METHOD FOR OPERATING AN ORTHOPEDIC TECHNICAL DEVICE AND CORRESPONDING DEVICE

Description

[0001] The invention relates to a method for operating an orthopaedic device that supports or replaces a first body part of a wearer and has at least one controllable actuator, wherein the method comprises the following steps: a) Determining a temporal profile of at least one parameter that allows a statement about the motion state of the carrier, from measured values ​​of at least one sensor, b) Recognizing the motion state from the at least one determined temporal profile, and c) Controlling the at least one controllable actuator depending on the recognized motion state. where, in order to recognize the state of movement, at least the temporal course of at least one parameter of a second body part of the carrier is also used.

[0002] Such methods are known, for example, from JP 2014 027978 A and EP 3 156 010 A1. Other methods for operating such an orthopaedic device can be found in JP 2012 135486 A, EP 2 863 846 A1 and DE 10 2016 114075 B3, all from the applicant's own company.

[0003] Orthopedic devices are primarily prostheses and orthoses manufactured for the extremities, i.e., arms and / or legs, of a wearer. An orthopedic device is generally fitted to a single extremity, such as a single leg or arm. If the orthopedic device is a prosthesis, it replaces at least one body part. This could be, for example, a foot, an ankle, or a knee, but also a forearm or a hand. Of course, there are also prostheses that replace multiple body parts. For instance, a prosthesis manufactured for a person with an above-knee amputation is designed to replace the knee, ankle, and foot.

[0004] An orthosis, on the other hand, supports the respective body part. This includes, on the one hand, supporting and protecting against overuse, for example, in a postoperative healing process, by limiting, for instance, the angle range in which a joint is to be used. Support within the scope of the present invention also includes support through load relief, which is achieved, for example, in sports orthoses or in so-called exoskeletons, i.e., wearable mechanical structures equipped with actuators as needed, which are used in the medical field, for example, in rehabilitation or as an alternative to a wheelchair. A limitation of the user is not necessarily required.For example, it is also possible to use such an orthosis / exoskeleton to reduce the strain on the body during physical activities, increase performance and / or reduce the risk of injury.

[0005] Especially when the first body part is a leg or the stump of an amputated leg, it is important and highly advantageous to know the user's movement state in order to adjust the controllable actuator accordingly. Recognizable movement states include, for example, climbing stairs up and down, walking on a ramp, walking and running at different speeds, standing, sitting, stepping over obstacles, or movements characteristic of routine tasks. All these different movement states often require different control methods for the controllable actuator.

[0006] It is important to distinguish between the movement state of the wearer of an orthotic device, as described above, and the movement state or motion of the respective body part. For example, while walking on level ground, the movement state of the wearer of the orthotic device does not change as long as the walking continues. The motion of the body part, such as a knee, however, changes multiple times with each step. It goes through stance phases and swing phases with different key events, such as heel strike. Recognizing and predicting these key events is also important for controlling an orthotic device and has long been established in the field.However, the invention described here primarily concerns the detection of the movement state of the wearer of the orthopaedic device and the question of how a change in the movement state can be detected and the control of the orthopaedic device can be adjusted accordingly.

[0007] The movement state of a wearer typically lasts for several step cycles, while the movement state of a body part changes on a significantly shorter timescale. This change can occur multiple times within a single step cycle. The at least one controllable actuator is preferably designed and configured to change the movement state of a body part, namely the first body part that is supported or replaced by the orthotic device. It is generally not configured to change the movement state of the wearer of the orthotic device.

[0008] A controllable actuator can be, for example, a damping element, such as a hydraulic damper. Hydraulic dampers, in particular, have valves in a fluid connection that can preferably be opened or closed continuously. This increases or decreases the cross-section of the fluid connection, thereby reducing or increasing the resistance to fluid flow and thus the damping effect of the damping element.

[0009] The controllable actuator can also be an actuating element by which a specific movement of at least part of the orthopaedic device or the entire orthopaedic device can be controlled.

[0010] This is necessary, for example, in active orthotic devices, such as active knee joints or active ankle joints, so that the joint of the orthotic device fulfills its desired function. Controllable actuators can be active or passive, regardless of whether they are damping elements or actuating elements.

[0011] Controllable actuators within the meaning of the present invention also include means and methods for stimulating the musculoskeletal system, in particular the electrical stimulation of muscles and nerves, for example by means of electrodes. These can, for example, be arranged on the skin of the wearer and stimulate muscles lying under the skin by electrical impulses. Likewise, they can be subcutaneous electrodes, for example, electrodes located near the nerve.

