FR2716777A1 - Member of foot-ground interface to assist the muscular work of a human being. - Google Patents

Abstract

An exoskeletal system for assisting a user with carrying a payload while moving on the ground includes a right leg limb attached to the user's right foot to transmit loads directly to the ground. by said right leg member, a left leg member attached to the user's left foot so as to transmit loads directly to the ground by said left leg member, a right foot member, a left foot member, an apparatus to store and restore the energy connected to each foot member and a payload / user link connected to the payload and to said right and left leg members to guide the movement of the device. It further relates to a method of controlling this exoskeletal system.

Description

FOOT-FLOOR INTERFACE MEMBER TO ASSIST WORK

MUSCULAR OF A HUMAN BEING

TECHNICAL FIELD OF THE INVENTION

  The present invention relates to systems for developing the ability of a human to walk, jump, apply loads, carry loads, or the like, and more particularly to exoskeletal systems connected to a human operator in a limited number of of points, but including the feet of the operator, and which serve to develop the ability of the operator to transport and transport loads, including the device itself, that the operator may wish to wear. Different technologies have been developed over the years to quickly and efficiently transport a human being from one place to another. In the same way, there is considerable technology to perform other otherwise difficult tasks, such as lifting and carrying heavy loads. However, in some applications, existing technologies are unsuitable, as circumstances lead to preventing access to a machine that could otherwise transport the human and / or perform the desired task. To cite just one example, it is generally accepted that in many contexts the well-equipped first-aid worker, sportsman, mountaineer, and others can play an indispensable role in their ability to cross otherwise insurmountable terrain and accomplish of the

  tasks that go beyond the capabilities of machines.

  It has long been desired to develop a technology that would increase the ability of a human being to walk and perform various tasks, such as lifting and wearing various types of equipment.

charges while standing.

  Several attempts have been made in recent decades. A system of this type, called Hardiman, was developed several decades ago by General Electric, and includes a clothing identical to that of a robot that the operator wears all over his body and that he controls by 'intermediate

  of a series of actuators and servo-controllers.

  The suit is bulky, technically complex and inflexible. Only the arms of the coat have bilateral capacities, the legs of the machine being used as simple structures of

  support based on a slave-slave system.

  More recently, a system called Pitman has been proposed by the American Advanced Weapons Group

  Technoloqv Group of the Los Alamos National Laboratory.

  This system, like its predecessor Hardiman, includes a wear worn by the user. Unlike the Hardiman suit, the Pitman is more flexible and has many subsystems that offer protection against piercing bullets, biological and chemical weapons, and nuclear and laser effects. The Pitman proposal does not explain how to control the movement of the habit. Other developments have been made in the creation of an anthropomorphic structure that will improve the capabilities of a human being, without however involving cumbersome and inflexible clothes, but rather including elements somewhat remote from the operator, allowing the operator to bend, run, and easily perform other different body movements, virtually without

constraint on the part of the system.

  Efforts to develop this type of exoskeletal systems have been mainly limited to the development of mechanized arms. The work done by Stephen Jacobsen, at the University of Utah, on an anthropomorphic arm with 10 degrees of freedom,

  hydraulically actuated, is an illustration. The arm is remotely controlled slave type and corresponds

  one-to-one with his master. The master reflecting the load is equivalent to the arm of the operator. When the slave grabs an object, the exoskeletal master applies loads to the arms and fingers of the operator that are directly proportional to the loads applied to the object. A disadvantage of this system, which is found on all master / slave systems, lies in its great complexity, which requires, as it stands, two sets

  actuators, sensors, and electronics.

  More recently, H. Kazerooni, first at the Massachusetts Institute of Technology, and more recently at the University of California at Berkeley, developed mechanized arms using slave-based systems. . The "actuated" extenders increase the natural strength of the user's arm.The physical contact at the interface between the extender and the operator allows the transfer of mechanical power and information signals. This is ensured without a joystick, keypad, or master / slave system.In Kazerooni's system, the user enters his arm into a rubber cylinder inside the extender.Piezoelectric force sensors, placed between the the outer casing of the extender, detect interactive loads between the user's arm and the machine, and a second set of force sensors to determine the weight and acceleration of the manipulated load. dynamic movement of the operator, adapting

  the impedance of the machine to that of the operator.

  Because the reflection of charqe intervenes naturally, the human arm feels a reduced version of the charges

applied to the extender.

  Although the Kazerooni charge control system is significantly less complex than previous systems, such a system can not be applied to increase the user's leg skills, which require a more sophisticated system to capture and interpret correctly. the

  stability problems inherent in such a system.

  In many applications, it is the improvement of the operation of the user's legs, such as the ability to walk quickly and for a prolonged time, which is the important point. These systems allow the user to

  detect the center of gravity of the whole man-

  machine and dynamically couple the user to the machine. At least one system has been developed to improve the capabilities of the user's legs. The system, known as Spring Walker, is described in U.S. Patent No. 5,016,869. The Spring Walker is characterized by I0 leg extensions connected to a set of springs and pulleys that alternately store and release the spring. energy needed to produce efficient locomotion. The Springwalker, which includes a pair of rear-facing joints, allows jumps equivalent to those of the trampoline and large steps, using the energy storage springs, the user being supported by the machine. The control of the device is achieved by a mechanical connection

  direct between the user and lamacnine. Although the

  Although it is useful in certain specific contexts, the Spring-Walker suffers from a stability problem in the rest position.

  The device itself is unstable when not in motion. In addition, the coupling of the user and the machine is such that the freedom of movement of the user is very limited.

  There is thus a widely recognized need, and that it would be extremely advantageous to satisfy, from an exoskeletal system to the controlled impedance to improve the user's ability to walk, run, jump, etc., which would provide a amplification of the mechanical load, including, for example, the ability to carry payloads, including the weight of the system itself and at least a portion of the user's weight, which will ensure balance and stability, and user can

  put on and take off quickly and easily.

SUMMARY OF THE INVENTION

  In accordance with the present invention, there is provided an exoskeletal apparatus for assisting the user in carrying a payload while traveling on the ground, comprising: (a) a right leg member connected to the user's right foot so as to transmit directly to the ground loads of the right leg member; (b) a left leg member connected to the user's left foot so as to transmit loads of the left leg limb directly to the ground; and (c) a payload / user link connected to the load and, in addition, to the right leg member and the left leg member, said payload / user link being positioned so that the loads exerted by the user on the payload / user link act to guide the

movement of the device.

