actuator 30 is formed as a damper, or as an input signal for the motor control if the actuator 30 is formed as an electric motor. For the case of a magneto-rheological damper, the sensor values are used to control the magnetic field or its change. Based on the sensor data, in particular the spatial and / or angular position and position data, the load, the direction, the acceleration and / or the deformation data of other components, the drive 34 is controlled to reduce or increase the pivoting resistance by the actuator 30.

[0063] Furthermore, a man-machine interface 100 is assigned to the prosthesis, by means of which biological signals from a person can be transmitted to the control device 40. The man-machine interface (MMI) 100 can be accommodated in a separate component as a switch or sensor or be part of the prosthesis. The MMI 100 transmits the biological signals to the control device 40 wired or wirelessly, so that, for example, an increase in the flexion resistance is triggered at the beginning of the stance phase, wherein this increase is modulated during the stance phase by evaluating the sensor values of the sensors 50 or at least one sensor 50. The MMI 100 thus only gives an initial signal, which is then autonomously adjusted with the support of the sensors in the movement sequence.

[0064] In Figure 2 a prosthetic leg is shown schematically, which has an upper part 10 in the form of a prosthesis socket and a joint assembly arranged thereon, and as a lower part 20 a calf part, which are hingedly connected. Inside the upper part 10 there is accommodated an MMI 80 in the form of a sensor assembly for detecting myoelectric signals. When, for example, a contraction of the thigh muscles is measured, this biological signal detected by the MMI 80 is transmitted to the control device 40 and serves to trigger a change in resistance. In Figure 2The leg tendon 70 is also drawn, which extends from the proximal hip joint rotation point 71 to the foot point 72. The resistance change by the actuator depends on the walking speed in the stance phase. The walking speed is the movement speed of the entire body in the stance phase from the heel strike (shown at time tO) to the end of the stance phase. The time t1 represents a time point at the end of the stance phase. The movement speed in the stance phase is not necessarily constant, but can vary over time. For this case, the hip or the hip joint rotation point 71 moves forward, while the prosthetic foot remains on the ground, so that the foot point 72 essentially remains stationary. The walking speed can be determined from the distance moved between two time points, for example the distance Δx in the time from tO to t1. In addition to the average speed over a longer time (by the chord S), the instantaneous speed can also be determined from the movement by the tangent T, which is shown on the right side of Figure 2 in the stance phase.

[0065] The resistance adjustment against the displacement of the lower part 10 relative to the lower part 20, in particular against the flexion in the stance phase, in particular depends on the speed at which the leg is moved. The adjustment in particular depends on the walking speed. The resistance against the flexion can be a passive resistance, for example by converting the movement energy into heat energy by means of a damper, or an active force exerted by the actuator against the movement. The resistance against a displacement in one movement direction can be actively supported in the opposite movement direction. In addition to the movement speed, in particular the walking speed, other translational or rotational speeds, for example the speed of the upper part 10 or the lower part 20, which characterize the movement speed, can also be used. Such other movement speeds can also occur when performing a movement other than walking.

[0066] The flexion resistance of the knee joint in the stance phase decreases with increasing movement speed. In Figure 3In the mean, the relation of the average motion resistance level R' to the motion velocity v is plotted. The average motion resistance level R' decreases with increasing walking velocity v, wherein saturation occurs at low and at relatively high walking velocities v, and the curves approach limiting values, respectively. It is also meaningful to decrease the flexion resistance in the stance phase with increasing velocity, for example when walking downhill on a slope. The slower the walking velocity, the longer the stance phase duration and the smaller the step length. The same applies to walking on a plane. It is therefore advantageous to select a high flexion resistance when walking slowly, in order to sink down only slowly and the prosthesis or orthosis user does not have to lift the body weight center of gravity with effort. At fast walking, due to the short stance phase duration, it is advantageous to reduce the flexion resistance, in order to enable the user to sink down deeper, for example to absorb the momentum of the body. When walking on a plane at high speed, by reducing the flexion resistance, not only the short stance phase duration is taken into account, but also the stronger propulsion hip moment. In the braking gait, at higher velocities, for example when the lower leg and / or leg tendon is rotated forward quickly, it is also advantageous to select a smaller resistance, because a high kinetic energy of the body has to be absorbed. At high velocities, it is advantageous to brake the body by a larger distance, i.e. a larger flexion angle, at a smaller resistance, whereas at lower velocities, a faster and more precise braking is advantageous. Due to the continuous decrease of the velocity during braking, this can lead to a gradual increase of the resistance, if the resistance is dynamically changed with the velocity. The feedback of the resistance on the velocity and the increase of the resistance when the velocity decreases then leads to a progressive braking and a progressive resistance curve during the motion, which can also be smoothly transferred to a locking or stance function with a very high flexion resistance. Thereby, a relaxed stance when the joint is bent can be achieved.