[0012] It has long been known in the art to control the actuator based on the detected state of movement. For this purpose, at least one sensor is used to record measurements from which at least one parameter can be determined, the temporal profile of which provides information about the state of movement. The temporal profile does not need to be detected, evaluated, and documented over an entire step cycle. The parameter could, for example, be the knee angle of a knee prosthesis or knee brace, which is measured over a step cycle and evaluated in the electronic control system. The maximum knee angle varies depending on the state of movement. The maximum flexion angle that occurs in a knee, for example, is significantly greater when the wearer of the orthotic device is climbing stairs than when walking on level ground.From this, conclusions can be drawn about the state of movement, and this information is then used to control the controllable actuator, for example in the swing phase of the leg, so that the knee performs the desired movement.

[0013] In other situations, for example, it is helpful to dorsiflex the foot during the swing phase of the ipsilateral limb when climbing stairs, i.e., to lift the toes. This significantly reduces the risk of tripping and allows for smoother stair climbing that corresponds to a more natural movement.

[0014] The extremity fitted with and supported by the orthotic device is referred to as the ipsilateral extremity. An extremity not fitted with the orthotic device is referred to as the contralateral extremity. The contralateral extremity can correspond to the ipsilateral extremity if both extremities are, for example, arms or legs. However, an arm not supported by the orthotic device is also referred to as contralateral if the ipsilateral extremity is a leg, and vice versa. For the purposes of the present invention, this preferably also applies if both are located on the same side of the body, i.e., if they are a left arm and left leg or a right arm and right leg.

[0015] Traditionally, measurements are taken via at least one sensor, from which parameters of the ipsilateral extremity can be determined. For example, the knee angle, ankle angle, various moments, relative positions of different components to each other, or velocities, accelerations, or displacements of specific points of the orthotic device relative to each other or in absolute terms can be determined. All these parameters can be used to determine the state of movement. However, a disadvantage is that the state of movement can only be determined once the measurements have been taken, i.e., only after or during the respective step. Therefore, determining the state of movement is always only possible retrospectively.Controlling the actuator based on the detected movement state always relies on the assumption that the wearer's movement state remains unchanged between steps. The movement state detected in one step cycle is considered valid for the next. Disadvantages arise when this is not the case and the movement state changes. This means that wearers of orthotic devices, such as knee and lower leg prostheses, always begin climbing stairs with the contralateral extremity. Consequently, wearers who want to climb stairs sometimes have to switch their supporting leg before reaching the stairs to begin with the correct foot, i.e., the contralateral extremity.This is cumbersome and inconvenient, and also makes it very easy to identify a wearer of an orthotic device. Maintaining the illusion of natural movement is difficult or impossible in this way. The present invention therefore aims to further develop a method for operating an orthotic device in such a way that the detection of the movement state is improved and the movement performed by the wearer of the orthotic device closely resembles natural movement.

[0016] The invention solves the stated problem by a method for operating an orthopaedic device according to claim 1.

[0017] The invention is based on the understanding that human gait, in particular, but also many other human movements, are essentially determined by the coordinated movement of different body parts, especially two extremities. For example, to take a step, the stance leg must carry the movement of the body's center of gravity and generate forward momentum, while the swing leg must position the foot in such a way as to maintain balance and enable efficient weight transfer. If, for example, a hand prosthesis is used to grasp and support a railing, this also results in movements of the shoulder and, if applicable, the rib cage.The invention utilizes the idea of ​​exploiting the relationships of such a coupling to reconstruct and control the movement of the restricted ipsilateral extremity, at least in part, from a contralateral movement of the extremity. This applies particularly, though not exclusively, to the intention of recognizing the movement state at the earliest possible time.

[0018] The orthosis's at least one actuator can be controlled, for example, so that the movement and / or support of the supported extremity, which in this case constitutes the first body part, is dependent on the movement of a contralateral extremity, which in this case constitutes the second body part. For instance, in an arm orthosis, the at least one sensor can detect leg extension from a flexed position, indicating a lifting movement. The orthosis is then actuated to support and / or perform an arm lift and / or extension movement. However, it is also possible that the orthosis provides support for the lumbar spine, which constitutes the first body part, and whose compliance can be adjusted by an actuator.The compliance is modified, for example, when a leg extension movement from a flexed position and / or a bending of the elbows from a straight position is detected, especially when the upper body is tilted forward. In both cases, the actuator's control is coupled to the movement of at least one other body part.