  In the preferred embodiments of the invention, the limbs of the legs are connected to the limbs of the feet, which are attached to the feet of the legs.

the user.

  Further, in accordance with the present invention, the exoskeletal apparatus for assisting a user to carry a payload while on the ground further includes: (1) a pair of sensors for sensing loads between each leg member and the foot respective user; (2) a pair of sensors for detecting loads between each leg member and the ground; (3) a sensor for detecting loads between the user and the payload / user link; (4) an actuator for the right leg limb; (5) an actuator for the limb of the left leg; (6) a control system connected to the sensors and actuators to control the movement of the apparatus. According to still other features of the foregoing preferred embodiments, the right leg limb and the left limb each comprise a footrest placed substantially between the user's foot and the ground, and at least two segments, said segments being connected to each other. to one another by a hinge, and the payload carrying member includes an apparatus for partially supporting the

less the weight of the user.

  The present invention thus satisfactorily overcomes the drawbacks of currently known configurations by proposing a relatively flexible and easy to deploy impedance-controlled exoskeletal system, which is capable of improving the walking, running, jumping and load-carrying capacities. and use of charges, and who has a

  adequate balance and stability.

  BRIEF DESCRIPTION OF THE DRAWINGS AND APPENDICES

  The invention is described herein by way of example only, with reference to the appendices and the accompanying drawings in which: FIG. 1 is a side view of an apparatus according to the present invention, as it appears when the user is in a standing position; Fig. 2 is a view of the apparatus of FIG. 1, when the user walks; Fig. 3 is a view of the apparatus of FIG. 1, when the user walks or runs; Fig. 4 is identical to FIG. 3, but shows, in addition, the apparatus for supporting a portion of the weight of the user; Fig. 5 is identical to FIG. 3, but in addition shows secondary machine pads placed under the feet of the user; Fig. 6 is a schematic side view of an apparatus according to the present invention showing the interfaces between the user and the apparatus, and between the apparatus and the ground or the payload;

  Fig. 7 is a schematic description of

  constituent elements of an apparatus according to the present invention;

  Fig. 8 is a schematic description of

  certain key components of an apparatus according to the present invention FIG. 9 illustrates the general concept of the master / slave system; Fig. 10 illustrates the general concept of a system according to the present invention, in which a human being directly controls a slave;

  Fig. 11 is a schematic description of

  tracking with impedance control; Fig. Figure 12 shows the system of Figure 11 in an ideal state; Fig. 13 is a front sectional view of an apparatus carrying a passive payload, according to the present invention; Fig. 14 is a side view of the apparatus of FIG. 16; Fig. 15 is a front view of the apparatus shown in Figures 13 and 14, showing construction details; Fig. 16 is a side view of the apparatus of FIG. 15; Fig. 16A is a view of the entire hip of the apparatus of Figures 15 and 16; Fig. 16B is another view of the entire hip of FIG. 16A; Fig. 16C is a view of the shoe portion of the apparatus of Figures 15 and 16; Fig. 16D is another view of the shoe part of FIG. 16C; fig. 17 is a side view of a shoe showing an energy storage device attached to the sole; Fig. 18 is a bottom view of the shoe of FIG. 17; Fig. 19 is a side view illustrating the elastic member 74 of FIG. 6, sandwiched between the interface 48 of FIG. 6 and the ground; Fig. 20 is an illustration of the load, payload stabilizer 68, resilient member 90, and frame 14 of FIG. 6; Fig. 21 is a detailed side view illustrating the association between the payload frame 14 and the belt 56 of FIG. 6; Fig. 22 is an illustration of an exoskeletal apparatus constructed and operating according to another embodiment of the invention which is intended to facilitate the pedaling action of a human user; Fig. 23 is an illustration of the connector of FIG. 6; Fig. 24 is a schematic vector illustration of the basic structure of a control system used in the operation of the present invention; Fig. 25 is an ideal schematic illustration of the system shown in FIG. 24; Fig. 26 is a schematic illustration of the operation of the apparatus according to the present invention fixed on a shaping bicycle; Fig. 27 is a schematic illustration of a control system involved in the operation of the apparatus, when it is attached to the shaping bicycle; Fig. 28 is a schematic illustration of the servo speed loop based on the

CTT method.

  Annex A is a software simulation of an exoskeletal device used to facilitate action

stationary pedaling.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS

  The present invention relates to an impedance-controlled, exoskeletal robotic apparatus that can be used to enhance the fitness of a

  user to walk and carry payloads.

  The principles and operation of an improved, impedance controlled, walking exoskeletal apparatus according to the present invention will be better understood by reference to the drawings and

accompanying description.

  Referring to the drawings, FIG. 1 illustrates a possible embodiment of an apparatus according to the present invention, with the user in a standing position. The apparatus includes a right leg member 10 which is preferably attached to its bottom portion in a manner appropriate to a right foot member 18 which is, in turn, suitably secured to the right foot of the user. The positioning of the right leg member 10 and the right foot member 18 is such that the loads of the right leg member 10 can be transmitted directly to the ground, each time the right foot member 18 is in contact with the ground, without have to transit through any part of the user's body.

  In the description and the claims, the

  term "ground" is used to indicate the part of the environment of the user who is interacting with the members of the feet of the apparatus. In most cases, this will be the surface of the soil. In other cases, however, the "floor" may be, for example, the pedal of a bicycle, the bar of a ladder, and the like. The term "soil" is used singly for convenience, and does not

  for the purpose of limiting the object of the present invention.

  The apparatus also includes a left leg member 12, which may be attached to a left foot member 20, similar to the right leg member 10 and the right foot member 18, and preferably identical

to them, in every way.

  As best shown in FIG. 6, each leg member 10 and 12 is directly or indirectly connected, near their upper ends, by a suitable connector 25, which may be active or passive, and which may comprise other components, to a load frame 14 which is, in turn, connected to the user via a frame / user interface 42, as well as a load 40 through a rack / payload interface 16. The links are such that at least a portion of the payload load is transmitted to the right leg member 10 or the left leg member 12, when direct or indirect contact occurs between one or both leg members and floor. In this way, at least part of the total load is transmitted directly to the ground without any part of the user's body being requested.

to carry the load.