[0067] In Figure 4 In the mean, exemplary curves of the motion velocity v and the resistance R in the braking gait with dynamic coupling are shown. Starting from an initial velocity v and an initial resistance R, the body is braked. The velocity v is thus decreased, which in turn leads to an increase of the resistance R, so that a progressive decrease of the velocity v and thus a progressive increase of the resistance R occurs until the use position is stopped or the joint is locked, for example.

[0068] The increase of the resistance level R' depending on the motion velocity can be performed in different ways, wherein two are shown in Figure 5 In the left graph, the resistance curve is purely increased with decreasing velocity v, wherein the characteristic or the curve itself remains essentially unchanged. The dependency of the resistance level as a function of the velocity can be chosen similar to the curve shown in Figure 3 In the right graph, the curve shape of the average resistance level R' is changed, in the shown embodiment the rate of change and the point in time of the resistance change. It is also possible that the change of the resistance level depends on the operating mode, the motion type or the motion phase of the orthotic technical device. It is also possible that the change of the resistance level is only performed in certain operating modes, motions or motion phases. In Figure 5On the right, for the two different motion phases, labeled R1'(v) and R2'(v), the different dependencies of the resistance level R' on the velocity v are shown, wherein no adjustment of the resistance level with the velocity is performed in the middle motion phase.

[0069] In addition to walking on a plane, on a ramp and on an inclined ground, stepping over a step or a braking gait, an adjustment of the flexion resistance depending on the motion velocity of the person or of a part of the orthosis or prosthesis can also be meaningful in different situations than walking, for example when kneeling down, sitting down or squatting. For example, the velocity of the displacement or of the pivotal motion of the body's center of gravity or of the forward or backward rolling motion can be taken as the motion velocity and initiate a decrease of the flexion resistance when the motion velocity increases.

[0070] The adjustment of the resistance R can also involve a maximum, an average, an instantaneous or integrated quantity or other characteristic quantity. If the resistance level changes with the velocity, the resistance does not have to be constant during the motion, but can follow a curve which depends in particular on other sensor quantities. For example, the resistance increase depending on the motion velocity can be performed earlier or later during the motion or adjusted faster or slower. By changing the ratio of the low resistance region and the high resistance region, the overall level is changed. It is also possible that the flexion resistance is increased to a joint lock, wherein the point in time or threshold value of the lock can depend on the motion velocity. In addition to the lock, the actuator can exert a torque or force which is opposite and equal in size to the external torque or force, thereby achieving a force balance and stopping or preventing the motion between the upper parts.

[0071] In addition to the velocity, other determined quantities can also be taken in order to optimize the adjustment of the resistance to the motion situation, for example the joint angle, the segment angle, the leg tendon angle relative to a reference plane, the ground reaction force vector, parameters of the opposite side, the time derivative of these quantities or combinations thereof. For example, the resistance can be increased earlier at smaller knee angles when the motion velocity decreases gradually. The level, the point in time or the rate of change of the resistance change can be changed with the motion velocity. The adjustment of the level or the curve can be performed dynamically, so that the resistance can be changed continuously in terms of level and curve within a step. Alternatively, the adjustment can also be performed only once per step, so that the level is not changed within a step. Alternatively, the resistance is changed only in the initial phase of the motion and remains constant later.