[0019] According to the invention, the temporal profile of a parameter is used to detect the state of motion. A single measurement, which provides a measured value at a single point in time, is insufficient. It is advantageous, but not necessary, if the temporal profile of the parameter is determined over one or, more preferably, several cycles, for example, step cycles, particularly in the case of repetitive movements. This is generally done by a plurality, preferably a large number, of individual measurements, each providing the measured value at a single point in time. These results of the individual measurements are stored and evaluated as a temporal profile. The plurality of individual measurements can be performed at equidistant intervals. The interval between two individual measurements must be small compared to the length of, for example, a step cycle, so that a temporal profile of the parameter can be determined from the plurality of individual measurements.

[0020] It is often advantageous and sufficient to determine the temporal profile of the parameter not over entire step cycles, but only over specific parts of a step cycle. To recognize a movement state, it is often sufficient to know the parameter at very specific points in time, for example, within a step cycle. These specific points in time could be, for example, the moment the heel strikes the ground or the moment the toes lift off. To determine this point in time as precisely as possible, it is necessary, or at least advantageous, to measure and determine the temporal profile of the parameter over a specific period before and after this specific point in time. This also falls under the inventive definition of a temporal profile.

[0021] Once the wearer's state of movement, and in particular their mode of locomotion, has been detected, the controllable actuator can be controlled accordingly. This preferably does not involve executing simple routines and time sequences stored in the data memory of an electronic control unit for specific states of movement. Instead, the temporal profile of the parameter of the second body part is preferably used to control the at least one controllable actuator. In this way, the body part supported or replaced by the orthotic device is moved harmoniously, naturally, and as optimally as possible adapted to the movements of the other body parts, especially the second body part.For example, a natural gait pattern is created by adapting the movement of an orthotic device, such as a prosthetic socket, to the movement of a healthy leg, which in this case forms the second body part. Alternatively or additionally, the second body part can also be an arm, whose natural swinging motion during walking or running is used to control the movement of a leg prosthesis or orthosis.

[0022] In particularly preferred embodiments, the method according to the invention makes it possible not only to recognize the wearer's state of movement as early as possible and to control the at least one controllable actuator accordingly, but also to adapt the movement of the actuator to the movement of different body parts and thus increase the wearer's acceptance of the orthopaedic device.

[0023] Preferably, the first body part does not directly border the second body part.

[0024] In a preferred embodiment, the at least one parameter is a relative position, relative movement, and / or relative velocity and / or relative acceleration and / or a relative angle of the second body part to the first body part and / or of a first part of the second body part to a second part of the second body part. Preferably, the second body part is a foot, a knee, a thigh, a lower leg, and / or a leg tendon. The second body part is preferably an unprosthetic limb or part thereof. However, it can also be advantageous if the second body part is, for example, part of an limb on which the orthotic device is attached. Thus, the second body part can, for example, be a thigh or the amputation stump of a leg on which a prosthesis is attached, the artificial knee or artificial foot of which, for example, replaces the first body part.

[0025] To determine the temporal progression of relative motion, the position of body parts relative to each other and / or their orientation in a common coordinate system relative to at least one sensor are determined at several points in time. Position is understood to include, in particular, the translational and / or rotational orientation relative to each other.

[0026] It is irrelevant whether the second body part, in particular the contralateral extremity, is also provided with another orthotic device.

[0027] Of particular interest is the hamstring of an unprosthetic leg, which represents the imaginary line connecting the foot and hip of the extremity. Key parameters of the hamstring include its orientation, length, velocity, and changes in movement. The hamstring provides information about the position of the foot of the contralateral extremity in relation to the body's center of gravity and center of gravity. It thus provides direct and indirect information about the progression, stability, and / or foot positioning of the wearer. Furthermore, the movement of the hamstring can already be measured using conventional sensors, although this is not typically employed. The movement of the proximal endpoint of the hamstring, i.e., the hip, can be calculated using existing sensors, which can be integrated into an orthotic device as described here.Good assumptions can be made about the movement of the distal endpoint, i.e., the foot of the untreated extremity, particularly during the stance phase. In During the swing phase, the movement, and in particular the position and / or the change in position, of the foot can be determined by at least one sensor.

[0028] If the proximal and distal endpoints of the tendon in the untreated leg are known, a leg angle or knee angle can be determined, for example, using known dimensions of the thigh and lower leg of the wearer of the orthotic device. This angle can be intuitively interpreted and used in control laws. The knee angle of the treated side is a proven control parameter.