  The frame / user interface 42 is preferably connected to the user, for example by attachment to the back of the latter, so that the loads, which combine forces and moments, exerted by the user on this interface 42 act to guide the movement of the device. Figures 1 to 6 show the frame / user interface 42 attached to the back of the latter. Other locations are also

  possible, as described below.

  Each of the leg members 10 and 12 preferably comprises at least two segments 22. The two adjacent segments 22 of a leg member, 10 or 12, are connected to each other by a hinge 24, which can be passive or active, rigid or flexible, and which may comprise one or more components, as described in more detail below. The segments 22 may be of the telescopic type, with one segment sliding in the other, or with respect to it. In this case, the articulation 24 constitutes the point of interaction of the telescopic segments 22. The configuration described allows the user to easily kneel,

  posing one or both knees on the ground.

  Each of the leg members 10 and 12 is preferably secured near its outer end to the leg members 18 and 20, preferably located substantially between the user's foot and the ground, or at least by sharing with the feet. of the user an area of contact with the ground for

  allow the transmission of loads on the ground.

  Figures 1 to 4 describe an apparatus according to the present invention such that it could be when door

  by a user in different positions.

  The user shown in Figure 1 is in the rest position. Here, it is desirable that the apparatus provides the stability of the user, and his own, and communicates to the user information on the position of the center of gravity of the man / machine together to allow the user to intervene to stabilize the whole. Stabilization can be achieved by any system of

  appropriate inertial stabilization, including, but not limited to, systems incorporating gyroscopes.

  FIG. 2 represents a typical operating position in which, in addition to stabilizing the assembly, the apparatus must also facilitate

  the interaction between the user and the ground.

  Figures 3, 4 and 5 show a typical walking or running position. In this case, the device must correctly assimilate the load produced by the weight of the user, his own, and that of the payload. In addition, the device intervenes to

  stabilize the payload relative to the user.

  The apparatus of FIG. 4 is characterized by a carrier 30, generally in saddle form, for supporting at least a portion of the user's weight, to further enhance the user's ability to move more faster and longer. Figure 5 shows the apparatus of Figure 3 with additional hinges which tend to further separate the user's feet, which

  s rest on an upper part 32 of the

  feet, soil, which comes into contact with the lower portion 34 of the footrest, spaced from the upper portion 32. Such a configuration indeed extends the legs of the user who can move

faster.

  In a preferred embodiment of an apparatus according to the present invention, shown in FIG. 6, and described in part above, the b & ti / payload interface 16 is placed near the user's back to support a payload. The rack / payload interface 16 is, in turn, supported by the payload rack 14 which is fixed by an interface

  frame / user 42, on the back of the latter.

  Each leg member, 18 and 20, preferably comprises a structural member 44 connected to the corresponding leg member, 10 or 12, and a pair of interfaces: user interface / structural member 46 and structural member interface / floor 48. Each of these interfaces may comprise different active or passive components and preferably comprises one or more force sensors for measuring one or more forces, or one or more moments. The force sensors preferably measure three forces

and three moments.

  The configuration illustrated in FIG. 6 enables the system to detect the load exerted by the payload 40, and by the apparatus and the user, and authorizes the necessary corrections so that the loads generated by the payload 40 do not interfere with the load. 'user. The corrections are preferably made by a series of actuators (not shown), placed in all appropriate places, including, but not limited to, the right of the joints 24 between the adjacent segments 22. The signals sent by the different sensors force are received and analyzed by a control system, described in more detail below, which generates commands towards the various actuators to enable the apparatus to

working properly.

  Figure 7 schematically describes the entire system. The complete system comprises the user, the machine, the payload, and a series of interfaces between the machine and the user, between the machine and the payload, and between the machine and the ground. Charges are transmitted in both directions at each interface. The system also preferably includes a power supply to increase the

  power of the user's muscles.

  Figure 8 shows some components of the machine. The sensor data is routed to a CPU that calculates the desired paths of the different links, which links may be rigid or flexible. The information is used to drive a servo control unit that sends appropriate commands to the various actuators, which may include different hydraulic pistons, pneumatic pistons, or both. The feedback sensors close the feedback loop, monitoring the activity of the actuators and sending the information to the servo drive. Actuators generate forces that control different mechanisms which, in turn, drive the

  different links in the desired way.

  Unlike a master / slave system, the system according to the present invention requires user movements to directly activate the machine. Figure 9 shows a typical master / slave system. In such a system, commands from the user drive the master. The master, in turn, controls the slave in interaction

with the environment.

  In contrast, in a system according to the present invention, diagrammatically illustrated in FIG. 10, there is a direct dynamic interaction between the user and the slave. The system is controlled using an impedance control, in passive mode or actuated. The advantage of this system lies in its simplicity, thanks to the absence of a master unit which normally greatly complicates the system, requiring a second set of sensors, actuators, and

associated equipment.

  Figure 11 shows schematically a possible impedance control. The user generates certain forces that are detected by load sensors. The signals emitted by the load sensors are then analyzed, and the impedance control subsystem transmits speed commands to the servo loop, which interacts with the environment. Speeds produced by the servo loop are returned to the user to provide the user with the real-time status of the man / machine set. FIG. 12 shows an ideal system, including suitable sensors, which instantly control the servo loop,

  as well as a model of impedance with perfect precision.

  In a set of system embodiments according to the present invention, the device is passive in that it does not include actuators or power supply. Figures 13 to 16 illustrate such embodiments. Figures 13 and 14 are, respectively, simplified front and side views

  a device used to carry payloads.

  The device incorporates a pair of leg members, 110 and 112, each of which is connected at its lower end to a leg member, 118 and 120, which are, in turn, securely attached to the feet of the leg. user, so that the loads on one leg member, 110 or 112, or both, are transmitted directly to the ground, whenever the user's foot is fixed to said foot member

contact with the ground.

  The upper ends of the leg members, 110 and 112, are suitably connected to a harness 150 or frame which, in a preferred embodiment, surrounds the user at the waist, and is preferably connected to in a suitable way to the user. The harness 150 can accept a payload (not shown), for example, by attaching the payload to the harness with a strap.

  , or placing said load on said harness.