[0072] The movement velocity is preferably the walking velocity taken by the user. This is in particular the velocity of the trunk, the upper body, the body center of gravity or the hip. In addition to the forward velocity, also a backward or sideways velocity can be taken. Also the rotational velocity around the longitudinal axis or the rate of change of the forward direction can be taken as velocity. Alternatively or additionally, also other reference points or reference elements can be taken to detect the movement velocity. The movement velocity, in particular the walking velocity, can be calculated or estimated from one or more segment angular velocities, e.g. the forward rotation of the lower leg in the stance phase. Also from angular velocities, e.g. based on sensors in the joints, and known segment lengths, like the length of the lower leg or the upper leg part, the movement velocity can be calculated. The movement velocity of the leg tendon, the translational velocity of the trunk and the hip can also be calculated or estimated in this way. Only one component of the velocity can be taken as movement velocity, e.g. the horizontal movement component or the component parallel to the ground. If the time interval of the movement is relevant, it can be based on a typical event in the movement or movement process, for walking e.g. the heel strike or initial contact, toe off or knee flexion. For example, by determining the hip position through the leg tendon at the initial contact and at the current point in time and the time elapsed, the average walking velocity in the stance phase can be determined. Thus, the movement velocity is the average walking velocity in the stance phase. The walking velocity can also be estimated from the relative angular velocity, e.g. the maximum knee angular velocity in the preceding swing phase. By integration of the acceleration, the velocity in the swing phase can be estimated. This is in particular meaningful if the resistance is to be adjusted according to the walking velocity at the initial contact or heel strike or during the flexion in the stance phase. Due to the high dynamics at the initial contact, it is difficult to estimate the velocity from the kinematic parameters detected by the sensors at this time. To avoid sudden transitions in the estimated velocity, it can be filtered or smoothed between the different methods. Another possibility is to estimate the movement velocity or the walking velocity from the step frequency or other gait parameters like the stance phase duration, swing phase duration, step length or step time.

[0073] In addition to the adjustment of the resistance by the movement velocity, the biological signals B of the MMI 80, 100 can be incorporated into the control. Such a combination is in Figure 6is plotted in the lower diagram. If there is no change in the bio signal B or no bio signal B is applied to the control device 40, as indicated by the dashed line in the lower diagram, for example because the muscle is not tensed, this is interpreted as a signal that no change in the resistance depending on the speed of movement is to be performed, as indicated by the dashed straight line of the resistance R in the upper diagram. Thus, in the control shown, the resistance R is at a constant level and does not change with different speeds. However, the resistance curve can also change based on other sensor signals. If, however, a change in the bio signal B is generated by the MMI 80, 100, as indicated by the increasing solid line of the bio signal B, this is an input quantity for the control device 40 to change the resistance R, in particular to increase the resistance. The basic increase in the resistance is triggered by the bio signal B, and the level of the increase in the resistance is determined by the speed v of the patient, the prosthesis, the orthosis or one of the components of the prosthesis or orthosis. The increase in the resistance takes place between tO and tl. At high speeds vl, the resistance R is increased less, while at lower speeds v2, the resistance is increased more. In the absence of the bio signal B, no adjustment of the resistance curve depending on the speed takes place in the design shown. It is particularly practical to generate the bio signal B by electrodes arranged on the patient and detecting muscle contractions or picking up nerve signals. In a variant of the control, the resistance level is modulated by at least one bio signal, for example by a proportional change in the resistance depending on the bio signal, wherein the modulation amplitude or the control sensitivity depends on the speed of movement, as Figure 6 is plotted in the lower diagram. If there is no change in the bio signal B or no bio signal B is applied to the control device 40, as indicated by the dashed line in the lower diagram, for example because the muscle is not tensed, this is interpreted as a signal that no change in the resistance depending on the speed of movement is to be performed, as indicated by the dashed straight line of the resistance R in the upper diagram. Thus, in the control shown, the resistance R is at a constant level and does not change with different speeds. However, the resistance curve can also change based on other sensor signals. If, however, a change in the bio signal B is generated by the MMI 80, 100, as indicated by the increasing solid line of the bio signal B, this is an input quantity for the control device 40 to change the resistance R, in particular to increase the resistance. The basic increase in the resistance is triggered by the bio signal B, and the level of the increase in the resistance is determined by the speed v of the patient, the prosthesis, the orthosis or one of the components of the prosthesis or orthosis. The increase in the resistance takes place between tO and tl. At high speeds vl, the resistance R is increased less, while at lower speeds v2, the resistance is increased more. In the absence of the bio signal B, no adjustment of the resistance curve depending on the speed takes place in the design shown. It is particularly practical to generate the bio signal B by electrodes arranged on the patient and detecting muscle contractions or picking up nerve signals. In a variant of the control, the resistance level is modulated by at least one bio signal, for example by a proportional change in the resistance depending on the bio signal, wherein the modulation amplitude or the control sensitivity depends on the speed of movement, as

[0074] Figure 7A control design is shown in which the biosignal B acts as a trigger for an increase in resistance and takes precedence over the adjustment of the resistance level or resistance R. If there is no biosignal, the resistance R is at an initial level, also shown by the dashed line. If control is made through the MMI and the biosignal B exceeds a threshold B0 or there is a minimum amount of MMI control, a resistance R adjustment is made that depends on the speed of movement. This is shown in the area between t0 and tl. If the biosignal is below the threshold B0 or falls below this threshold again, for example because there is no longer MMI control, the resistance R remains at the initial level or is reduced to this level. In the variant shown, a change in the biosignal above the threshold B0, as shown by the solid line in the area t0 to tl, does not lead to a further modulation of the resistance R. In this area, the resistance level is determined by the speed of movement, possibly also depending on other sensor information, such as the knee angle and axial force. When the speed of movement increases from v2 to vl, the resistance level decreases, when the speed of movement decreases, it increases.