[0029] Alternatively or additionally, if the leg is fitted with an orthotic device (i.e., the ipsilateral extremity), the position of the contralateral (i.e., unfitted) foot can also be determined relative to the ipsilateral foot. This can be done either exclusively within the sagittal plane or three-dimensionally. Since it can be assumed in many situations that at least one foot is in contact with the ground, a relative measurement of the distance between the ipsilateral and contralateral feet can be considered a determination of an absolute trajectory. Direct position measurement is significantly more reliable than the two-step integration of acceleration measurements, not least because of the need for correct initial conditions during integration.Of course, it is also possible to determine accelerations and moments acting on a foot and to represent these in the form of a series of measurements or a time-dependent graph. Double integration over time yields the motion. The horizontal component of the foot movement provides information about the stride length and thus also the timing of a step. The moment when the contralateral foot passes the ipsilateral foot is of particular interest. This applies to both the stance and swing phases.

[0030] The relative positions of other points to each other, for example, the ipsilateral knee axis to the contralateral foot, can also be of interest. The more sensors used, the more different parameters can be measured. Kinematic chains allow for inferences about other relative positions, thus making further parameters accessible.

[0031] In particular, segment angles of the contralateral side can be deduced from relative positions and / or relative movements, as well as relative angles in various combinations. This applies, for example, to the thigh, lower leg, or foot. From this, joint angles, such as the contralateral hip angle, knee angle, or ankle angle, can be determined.

[0032] By cleverly selecting different sensors to determine different quantities, from which the various parameters of the second body part can also be determined, it is possible, for example, to infer the contralateral leg movement.

[0033] Preferably, the at least one sensor is configured to detect an absolute angle, a relative angle, a velocity, an acceleration, a force, a pressure, a pressure wave, a torque, an electric field, and / or a magnetic field. A pressure wave is understood to include, in particular, a sound wave, especially an ultrasonic wave.

[0034] Preferably, the first body part is an ipsilateral extremity or part thereof, in particular a foot, an ankle and / or a knee, and the second body part is another extremity, preferably a contralateral extremity, or part thereof, preferably a foot, an ankle and / or a knee.

[0035] In a preferred embodiment, the at least one sensor is arranged on a component of the orthotic device and / or on the first body part and preferably also detects measured values ​​from which the at least one parameter of the second body part, in particular the contralateral extremity, is determined. Preferably, the at least one sensor is a non-contact sensor. Various measurement principles are available. The at least one sensor can, for example, determine information about the contralateral extremity by measuring the influence of electric, magnetic, and / or electromagnetic and electrostatic fields. This applies, for example, to the influence of resonant circuits or to capacitive measurements. Such sensors are known to those skilled in the art, so a detailed description is omitted.

[0036] Another operating principle of non-contact measurement is, for example, the determination of propagation times, reflections and interferences of waves that are advantageously emitted by the sensor itself or another component that is located on the orthopaedic device and / or the ipsilateral extremity.

[0037] Preferably, the at least one sensor is arranged on the second body part, preferably on the contralateral extremity, and preferably also detects at least one measured value from which the at least one parameter of the functional body part, preferably the contralateral extremity, is determined.

[0038] According to the invention, the at least one sensor therefore has at least one transmitter and at least one receiver. The transmitter emits a measuring radiation, which is advantageously ultrasonic waves or an electromagnetic measuring radiation, for example radar radiation and / or visible light and / or IR radiation. The receiver is configured to receive this measuring radiation. With such a sensor, the principles of interference measurement, triangulation, and time-of-flight measurement of different electromagnets or other measuring radiations are accessible.

[0039] Suitable measurement radiations include electromagnetic waves in the radio and microwave ranges, such as radar, near and far infrared radiation, and visible light, such as LiDAR. A suitable receiving device for visible light is, for example, a camera. If the measurement radiation is not electromagnetic, ultrasound radiation, for example, can be used. The measurement radiation emitted by the transmitter strikes the second body part, preferably the contralateral extremity, and is influenced by it. This influence can result from reflection of the measurement radiation, as well as changes in frequency and, in particular, phase. The receiving device is designed to receive this measurement radiation influenced by the second body part and to evaluate the information it contains.

[0040] According to the invention, the receiving device is configured to receive measurement radiation reflected or re-emitted by the second body part, preferably the contralateral extremity, and to determine the measured values ​​and at least one parameter from the transit time, phase shift, frequency shift, and / or interference with the emitted measurement radiation. Advantageously, the determination of the parameter and the evaluation of the measured values ​​do not take place in the receiving device, but rather in the electrical control unit, which is also used to control the controllable actuator.