  The operating principle of this type of payload carrying device is that, at any time, and when the user moves while walking, at least one leg of the user is in contact with the ground. Since the foot members are suitably attached to the user's feet, whenever one of these comes into contact with the ground, the corresponding foot member also comes into contact with the ground, thereby allowing transmission of loads supported by the corresponding leg member. The leg members are connected by a common harness which, in turn, supports the payload to be transported. An appropriate design

  of the system, as described in more detail below.

  below, ensures the movement of the weight of the system, including payload, when the feet of the user, alternatively, make contact with the ground and rise from the ground. The displacement of the load is accomplished in a manner analogous to the operation of the human hip joint, such as

  described in more detail below.

  FIGS. 15 and 16 show, respectively, a more detailed version of a payload carrying device, generally described above, in front and side view, as well as in close-up views of parts of the apparatus

illustrated in Figures 16A-16D.

  The apparatus comprises a load support frame 400 on which a plurality of loads (not shown) can be attached or placed in a suitable manner. A hip stabilization assembly 402, described in more detail below with reference to Figs. 16A and 16B, is rigidly attached to the load support frame 400. The hip stabilization assembly 402 is connected by a hip joint 404, to a thigh pin 406, which in turn is connected to a knee joint 408. The knee joint 408 connects the leg 406 to a pin 410 which is, in turn, connected to an ankle joint 412. The ankle joint 412 is rigidly connected to the user's shoe 444, preferably at the heel of the

shoe 412.

  The load support frame 400 (not shown in Fig. 16 for clarity) is preferably rigid. The interface between the user and the load support frame 400 is preferably located at the wearer's waistband, including the back area. The interface is preferably provided by a series of well located trunk contact plates 414. The contact plates 414 are positioned to allow the user to transmit to the load support frame 400 the forces

  horizontals necessary to guide the device.

  The contact plates 414 are placed so as to allow a relatively free vertical clearance between them and the user, so that none of the vertical loads associated with the payload

  supported can not be transmitted to the user.

  As will be seen, each time the user lifts one of his legs off the ground, the part of the apparatus on the side of the leg raised has a strong tendency to crash under the combined weight of the load and the weight of the device itself. To overcome this disadvantage, a hip stabilization assembly 402 is used, shown in more detail in FIGS. 16A and 16B. The hip stabilization assembly 402 includes an upper limb 420, a portion of which is rigidly connected to the load support frame 400, via a pair of bolts 422, which secures a portion of the load support frame. 400 in a slot 424, arranged

  in a portion of the upper limb 420.

  The lower portion of the upper limb 420 is pivotally connected, on a transverse joint 426, to an upper arm 428 extending from the hip joint 404. It should be noted that the pivot axis of the transverse joint 426 is perpendicular to that of the hip joint 404. The combination of the two pivots allows a circular movement with two degrees of freedom between the frame of

  support of the load 400 and the leg 406.

  To neutralize the tendency of the apparatus to collapse on one side when the user lifts his leg, the following device is proposed. An insert 430, bolted to the upper arm 428, extends laterally so as to be substantially parallel to and placed below an extension of the upper limb 420. The extension of the upper limb 420 is connected to a disc 434 by a connector 432, which may be an adjustable screw, which passes through the insert 430. Between the disk 434 and the insert 430, and between the insert 430 and the extension of the upper member 420, there are appropriate load-damping elements like, for example, different rubbers,

springs, and the like.

  Hip stabilization assembly 402 operates as follows. When the user lifts one leg off the ground, the part of the apparatus placed on the side of the leg lifted tends to fall, or to rotate around the other foot towards the body of the user. The downward movement causes a pivoting movement about the hinge point 426. However, the pivoting movement is damped and largely eliminated by the resistance of the damping elements which come into play when the insert 430 approaches the extension of the upper limb 420. In this way, the hip is stabilized by preventing it from falling while the user's leg is not in contact with the ground. In the same way, when the user raises one leg and bends his knee to bend down, the knee joint 408 flexes. It is important that the knee joint straighten up before placing the back of the foot on the floor. To do this, the apparatus is provided (see FIGS. 15 and 16) with a pair of leg guides 436, which are connected to thigh stems 406, so that a forward movement of the thigh of the thigh The user pushes a thigh guide 436, then thigh leg 406, also forwards. The flexion of the knee joint 408 causes the stretching of an elastic member 438, which may be an elastic band, such as a bungee cord, and which

  is attached to the thigh stalk 406 and the stalk 410.

  The elastic member 438 is preferably guided by a guide roller 440, mounted, for example, on the leg 406. As the elastic member 438 stretches, it stores energy which is then used to bring about the thigh leg 406 and the rod 410 in alignment, in an entirely

  extended, before setting foot on the ground.

  The ankle joint 412, shown in more detail in FIGS. 16C and 16D, comprises a helical spring 442 placed between the rod 410 and a heel connector 444 attached to the boot,

  preferably at the heel, of the user.

  The ankle joint 412 is intended to cushion the axial shocks and to provide flexibility without hindering the freedom of movement of the user's ankle. The efficiency of the systems according to the present invention can be further improved by adapting several appropriate energy storage mechanisms, such as a spring, an elastic member, or any suitable hydraulic or pneumatic system, and the like, capable of storing at least part of the energy available, when the user's foot is lowered to the ground, and which can reinject at least a portion of the energy stored in the system, so as to reduce the energy requirements of the user, system, or both at once. Figures 17 and 18 and Figure 19 show two examples of these devices, which can be used

  together with the user's shoes.

  Figures 17 and 18 illustrate a spring device which is connected to the sole portion of the user's shoe. Figure 18 shows three spring assemblies. For clarity, only one of these sets is shown in the side view (Figure 17). As best seen in Fig. 18, the spring assembly 200 preferably comprises a first spring 202 and a second spring 204, of different diameters, suitably mounted on an axis of suitable shape 206, connected to the sole of the shoe. The elasticity of the springs and their lengths are such that when the shoe

  approaching the ground, only one of the springs is compressed.

  Another approach to the ground shoe causes the compression of both springs, with greater overall elasticity. In this way, the anti-shock properties of the assembly are increased, the assembly also serving to store released energy

  once the shoe starts to leave the ground.