[0075] The variant shown in the figure increases the resistance relative to the initial level by the MMI control in the presence of a biosignal and a sufficiently low speed. However, it is also possible that the biosignal reduces the resistance level relative to the initial level and that the adjustment of the resistance level to the speed of movement is superimposed, or that the extent of the adjustment of the resistance level by the biosignal depends on the speed of movement.

[0076] Figure 8Control designs are shown in the stance phase flexion and in the stance phase extension, for example when walking on a level surface, walking uphill or climbing stairs. Curves of the knee angle φκ and of the internal knee torque MK are shown not only for the first movement velocity v1 but also for a lower movement velocity v2. The lower movement velocity is also accompanied by a longer movement duration in the movement shown. The increasing knee angle corresponds to a knee flexion, the positive knee torque MK corresponds to an internal flexion torque. In the particular design, the knee torque is generated by an active actuator. The actuator is controlled in the region to from t0 to tl, or from t0 to t2 at the reduced velocity v2, such that the knee torque as a function of the knee angle changes according to a linear torsional spring characteristic, which has a neutral point at the time t0, so that no torque is generated at this point in time. Such a characteristic can be implemented, for example, by an electric motor based on a knee angle signal of the control device. During the stance phase flexion, the extension torque generated by the actuator increases according to the spring characteristic line and exerts a resistance to the flexion movement. After the movement reversal, the torque decreases again until the neutral point is reached, which occurs at the time tl or t2. In the implementation shown, the actuator exerts a flexion torque for the further extension, in order to harmonically stop the extension movement. The stiffness of the spring characteristic line implemented by the actuator increases as the movement velocity decreases, so that for the velocity v2 the stiffness is higher than for v1. This can be seen in that at the velocity v2 a higher maximum extension torque is generated, although the maximum knee flexion angle is smaller. Thus, the resistance increases as the movement velocity decreases. The torque generated by the actuator according to the spring characteristic line stored in the control, as a resistance against flexion, actively supports after the movement reversal. The adjustment of the resistance to the movement velocity in the torsional spring characteristic design also adjusts the degree of support. Such an adjustment of the resistance to the movement velocity implements a particularly harmonious movement process.

[0077] Figure 9Different control characteristics of the actuator (in the form of a rotary electromechanical drive) are shown, which act as resistive forces and influence the pivoting motion of the upper part 10 relative to the lower part 20 in the stance phase. The characteristics are shown as a relationship between one degree of freedom or sensor signal φ (here the knee angle) or its rate of change ω and the torque T generated by the actuator, relative to the pivot angle between the upper part 10 and the lower part 20. An increasing knee angle corresponds to knee flexion, a positive torque counteracts the flexion motion. On the left, a linearly elastic relationship between the generated knee torque and the knee angle is shown. The resistance against flexion decreases with increasing motion speed, by shifting the zero point on the horizontal axis towards larger knee angles. At the same knee angle, a smaller extension torque or flexion torque is generated. In the middle, likewise a linearly elastic relationship is shown, in which the slope or stiffness decreases with increasing motion speed, thus reducing the resistance against flexion, for example. With the linearly elastic characteristic, the actuator supports the extension motion. On the right, a non-linear damping characteristic is shown, in which the damping coefficient decreases with increasing motion speed, thus generating a smaller motion resistance at a constant knee angle velocity ω relative to slower motion speeds. In addition to being implemented by the electromechanical actuator, such characteristics can also be implemented by one or more springs, hydraulic or pneumatic dampers, magnetorheological resistance devices, etc. and combinations thereof.

[0078] The explanations regarding the prosthesis likewise apply to orthoses, in particular orthoses spanning the knee joint. By means of this control, in particular walking at different walking speeds is simplified and a more comfortable user experience is provided for the user.