[0041] These methods can be used to determine orientations, distances, positions, and, if necessary, velocities. The Doppler effect, for example, is used to determine velocities. All these methods and evaluation procedures can be used in both two-dimensional planes, such as the sagittal plane, and three-dimensional planes. Additionally, established image recognition techniques can be used to identify objects, particularly the contralateral extremity or parts thereof.

[0042] Photogrammetry or light sectioning methods can also be used to extract depth information from the measurements of at least one sensor. All these methods are preferably used in electrical control systems.

[0043] The measurement itself can be performed at a single point, in a defined plane, or within a directional area, such as a transmission cone. It is possible to cover the entire scene in a single image or to perform individual scans. This approach utilizes the fact that at least one sensor, located on the first body part or a component of the orthotic device, moves past the second body part, particularly the contralateral extremity, or vice versa. The second body part is therefore captured by the at least one sensor from different perspectives, resulting in different pieces of information.

[0044] The transmitter and receiver are preferably attached to the same body part, for example, an ipsilateral or contralateral body part. In other configurations, it is also possible for the transmitter and receiver to be located on different body parts. Furthermore, with multiple sensors, a combination of arrangements on the same and different body parts is also possible.

[0045] In a preferred embodiment, at least one transponder and / or tag and / or reflector for the emitted measurement radiation is arranged on the second body part, preferably the contralateral extremity. This is a so-called target, which, due to its geometric shape and / or material properties, is easily identifiable for the corresponding sensor technology and electromagnetic radiation and possesses clearly defined characteristics. Active and passive transponders can also be used, for example, to transmit identification information or independent measurement results as soon as they are struck by the measurement radiation. Such a transponder or target can, for example, be integrated into a band or belt that is arranged on the second body part or positioned in a garment.

[0046] It has proven advantageous to use data from the orthotic device and / or the wearer to determine at least one parameter, particularly the parameter of the second body part, preferably the contralateral extremity. This data could include, for example, distances, possible angles of rotation, or length measurements. For instance, to determine the knee angle of a contralateral leg from the tendon, it is necessary to know, at least roughly, but preferably precisely, the lower leg and thigh lengths of the wearer of the orthotic device on the contralateral side. Relative measurements of the contralateral side compared to the ipsilateral side can also be converted into absolute measurements by measuring absolute measurements of the ipsilateral side.For example, a contralateral lower leg angle corresponds to the ipsilateral lower leg angle plus the relative angle of the two lower legs to each other.

[0047] Preferably, when operating the orthotic device, at least one control variable of the at least one controllable actuator is controlled to a setpoint or a setpoint curve. Advantageously, this is dependent not only on the detected state of movement itself, but also on the parameters underlying this detection, in particular on the at least one parameter of the second body part, preferably the contralateral extremity.

[0048] The invention also solves the stated problem by means of an orthopaedic device that supports or replaces a first body part, wherein the orthopaedic device has at least one sensor and an electrical control system configured to carry out a method described herein.

[0049] As previously explained, determining at least one parameter of the contralateral extremity can be achieved by calculating the corresponding parameter from sensor data. Alternatively or additionally, missing parameters that are not directly accessible with the sensors used can be determined from existing measurements and, if necessary, a model or model assumptions. The available measurements can be from either the ipsilateral or the contralateral side. Examples of suitable models include mechanical and kinematic models that describe the respective movements of the extremity.

[0050] An example application of a method according to an embodiment of the present invention provides for the reduction of the flexion resistance of a knee prosthesis or a knee-spanning orthosis. The knee forms the first body part. This reduction, or the release of the swing phase, takes place during the ipsilateral stance phase, depending on the leg angle and / or the segment angles of the contralateral swing leg phase. It can also occur, at least partially, when walking downhill or descending stairs. The reduction occurs such that it takes place when, or only when, the contralateral foot, i.e., the second body part, is sufficiently close to the ipsilateral foot, i.e., the foot of the first body part, or has already passed it in an anterior direction.Such a targeted reduction of flexion resistance makes it possible to design the flexion resistance in the early stance phase to be higher than currently possible, or to prevent further flexion after a certain degree of knee flexion and only allow it again once the ipsilateral foot has swung sufficiently far forward. The timing of the reduction, as well as the initial flexion resistance, can also depend on walking speed, with higher walking speeds leading to a less pronounced increase in flexion resistance and an earlier reduction. For a prosthetic foot or a foot-spanning orthosis, the dorsiflexion movement and / or the resistance to dorsiflexion in the ipsilateral stance phase can be adjusted to facilitate easy rollover.In particular, a forward swing of the contralateral side from a standing position can indicate that a forward step is being initiated and that dorsiflexion is permitted and / or initiated relative to standing, which facilitates rolling over the foot.