  Figure 19 illustrates another system for storing usable energy on shoes. The heel of the shoe comprises a special spring 300, of which only the upper and lower spirals are shown in section, and whose turns are connected, respectively, to the shoe and to a movable heel 302. This movable heel 302 is also connected to a hinge pin 304 which pivots on an axis 306 rigidly connected to the shoe,

  near its front end.

  During normal walking, the user first puts his heel on the ground, then advances his foot, when the weight of the user moves forward, so as to place the foot flat on the ground, and then to come into contact with the ground with the anterior end of the foot just before clearing

his foot from the ground.

  The mechanism of Figure 19 takes advantage of

  this sequence of walking to facilitate movement.

  More specifically, the spring 300 normally pushes the movable bead 302 downward. When the heel 302 first contacts the ground, the force exerted between the shoe and the ground compresses the spring, moving the heel 302 towards the shoe (shown in broken lines). As the shoe advances, the spring 300 moves the heel 302 downward, which pivots on the hinge pin 304, the parts of which are still in contact with the ground, so as to produce a slight lift of the shoe from the ground, thus returning a portion of the energy stored to the user to facilitate its operation. Now back to fig. 8 which shows a simplified diagram of a preferred control mode of the apparatus of FIG. 6. The apparatus of fig. 8 includes a CPU 50, of the Intel 80486 type, for example, associated with a plurality of force and torque sensors, also referred to herein as "load sensors", and to a plurality of slave systems. In the illustrated embodiment, the plurality of load cells comprises the following units: a. A load sensor 52 associated with the interface 16, placed between the payload 40 and the frame 14, which intervenes to monitor the forces and the interaction torque between the frame 14 and the payload 40; b. A load sensor 54 associated with the interface 42, placed between the frame 14 and a frame support member, associated with the body, by a belt 56 (Fig. 6), for example. The load sensor 54 intervenes to detect the forces and the interaction couples between

  the human torso and the payload rack 14.

  c. A load sensor 58 associated with the interface 46, placed between the structural member 44 and the user, which intervenes to measure the forces and the interaction couples between the human foot and

said structural member 44.

  d. A load sensor 60 associated with the interface 48, placed between the structural member 44 and the ground. The load sensor 60 intervenes to measure the forces and the interaction couples between the ground and said

structural member 44.

  e. An inertial detection system 62 associated with

the payload 40.

  The load sensors 52, 54, 58, and 60 may each incorporate a force sensor, such as the JR3 multi-axis torque force sensor, sold by JR3, Inc. 22 Harter Ave., Woodland, CA.

95695, USA

  The inertial detection system 62 may comprise three accelerometers arranged to measure accelerations along each of the X, Y, and Z axes. Each accelerometer may, for example, integrate a unit, model 3110, sold by the company EuroSensor, ICSensors, 20 - 24 Kirby St., London EC1N

8TS, UK

  The plurality of servo systems includes the following units: a. A plurality of servo systems 64 including a servo system 64 for each of the joints 24, 27, and 29; and B; a servo system 66 associated with a payload stabilization element 68, as illustrated in FIG.

Fig. 23.

  Each servo-control system 64 may comprise a servo-controlled actuator 80 (FIG 6) controlled by a servo-amplifier which receives feedback information from the servo actuator, via

  speed and position sensors 82 (Fig. 6).

  The slave actuator may, for example, comprise a servo motor, model BMB-045, marketed by Bental Motors, Bental Development Ltd. Kibbutz Merom Golan, 12905, Israel. The servo amplifier may be PWM Mosfet type, sold by Elmo Motion Control Ltd., POB 463, Petah Tikva 49103, Israel. A suitable position sensor may consist of a potentiometer H27-HR-27 (Series H, size 11), marketed by MCB, 48 Avenue Kléber, Courlis I, 92700, Colombes, France. A suitable speed sensor can be represented by a tachometer, marketed by the company Inland Motor

  Division, Kollmorgent Corporation, Radford, VA, USA

  Two methods are now described that can be used by the CPU 50 to control the slave actuators, using the input data

provided by the sensors.

  METHOD 1 comprises the following phases: a. Receive sensor input information to measure the following inputs: 1. FGS = ground-element charge vector

structural (sensor 60).

  2. FUL = frame-belt load vector (sensor 54) 3. FUS = user load vector-structural element (sensor 58) Each load vector comprises three linear force values and three torque values or moments. b. Use conventional impedance control methods to calculate, for each foot, a vector V, as a function of the input torque and input force values above, where: V = desired velocity vector of the structural element one foot, relative to the frame 14. The vector V comprises three linear velocity values and three angular velocity values, corresponding, respectively, to the X, Y, and Z axes. For example, to control the sway of a leg during walking or running, a value is assigned to V to bring the FUS input as close to zero as possible. To control the support of a leg during a relatively slow motion, a value is assigned to V to bring the nearest FUL input

possible from scratch.

  Conventional impedance control methods used in telerobotics are described in the following references, inter alia: 1. Sheridan, T. B., Telerobotics% automation, and human supervisory control, MIT Press, Cambridge,

Massachussetts, USA, 1992.

  2. Hogan, N., "Impedance control: an approach to manipulation: part I theory", Journal of Dynamic Systems, Measurement and Control, 107, pp. 1-7, March 1985; 3. Hogan, N., "Impedance control: an approach to manipulation: part II - implementation", Journal of

  Dynamic Systems, Measurement and Control, 107, pp. 8 -

  16, March 1985; 4. Hogan, N., "Impedance control: an approach to manipulation: part III - applications" Journal of

  Dynamic Systems, Measurement and Control, 107, pp. 17-

24, March 1985.

  5. Kazerooni, H. and Mahoney, S.L. "Strength increase in human-robot interaction", Proceedings of the 1990 American Control Conference, Vol. 3, pp.

  2821-2826, San Diego, CA, USA, 1990.

  6. Strassberg, Y. "A control method for bilateral teleoperating systems", Ph.D. dissertation, Dept. of Mechanical Engineering, University of Toronto,

Canada, 1992.

  c. Receive input information about

  positions and speeds of each joint 24.