Claims

1. Method for controlling a lower extremity orthotic joint device, which orthotic joint device has an upper part (10) and a lower part (20), which are pivotably mounted on each other in a hinged manner about a pivot axis (15), using an actuator (30), which is coupled to the upper part (10) and to the lower part (20) and influences the movement state of the upper part (10) and / or of the lower part (20), wherein the actuator (30) is coupled to a control device (40), which is coupled to at least one sensor (50) and activates, deactivates or modulates the actuator (30) on the basis of a sensor value of the at least one sensor (50), wherein at least one movement speed of at least one part of the orthotic joint device is determined from the sensor value and the actuator (30) is activated, deactivated or modulated on the basis of the movement speed in a stance phase, characterized in that The movement speed in the stance phase and the resistance are inversely related at least for a part of the movement.

2. The method of claim 1, wherein, The resistance increases when the movement speed decreases and decreases when the movement speed in the stance phase increases.

3. The method according to claim 1 or 2, characterized in that, The change in resistance only starts from a defined threshold and / or up to a defined threshold.

4. The method according to any of the preceding claims, characterized in that, The change in resistance is non-linear.

5. The method according to any of the preceding claims, characterized in that, The change in resistance is carried out with a constant or changed resistance profile by changing the resistance level.

6. The method according to any of the preceding claims, characterized in that, The change in resistance is dependent on the force, angle, position and / or torque determined by the sensor (50) or calculated from the sensor values.

7. The method according to any of the preceding claims, characterized in that, The change in resistance profile and / or resistance level is carried out individually for each stance phase.

8. The method according to any of the preceding claims, characterized in that, The movement speed, in particular the walking speed, is calculated from at least one measured angular velocity and the known leg tendon length and used as a basis for the change in resistance.

9. The method according to any of the preceding claims, characterized in that, The change in resistance is carried out in real time.

10. The method according to any of the preceding claims, characterized in that, The sensor signals for changing the resistance are superimposed on the biological signals detected by the human-machine interface (80, 100) and transmitted to the control device (40).

11. The method of claim 10, wherein, In at least one movement phase, the biological signals take precedence over the movement speed, and in the absence of biological signals, no movement speed-dependent change in resistance occurs.

12. The method according to claim 10 or 11, characterized in that, The point in time for the change in resistance is determined by the biological signals, and the manner in which the change in resistance is determined by the movement speed.

13. The method according to any of the preceding claims, characterized in that, The movement speed is averaged over one movement phase, and the average movement speed is used for control.

14. The method according to any of the preceding claims, characterized in that, The translational speed of at least one component of the orthopedic device, the torso, the body center of gravity and / or in one or more directions of the contralateral side is determined from the sensor values and used as the movement speed, in particular the velocity component parallel to the ground or in the horizontal direction.

15. The method according to any of the preceding claims, characterized in that, The resistance is applied in at least one movement phase against the movement.

16. The method according to any of the preceding claims, characterized by, The resistance in at least one movement phase opposes the flexion movement and / or supports the extension movement.

17. The method according to any of the preceding claims, characterized in that, The resistance in at least one movement phase actively supports the movement.

18. The method according to any of the preceding claims, characterized in that, The resistance is adjusted in movement phases with movement reversal.

19. The method of claim 18, wherein, The resistance is applied against the movement in the first movement direction and supports the movement in the opposite direction.

20. The method according to any of the preceding claims, characterized in that, The adjustment of the resistance to the movement speed is carried out when stepping down one or more steps, when walking downhill and / or when stepping down a height difference.

21. The method according to any of the preceding claims, characterized by, The adjustment of the resistance to the movement speed is carried out when braking and / or stopping from the movement.

22. The method according to any of the preceding claims, characterized by, The adjustment of the resistance is carried out when overcoming a height difference, in particular when stepping up one or more steps and / or when walking uphill on an inclined ground.

23. The method according to any of the preceding claims, characterized in that, The resistance increases with decreasing movement speed until the movement of the upper part (10) and the lower part (20) relative to each other is locked or stopped.

24. The method according to any of the preceding claims, characterized in that, The resistance is a linear or non-linear, elastic and / or damping behavior dependent on the pivoting movement between the upper part (10) and the lower part (20) and / or the movement and / or load detected by the sensor (50).

25. The method according to any of the preceding claims, characterized by, The change in resistance is achieved by adjusting one or more parameters of the elastic and / or damping behavior.

26. The method of any of the preceding claims, characterized by The resistance is changed with the movement speed such that in at least one movement phase the horizontal and vertical movement speed and / or the horizontal and vertical distance traveled are related to each other, in particular in a ratio dependent on the inclination of the ground or the height difference to be overcome determined by the sensor (50).

27. The method according to any of the preceding claims, characterized by, The dependency of the resistance on the movement speed changes depending on the operating mode, the movement, the movement phase and / or the ground.

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