[0051] In another embodiment, the trajectory of the ipsilateral and contralateral feet during each swing phase is directly determined from the relative distance of the ipsilateral foot to the contralateral foot, as determined by the ground contact of the opposite side. The ipsilateral foot represents the first body part, and the contralateral foot the second. In the case of a trans-tibial prosthesis or an ankle-foot orthosis (AFO), this provides information about the height difference to be overcome. This difference can be positive, i.e., directed against gravity, or negative, i.e., downward movement. The assistive device is then controlled so that the foot optimally adjusts its inclination or stiffness to the situation before initial contact.In particular, when descending, it is possible to bring the leading foot into greater plantar flexion in order to ascend upon initial contact with the forefoot. It is also possible that when ascending on the contralateral side, the ipsilateral foot performs active plantar flexion during its stance phase to raise the body's center of gravity and facilitate overcoming a difference in altitude.

[0052] For knee-spanning orthoses, in addition to the relative position of the feet to each other, the relationship between the movement of the swing leg and the stance leg can also be considered, particularly the ipsilateral and contralateral hamstring tendons. In this case, several second body parts are used. The movement pattern, especially overcoming a difference in elevation, can be determined from the relationship between these movements. Specifically, when ascending with the ipsilateral side, the knee joint can be flexed more deeply during the swing phase and / or stopped in a flexed position at the end of the swing phase extension. This facilitates overcoming a difference in elevation.It is also possible for the knee prosthesis or knee-spanning orthosis to be controlled during the swing phase so that the movement of the ipsilateral foot is in harmonious proportion to the movement of the contralateral leg and the movement of the ipsilateral thigh or femoral stump. For example, the knee joint can be controlled so that the stride length of the leading ipsilateral foot roughly corresponds to that of the contralateral stance leg. Greater ipsilateral hip flexion with constant contralateral leg movement can, for instance, lead to less knee extension or greater knee flexion.

[0053] In another example, the knee preflexion is adjusted. If the knee joint is stopped in a flexed position at the end of the swing phase when walking up ramps and stairs, as well as when climbing, the extent of this preflexion can be determined so that the ipsilateral and contralateral leg angles are in a harmonious relationship to each other at ipsilateral initial contact. The user thus determines the stride length primarily via the contralateral stance leg movement and the stride height via the ipsilateral, accessory-side hip flexion or thigh movement.

[0054] Swing phase control is also possible. The flexion and extension resistances, or the target values ​​of an actuator, in the prosthesis-side swing phase could be adjusted to create a harmonious relationship between the leg angle of the contralateral side during its stance phase and that of the ipsilateral side during the swing phase. The rolling motion of the contralateral side would thus dictate the timing of the ipsilateral side, with the ipsilateral thigh movement having a significant influence on how the prosthetic device must intervene in the movement.

[0055] In another example, the swinging motion is detected. Some assistive devices lack force sensors to determine whether the fitted side is in contact with the ground. The contralateral leg movement can indicate whether the user is walking backward, with the contralateral supporting leg rolling backward, or whether the supporting leg remains stationary and the ipsilateral side is swung backward under the body. In the latter case, with knee-spanning devices, knee flexion can be permitted or initiated, enabling ascending stairs or stepping over obstacles. A similar approach can help detect when the user moves the ipsilateral side forward, for example, from a standing position.

[0056] One important application is stumble detection. Information about the contralateral leg movement can also indicate whether the user is stumbling. This applies to stumbling in both the ipsilateral and contralateral swing phases. Detection can occur either through an abrupt stop in the otherwise continuous movement or through the swing leg lagging too far behind the opposite side in terms of the rolling motion. The type of reaction to a detected stumble can then depend on the position of the opposite side. This could involve lifting the foot and / or increasing ground clearance, or placing the foot down and / or increasing resistance to flexion.

[0057] By measuring the relative distance between the contralateral and ipsilateral feet, stride length is directly available and can be used for activity tracking or assessing gait symmetry, in addition to controlling movement. Walking speed can also be determined directly as distance covered per unit of time, instead of estimating it from the rolling velocity during the ipsilateral stance phase.

[0058] The accompanying drawings will be used to explain some exemplary implementations in more detail below. They show: Figure 1 - four different orthopaedic devices, each in a frontal view; Figure 2 - a worn orthopaedic device in a walking mode; Figure 3 - the orthopaedic device made of Figure 1Figure 4 shows a schematic cross-sectional view in three different step positions, Figure 5 shows a schematic representation of an application of a procedure described here, Figure 5 shows another example of an application, and Figure 6 shows a flowchart.