  Use conventional inverse dynamics and kinematics techniques to calculate, as a function of the velocity vector V of the desired velocity above, the final outputs which make it possible to obtain this vector. These final outputs comprise the desired angular velocity of each segment or link 22, relative to each adjacent segment 22, which is activated by the speed of the slave actuator 80 associated with each articulation 24. The conventional inverse dynamics and kinematics techniques, used in several robotic applications, are described in the following references, inter alia: 1. Chae, HA et al. "Model based control of a

  robot manipulator ", MIT Press, Cambridge, MA, USA

  1988; 2. Desoer, C. A. and Vidyasagar, M. Feedback Systems: Input-Output Properties, Academic Press, 1975; 3. Leigh, J. R. "Functional analysis and linear control theory", Academic Press, 1980; 4. Spong, M.W., and Vidyasagar, M., "Robot Dynamics and Control" John Wiely and Sons, 1989; 5. Spong, M. W., and Vidyasagar, M. Robust linear compensator design for nonlinear robotic control, IEEE Journal of Robotics and Automation, Vol. RA-3, No. 4, pp. 345-351, 1987; and 6. Vidyasagar, M., "Nonlinear systems

analysis, "Presntice-Hall, 1978.

  METHOD 2 may comprise the following phases: a. Receive sensor input information to measure the following inputs: 1. Sensor 52: torque and frame / payload interaction force; and 2. Sensor 62: inertial speeds and accelerations b. Using the output of the phase a, calculate the relative speed of the payload 40 relative to the frame 14, so that: 1. in the direction of the movement of the human user, the center of mass of the payload 40 remains as far as possible fixed to the human user; 2. in the horizontal direction perpendicular to the movement of the human user, the center of mass of the payload 40, remains in the

as far as possible fixed.

  c. Using the output of phase b, generate commands for the servo system 66 which

  controls the payload stabilizer 68.

  Now back to fig. 6. A particular characteristic of the foot-ground interface element 48 of FIG. 6 is that the latter comprises an elastic element which defines a zone of contact with the ground, along the longitudinal axis determined by the foot, so that a point of zero moment between said elastic member and the ground moves according to the movement of the human user. More specifically, the interface 48 generally intervenes to store energy when the heel of the human user comes into contact with the ground, and to release the energy stored when the toes of the human user

leave the ground.

  The elastic element is preferably configured to have a different rigidity, so that it is relatively low during the contact of the heel, and relatively strong when this

last leaves the ground.

  The foot-ground interface member may, for example, comprise a foot contact member and a ground contact member, in articulation relation with the foot contact member and an elastic member, such as a spring, which is attached to one end of the foot contact member, and at the other end to

ground contact member.

  The apparatus illustrated in Figure 6 preferably comprises a plurality of resilient members, which may incorporate the following elastic members: a. An elastic element 70 (FIG 21) associated with the interface 42, which acts to absorb the forces applying to the human torso. The elastic member is preferably configured to fit a relatively small portion of the human back, so that a relatively large portion thereof,

  and, in particular, the part of the corresponding shoulder, retains its freedom of movement. The elasticity can be provided by springs and / or elastic material, such as elastic foam.

  The elastic member 70 is preferably fixedly associated with the waistband 56. The waistband 56 and the elastic member 70 are preferably removable to the human body. b. An elastic element 72 associated with the interface 46.The elastic element 72 can generally resemble the elastic element 70. The elasticity can be provided by springs and / or an elastic material,

such as an elastic foam.

  c. An elastic element 74 associated with the interface

  48. The elastic member 74 is illustrated in FIG. 19.

  d. An elastic member 90 associated with the interface 16 between the frame 14 and the payload 40, which acts to absorb the interaction forces between the frame and the payload. The elastic element 90 is

illustrated in fig. 20.

  In the embodiment shown, the elastic element 74 is passive, but it will be noted that the latter can, moreover, be active, namely that it can be finally controlled by the CPU 50 of the

Fig. 8.

  The segments 22 are preferably configured to be both lightweight and structurally resistant, and may, for example, have

hollow metal rods.

  The payload stabilization element 68, which is illustrated in FIG. 20, acts to stabilize the payload 40, relative to the human user, so as to prevent the latter from applying forces detrimental to the human user, even when the latter makes lateral movements or flexion, and turnaround movements. Generally, an electronic control unit 84 is provided with the payload 40 and comprises electronic components of the apparatus, such as a CPU 50, an inertial detection system 62, the servo-amplifiers of the servo systems 64 and 66, and a source power

86 (Fig. 8).

  Fig. 20 illustrates the payload 40, the payload stabilizer 68, the elastic member, and the frame 14. As can be seen, the payload 40 includes a container into which articles or loads can be placed. Human user wants to transport from one place to another. The payload 40 is mounted on the payload stabilizer 68 with two degrees of freedom, as

indicated by arrows 92 and 94.

  The payload stabilizer 68 is fixedly mounted on the horizontal portion of the frame 14. The

  stabilizer 68 comprises two vertical parts 95.

  A frame 97, pivotally associated, is preferably driven by a motor 96. The payload 40 is pivotally associated with the frame 97, by two hinges 98, the pivoting movement being preferably provided by a motor 99. The motors 96 and 99 may each include, for example, a direct drive DC torque motor, marketed by Inland Motor, Kollmorgent Corporation, Radford,

VA, 24141.

  The sensor 52 is mounted on the frame 14. Between the sensor 52 and the payload 40 is the element

  elastic 90, which can incorporate a spring.

  Fig. 21 illustrates a detailed side view of the association between the load frame

  useful 40 and the belt 56 of FIG. 6.

  Fig. 22 illustrates an exoskeletal apparatus constructed and operating in accordance with another embodiment of the present invention. The apparatus of FIG. 22 is suitable for

  facilitate the pedaling action of a human user.

  The apparatus of FIG. 22 may be generally similar to the apparatus of FIG. 6. For example, elements 510, 522, 524 and 525 of FIG. 22 may be respectively similar to the elements 10, 22, 24 and 25 of FIG. 6. However, unlike the connector 25 of FIG. 6, the connector 525 of FIG. 22 may have only one degree of freedom,

  know, in the plane of rotation of the pedal 530.

  Although the payload 40 and the corresponding associated elements are omitted in FIG. 22, it will also be noted that the payload 40 and the corresponding associated elements can be mounted together with the apparatus facilitating the pedaling of the

Fig. 22.

  Fig. Figure 23 illustrates the connector 25. As can be seen, the workpiece includes a first hip joint 27 and a second hip joint 29. In the illustrated embodiment, each hip joint has a passive degree of pivotal freedom, as indicated by the arrow 31, and two degrees of freedom of pivoting

  assets as shown by arrows 33 and 35.

  The movement in the direction indicated by the arrow 33 is provided by the motor 37. The movement in the direction

  indicated by the arrow 35 is provided by the motor 39.

  The speed and position information in the three directions indicated by the arrows 31, 33 and, are preferably used in phase c of the

METHOD 1 above.

  An exoskeletal device control apparatus for facilitating the pedaling action is described below with reference to the figures

24 to 28.

  The exoskeletal apparatus according to the present invention is controlled by the movements of the human operator and intended to support the external loads carried by the operator. The device can

  also carry the weight of the operator himself.

  During operation, the human operator is responsible for the stability of the apparatus and controls the desired directions of movement. The apparatus provides the operator with all the degrees of spatial freedom required to manage the control of the device, and occurs only when the system addresses critical conditions that may threaten stability.

of it.

  The conditions under which the device operates can be divided into three categories, the first two defining the term "critical": 1) a region of global instability, 2) a region in which the device is responsible for maintaining its stability 3) a region in which the operator is responsible for maintaining stability

* overall system.

  The control system of the present invention preferably performs the following tasks: a) controlling the interaction between the operator and the apparatus, and between the apparatus and the environment; (b) allow the operator to control, control and stabilize the apparatus; c) provide overall stability, including key state variables that the operator can not control; (d) monitor performance standards in

conditions of uncertainty.

  Referring now to the schematic vector illustration of FIG. 24, it should be noted that the control system according to the present invention

  is based on impedance control principles.

  These principles were first published by Hogan N. in "Impedance Control: An Approach to Manipulation: Part III - Applications," Journal of Dynamic Systems, Measurement and Control, Vol. 107

March 1985, pp. 17 to 24.

  The operator applies a force Fh to the apparatus. This force Fh is measured by a force sensor 500 which produces an output signal Fh ', which is converted by the desired impedance model 502 into a required speed signal Vc. Vc is the speed at the point of application of the force. The Jacobian (J) of the system, which is the ideal approximated algorithm, converts the required velocity signal into a generalized velocity signal qc, which represents velocity in a common coordinate system. The generalized speed signal qc is transmitted to the servo speed loop 504, which outputs the actual common speeds q. By multiplying q by the inverse Jacobian, we calculate the actual velocity at the point

  of the operator-device interaction.

  To simplify the operation of the system, we will adopt ideal values for all elements of the schematic illustration, o: Fh = Fh 'q = qc and

J = J '.

  Fig. 25 represents this ideal situation.

  Theoretically, the system of fig. 25 is able to control the impedance, or the interaction, between the operator and the apparatus, and to achieve the desired performance values. The higher the desired impedance values, the higher the speed values obtained by the apparatus, using lower forces, Fh. The control system thus allows the operator to control the speed V of the apparatus, by applying the force Fh, using the desired impedance model. In an ideal situation, the higher the desired impedance value. is high, the less the operator-apparatus interaction exists, and as forces or moments develop between the operator and the apparatus, the velocity V will increase and tend to reduce the interactive forces Fh. A device "mastered" by its operator is thus created. In practice, it is not possible to achieve an ideal system, and interactive forces will develop, mainly because of the dynamic interaction between the device and the terrain. The control system is intended for

reduce these forces to a minimum.

  Referring now to FIG. 26 the operation of the control system and its components will now be examined. Fig. Figure 26 illustrates the procedure of the apparatus, mounted this time, on a shaping bicycle as opposed to a person. The overall stability effect is thereby eliminated because the apparatus is supported by a structure

  fixed, which facilitates the examination of components.

  The human operator remains at the controls, and the burden of

  the device is provided by the load mechanism of the bicycle. The operation of the apparatus, mounted on the shaping bicycle, will now be described in detail.

  The mechanical system preferably comprises three degrees of freedom, including two active degrees, and is driven by closed-loop servo activators, and a passive degree of freedom. The configuration of these degrees, as shown in FIG. 26, takes into account the following considerations: 1. Kinematic similarity with the biomechanical structure of the human leg. From the simple point of view of kinematics, a single degree of freedom

  would be enough to propel the pedals of the bicycle.

  However, to approximate the structure of the bicycle to the structure of the human leg, which can be considered as having three main degrees of freedom, namely, the thigh, knee, and ankle, a three

  degrees of freedom to perform the experiment.

  2. Adequacy with walking experiments: A three-degree configuration, kinematically adapted to the human leg, is also suitable for walking experiments, in which a fourth degree of freedom, representing the transverse stability of walking,

is not necessary.

  The mechanical structure of the bicycle is indicated by reference numeral 598. Two force gauges 600 and 602 are placed on each side of an arm 604, which represents the passive degree of freedom. The gauge 600 measures the force produced by the operator-apparatus interaction, and the gauge 602 measures the force generated by the apparatus and the pedal of the bicycle 606. The control of the apparatus by the operator is possible, thanks to the information output of these two gauges, whose signals materialize external forces * applied to the device. The pedal of the bicycle 606 is fixed by means of a mechanical arm 608 to the axis of the pedal 610. It is at this point that the charging moment, the direction of which is always opposite to the direction of the rotation vector (indicated

by arrow 612) is measured.

  The control system consists of two main loops: an internal speed loop, based on the torque calculation technique, and an external force loop, based on the impedance control method. This configuration makes it possible to control

  the device, even under critical conditions.

  Fig. 27 schematically shows the

  elements used in the bicycle experience.

  The human operator, represented by the block 700, applies a force, while riding the bicycle, on the footrests of the apparatus. FhR is a vector

  of the force applied by the operator on the

  702 right feet, and FhL is a vector of the force applied by the operator on the left footrest 704. The FhR and FhL vectors are measured by two force gauges, whose outputs are respectively FhR 'and FhL' . The forces applied by the human operator are also applied to the servo actuators of the device. In this form, the FhR and FhL forces are converted by the JTR and JTL Jacobians into ThR and ThL load moments, which operate in the joints of the aircraft. The interactive FPR and FPL forces are measured simultaneously between the pedal and the footrest, respectively, on the right and left sides. The output signals from the gages, respectively, 706 and 708, are multiplied by force increase coefficients, 710 and 712, respectively, and the results of the multiplication are used to calculate the applied total forces ZFR and EFL, respectively. , right and left footrest. The EFR and EFL forces are converted using the desired impedance model 714, at the desired footrest speeds VRC and VLC. This conversion operation also takes into account the state measurements of the pedals of the bicycle, to exclude unnecessary speed components, such as components intervening in a direction that do not contribute to the

real speed.