[0059] Figure 1 The image shows four different care situations from left to right. On the far left are the legs of a wearer of an orthotic device, where the contralateral extremity 2 is the left leg, while the ipsilateral extremity 4 is the right leg. The leftmost illustration of the Figure 1 A leg prosthesis comprising a femoral shaft 6, a knee joint 8, a lower leg 10, and a foot 12 is arranged on the ipsilateral extremity 4. The schematic representation shows that a sensor is located on the lower leg 10, which emits a measuring radiation 14 towards the contralateral extremity 2.

[0060] In the adjacent illustration, the contralateral extremity 2 is again an unprosthetic healthy leg, while the ipsilateral extremity 4 this time has a lower leg prosthesis. It has a lower leg stem 16 to which the lower leg 10 and the foot 12 are attached. A sensor is also located here, which emits the measuring radiation 14 towards the contralateral extremity.

[0061] The third illustration from the left shows a healthy contralateral extremity 2 and a fully developed ipsilateral extremity 4, on which an orthotic device in the form of an orthosis is attached. It has a thigh frame 18, a lower leg frame 20, and a knee joint 22, on which a controllable actuator is located. Here, too, the sensor is located in the lower leg region, i.e., on the lower leg frame 20, which emits the measuring radiation 14 towards the contralateral extremity.

[0062] In the far right representation of the Figure 1 The ipsilateral extremity 4 is as shown in the leftmost illustration. In contrast to the leftmost illustration, however, the contralateral extremity is also fitted with an orthotic device, namely a lower leg prosthesis corresponding to the orthotic device shown in the second illustration from the left. Both orthotic devices now each have a sensor that emits measuring radiation 14 towards the other extremity. For the orthotic device that is in Figure 1 If the left side is shown, i.e., the right leg, the opposite side is the contralateral extremity, even if it is equipped with an additional orthotic device.

[0063] Figure 2The diagram shows the representation during a gait cycle. The contralateral extremity 2 is unprosthetic, while the ipsilateral extremity 4 has a thigh prosthesis with femoral shaft 6, knee joint 8, lower leg 10, and foot 12. While the sensors in Figure 1 The sensor is located in the following directions: the measuring radiation 14 is emitted medially, i.e., almost exclusively to the side. Figure 2The sensor is configured to transmit the measurement radiation 14 towards the contralateral extremity 2, even though the latter is located almost entirely in front of the ipsilateral extremity. This can be achieved, for example, by making the transmission range into which the sensor emits the measurement radiation 14 large enough that, regardless of the position of the contralateral extremity 2, sufficient measurement radiation 14 reaches the contralateral extremity 2. Alternatively, the sensor, or in particular the transmitting device, can be rotated or moved. Alternatively or additionally, the radiation pattern of the corresponding sensor can also be adjusted.

[0064] This is in Figure 3The diagram shows the foot of the contralateral extremity 2 and, in a cropped top view, the foot 12 of the ipsilateral extremity 2 in different phases of a step. The ipsilateral extremity 4 is currently performing the swing phase, while the foot of the contralateral extremity 2 is firmly planted on the ground. In the leftmost image of the Figure 3 The ipsilateral extremity has just lost contact with the ground and the swing phase begins. The measurement beam 14 is emitted strongly forward, as the translateral extremity is located in this direction. In the middle of the swing phase, which is in the middle of the Figure 3 As shown, the ipsilateral extremity 4 is located directly next to the contralateral extremity, so that the measurement radiation 14 is emitted almost completely to the side. At the end of the swing phase, which is on the right in Figure 3As shown, the foot of the ipsilateral extremity 4 is located in front of the foot of the contralateral extremity 2, so that the measurement radiation 14 is emitted to a large extent to the rear.

[0065] Figure 4 This is an example of how the first body part 24, which in the illustrated embodiment is the right arm of the wearer, does not necessarily have to be "opposite" the second body part 26, which in the illustrated embodiment is the left ankle. Figure 4 shows three positions within a step cycle, in each of which the position of the second body part 26, i.e., the left ankle, is determined relative to another body part, namely the right ankle. In the left illustration of the Figure 4The second body part 26 is located behind the carrier's torso. The same applies to the first body part 24. The relative position of the second body part 26 to the right ankle is determined, as indicated by the three small lines. During a gait cycle, the position of the second body part 26 relative to the right ankle changes via the line in the middle of the Figure 4 positions shown within the swing phase up to the point in Figure 4 The position shown on the right is that of heel strike. The movement of the first body part 24, which is replaced by an arm prosthesis, is controlled accordingly.