  The desired velocities VRC and VLC are converted by the Jacobian models J'R and J'L into desired velocity values, qRC and qLC, in the common axes. These values are output on the servo loops, respectively, 716 and 718, which produce, respectively, the actual common speeds, qR and qL. The outermost loop of the control system, shown in fig. 27, is

  finally closed by the human operator.

  The speed loops will now be described with reference to FIG. 28. Speed loops fulfill three essential roles: 1. controlling speeds (controlling the output of the desired speeds by the impedance controller); 2. ensure reliability in the face of uncertainties in system parameters;

3. decouple the control.

  Speed loop control is based on modeled control algorithms, the most important of which are described by Chae et al. in "Model

  Based Control of a Robot Manipulator ", MIT Press, 1988.

  In the case of the bicycle experience, a CTT (torque calculation technique) is more appropriate. Firstly, and knowing the real model of the controlled system, all the linear and non-linear coupling elements of the model are eliminated. The velocity loop is then closed based on the assumption that no I0 element exists in the coupling system. Indeed, it is impossible to eliminate all the coupling elements of the

  model, since the real model is unknown.

  The following parameters are defined with reference to the schematic illustration of FIG. 28: n = number of degrees of freedom Fex = external force qs Rn = generalized coordinates M (q) s Rnxn = inertia matrix hs Rn = gravity forces, centripetal and Coriolis UE Rn = command, with dimensions of generalized forces Fex Es Rn = vector of external forces j E Rnxn = Jacobian matrix of the apparatus Ud s Rn = interferences, and N <= represents the Cartesian spatial dimension N <= 6 o: M (q) q '' + h (q , q ') = U + JTFex + Ud is an equation that serves as a model for the apparatus of the present invention, representing the motion of a body, having n degrees of freedom, and interacting with an external force Fex . Annex A is a Fortran list of a software application of a portion of the apparatus of FIG. 22. Annex A is a software simulation of an exoskeleton useful for facilitating stationary pedaling. Biomechanical considerations useful for designing an exoskeletal device and facilitating walking, running and transporting actions of a patient.

  payload, are going to be exposed now.

  In general, the man-machine system can be divided into three phases: double support, when both legs are in contact with the ground; simple support, when one leg supports, but not the other; and sustenance, when there is no

contact with the ground.

  Phase detection can be based on the outputs of the force sensors installed in the

machine-ground interfaces (22).

  During double support, the control is responsible for reducing the error between the reference dynamic forces (desired) and measured at the interfaces of the machine with the man, the ground and the payload. Dynamic servoing of the machine to the human operator can be maintained, therefore, by imposing speed control on the machine's actuators in a manner that decreases the error between the reference dynamic forces and

  measured at the interfaces of the machine.

  During simple support and lift, the control functions in the same way as during dual support; the difference is in the adjustment of the reference levels for the desired interface force / dynamics values: these phases (ie simple support and lift) differ from the dual support, in the sense that one or both legs are not in contact with each other. floor. The force applied, and thus measured, at the interface 22 of a moving leg (in motion = not in contact with the ground) is equal to zero or very close to zero. To maintain the desired correspondence between kinematics of moving legs of the operator and the machine, the (desired) reference force at the interface 182 of a

  Moving leg is set to zero.

  In the case of simple support, the reference level settings at the interfaces 22 and 182 of the moving leg are therefore set to zero, and those of the reference levels at the interfaces 22 and 182 of the support leg, as well as references to interfaces 181 and 20 are set to the desired dynamic force values, calculated in the manner

previously described.

  During the lift phase of the pace, all reference levels are set to zero, since during the lift phase each of the elements of the system moves in space as a free body. When the human operator moves segments of his body relative to each other, the machine follows this movement by controlling the actuators to bring all the forces of interfaces

  to their zero reference values.

  The control logic described above is not generally based on the sequencing of the phases of pace, because it depends solely on the detection of these, namely, whether each leg is in contact with the ground, or not , and not on the sequencing, namely the order of appearance of the different phases. This is considered an advantage since it allows the controller to monitor the system successfully in situations that may not be classified as "normal pace". For example, the same control scheme satisfactorily treats the transition task from standing to kneeling, and vice versa, from kneeling position I0 to standing. When the operator begins to bend his knees and ankles, to lower his trunk vertically, the forces exerted on the human-machine interface, in the trunk-pelvis region (interface 181), increase above their reference value, thereby increasing, above its reference level, the difference between the forces measured at the interface 22 and at the interface 182; the control logic immediately imposes speed commands to the actuators of the machine to reduce these errors, resulting in the kneeling action of the latter which follows completely the movement

  kneeling of the human operator.

  It is known that the features shown and described herein, in the context of separate embodiments, may be provided in all possible combinations and that, on the contrary, each illustrated and described embodiment which includes several features may, moreover, be presented with a single feature, or only

some of these features.

  It is known to those skilled in the art that the present invention is not limited to what has been specifically described and shown above. More precisely, the scope of this

  invention is limited only by the claims

that follow:

Claims (5)

  A foot-ground interface member comprising: an elastic member defining an area of contact with the ground along the horizontal axis defined by the foot, such that a point of zero moment between the elastic member and the soil moves according to the movement of the human user.   The foot-ground interface member according to claim 1, which acts to store energy when the heel of the human user makes contact with the ground, and to release the stored energy when the   toes of the human user leave the ground.   A foot-ground interface member comprising: an elastic member configured to have a different rigidity such that rigidity is relatively low during heel contact and relatively high when last leaves the ground.   4. Foot-ground interface member comprising: - a foot contact member; - a ground contact member in articulation relation with the foot contact member; and - an elastic member attached to one end of the foot contact member and at the other end of the limb member. ground contact.   Apparatus according to claim 4, wherein   the elastic member comprises a spring.