[0066] Figure 5This is an example of how the second body part 26, on which a sensor 34 for determining the state of movement, in particular the stance phase of the gait cycle, is attached, can be located on the same side of the body as the body part 24, which is equipped with an orthotic device. This device—as in the case of an inertial sensor, for example—can acquire information about the state of movement solely based on measurements taken by the extremity 26 equipped with the sensor 34. Likewise, the sensor 34 attached to body part 26 can also receive measurement beams emitted, reflected, or re-emitted by the opposite leg.

[0067] Figure 6Figure 1 shows a schematic flowchart for a procedure described here. Parameters are determined from a first body part 24 and at least one second body part 26, and their temporal profile 28 is determined. From this, both a movement state 30 of the carrier and a movement intention 32 are determined, whereby the determined movement state 30 can also be used to determine the movement intention 32. Both the movement intention 32 and the determined movement state 30 can be used separately or in combination to initiate the actuator control 34. Reference symbol list

[0068] 2 Contralateral extremity 4 Ipsilateral extremity 6 Femur shaft 8 Knee joint 10 Lower leg 12 Foot 14 Measuring radiation 16 Lower leg shaft 18 Femur frame 20 Lower leg frame 22 Knee joint 24 First body part 26 Second body part 28 Temporal course 30 Movement state 32 Movement intention 34 Sensor

Claims

1. A method for operating an orthopedic device which - supports or replaces a first body part (24) of a wearer, and - comprises at least one controllable actuator, wherein the method comprises the following step: a) determining a chronological profile (28) of at least one parameter, which allows for a conclusion to be drawn about a movement status (30) of the wearer, from measurement values of at least one sensor (34), b) detecting the movement status (30) from the at least one determined chronological profile (28), and c) controlling the at least one controllable actuator depending on the detected movement status (30), wherein at least also the chronological profile (28) of at least one parameter of a second body part (26) of the wearer is used to detect the movement status, wherein the at least one sensor (34) comprises at least one transmission device and at least one reception device, wherein the transmission device emits measuring radiation (14) and the reception device is configured to receive measuring radiation (14), characterized in that the reception device receives measuring radiation (14) reflected or re-emitted by the second body part (26), and the measurement values and the at least one parameter are determined from a transit time, a phase shift, a frequency shift and / or interference with the emitted measuring radiation (14).

2. The method according to claim 1, characterized in that the second body part (26) does not directly abut the first body part (24).

3. The method according to claim 1 or 2, characterized in that the at least one parameter is a relative position, relative movement and / or relative speed and / or relative acceleration and / or relative angle of the second body part (26) to the first body part (14) and / or of a first part of the second body part (26) to a second part of the second body part (26).

4. The method according to one of the preceding claims, characterized in that the at least one sensor (34) is configured to detect an absolute angle, a relative angle, a speed, an acceleration, a force, a pressure, a pressure wave, a moment, an electrical field and / or a magnetic field.

5. The method according to one of the preceding claims, characterized in that the first body part (24) is an ipsilateral limb (4) or a part thereof, particularly a foot (12), an ankle and / or a knee, and the second body part (26) another limb, preferably a contralateral limb (2) or a part thereof, preferably a foot (12), an ankle and / or a knee.

6. The method according to one of the preceding claims, characterized in that the at least one sensor (34) is arranged on a component of the orthopedic device or on the first body part (24) and at least also detects measurement values from which the at least one parameter of the second body part (26) is determined.

7. The method according to one of the preceding claims, characterized in that the measuring radiation is ultrasonic waves and / or electromagnetic measuring radiation, especially preferably radar radiation and / or visible light and / or infrared radiation.

8. The method according to one of the preceding claims, characterized in that at least one transponder and / or a tag and / or a reflector for the emitted measuring radiation (14) is arranged on the second body part (26).

9. The method according to one of the preceding claims, characterized in that data of the orthopedic device and / or the wearer is used to determine the at least one parameter, especially to determine the at least one parameter of the second body part (26).

10. The method according to one of the preceding claims, characterized in that at least one control variable of the at least one controllable actuator is controlled to a set point or a set point profile, which is dependent on the detected movement status (30) and the at least one parameter of the functional body part, preferably the contralateral limb (2).

11. An orthopedic device for arranging on an ipsilateral limb (4), the orthopedic device comprising at least one sensor (34) and one electric control unit that is configured to conduct a method according to one of the preceding claims.