WO2017153382A1

WO2017153382A1 - Rolling walker with support function and method for controlling same

Info

Publication number: WO2017153382A1
Application number: PCT/EP2017/055280
Authority: WO
Inventors: Steffen Walther
Original assignee: Kuka Roboter Gmbh
Priority date: 2016-03-10
Filing date: 2017-03-07
Publication date: 2017-09-14
Also published as: DE102016203972A1

Abstract

The invention relates to a method for controlling a mobility assistance system, such as particularly a rolling walker, with a motorised drive. The method comprises the detection of a force acting on the assistance system and/or a tilting movement of the assistance system. It is then determined whether a slipping threshold value relating to slipping of the assistance system is exceeded. It is then determined whether a tilting threshold value relating to tilting of the assistance system is exceeded. If the slipping threshold value or the tilting threshold value is exceeded, a control of the drive is carried out.

Description

ROLLATOR WITH SUPPORT FUNCTION AND METHOD FOR CONTROLLING THE SAME

l. Technical part

The present invention relates to a method for controlling a

Mobility assistance system, in particular a rollator, as well as a mobility assistance system with motorized drive.

2. Technical background

A mobility assistance system is a system which, for example, can increase the mobility of a person with reduced mobility. Such a system may be, for example, a rouler that can assist a person's walking. Furthermore, a wheelchair can be considered as a mobility assistance system, since this also the mobility of a

People raised.

However, a mobility assistance system can also be used to move objects. Thus, for example, a shopping cart can be understood as a mobility assistance system with which the mobility of the operator is increased insofar as the movement of heavier objects is supported by the mobility assistance system.

Such assistance systems are often used inside, such as

for example in apartments. However, such systems can also be used outdoors to increase the range of motion of the person to be supported.

A mobility assistance system, such as a RoUator, can serve as a solid or stable support for the operator. The stability can be achieved by a vertical load on the handles. In order to provide a good supporting function, especially at a standstill, many roilators with equipped with a kind of parking brake. With this, the wheels of the rollator are braked so that the RoUator does not move away when an operator, for example, leans against the RoUator. But if now high

Transverse loads acting on the RoUator, for example in the form of a horizontal force on the handles, can lead to a tilting or slipping of the rollator and associated heavy falls of the person to be supported.

Many roilators have a relatively low dead weight of 5-10 kg, so that, in particular in the case of poor stiction, the case may arise where the roUator can slip away even when the wheels are locked. Once such a slide has occurred, the movement of the rollator is thus dominated by sliding friction instead of static friction, this condition can be difficult to be discharged again. Even with a force of about 20 N, which acts horizontally on the handles, the RoUator can tilt over the blocked wheels. This can occur, for example, when a seated person wants to pull himself on the RoUator in the state. Likewise, the RoUator can easily tip over or skid when a person is leaning against it laterally. Such slipping or tipping can lead to falls or uncontrolled movements of the person to be supported.

It is therefore an object of the present invention to provide a mobility assistance system which at least partially eliminates the above-mentioned disadvantages. In particular, it is an object of the present invention to provide a method for controlling a mobility assistance system with which a secure support of a person is made possible.

These and other objects, which will become apparent from the following description, are achieved, at least in part, by a method for controlling a mobility assistance system according to claim 1 and by a mobility assistance system according to claim 17. 3. Content of the invention

The present invention relates to a method for controlling a

Mobility assistance system. Such a mobility assistance system can be used, in particular, to assist the walking of elderly or movement-restricted people, as a transport system (eg shopping carts) or even to

Rehabilitation measures are used after surgery. A user can cling to the assistance system for this purpose and control it accordingly in order to go in a desired direction.

In particular, the assistance system is preferably a rollator. The assistance system may have a plurality of wheels, which may be at least partially omni-directionally movable.

The mobility assistance system has a motorized drive. For this purpose, the assistance system can have a drive unit which is set up to drive at least one wheel of the assistance system. By means of the motorized drive can thus the movement of the to be supported

People are further supported, since in particular the weight of the assistance system can be compensated thereby, so that the assistance system can be easily pushed by the user. In this case, the drive can also compensate for the inertia of the assistance system when accelerating and / or decelerating when cornering and, for example, the slope output force when walking on a gradient. However, these applications are only exemplary in nature.

The motorized drive may include software, electronics and mechanics, and convert a control signal into a corresponding propulsion of the driven wheel. The wheel is preferably driven electrically.

For this purpose, an energy store (such as a battery) may preferably be provided on the assistance system in order to supply the drive with the required energy. To control the assistance system, appropriate sensors can be provided on the handles of the assistance system in order to be able to detect desired movements as user input and to convert these into corresponding control signals for the motorized drive. The method comprises detecting a force acting on the mobility assistance system and / or a tilting movement of the

Assistance system. It can be determined, for example, that a force acts on the assistance system, resulting for example from a support of an operator on the assistance system. This force can be detected, for example, by means of force sensors. The detected tilting movement of the assistance system can also result from this force acting on the assistance system and be detected, for example, by inclination sensors.

In principle, different means or methods can be used to detect a force acting on the assistance system or a tilting movement of the assistance system. The direction and amplitude need not be determined for this purpose, it may be sufficient in particular to detect that, for example, a force of more than 10 N acts.

The method further includes determining if a skid limit for slipping the assistance system has been exceeded. For this purpose, the previously detected force is used or considered. This slip limit value can be a predefined slip limit value and be determined during the installation, assembly or installation of the mobility assistance system. For example, the slip limit may correspond to an acting force of 10N. Actual slippage does not yet have to occur, so that the slip limit value can, for example, be an acting force

which corresponds to 80% of the actually required force for a slide.

Furthermore, the method comprises determining whether a tipping limit for a tipping of the assistance system is exceeded. For this purpose, the previously detected force and / or the previously detected tilting movement is used or considered. The tilt limit can also be set during installation,

Installation or device of the assistance system has been established.

Again, there is no need to actually overturn the assistance system when the tilt limit is reached. Rather, the tipping limit can be defined with sufficient safety distance to the actual tipping limit. The person skilled in the art understands that slipping and tilting typically do not have to occur simultaneously. Slippage can occur, for example, when a force in the direction of travel acts on the rollator while the wheels are locked. Tipping can occur, in particular, when a force acting transversely to the direction of travel acts on an elevated position of the assistance system. Whether the slip or tilt limit is exceeded, can thus take place in particular taking into account the structure, the construction and the center of gravity of the assistance system.

Further, the method includes driving the drive in response to determining that the skid limit or the skip limit is exceeded to counteract tilting or slipping of the assistance system. It is thus initiated an evasive movement, to ultimately reduce the risk of tipping or slipping. For example, if a force acts in a certain direction and the slip limit is exceeded, the assistance system can be controlled by driving the drive in the direction of

Drive force effect, thus preventing the threat of slipping. This resulting movement does not necessarily have to be exactly in the direction of the force effect. By controlling the tilting movement of the rollator can be stopped. Preferably, the method further includes, prior to driving the drive, a stalling of the assistance system, and the driving of the drive preferably comprises a release of the stalling brake. It can thus

For example, first a function can be activated (for example, by a manual user input), which the parking brakes of the

Assistance system activated so that the assistance system acts as a solid support. If a user is now supported on the device, for example, the device may slip or tilt. To perform the evasive movement to counteract this tilting or slipping of the assistance system, the parking brake is preferably first loosened or loosened and then or simultaneously the drive is driven. Preferably, the slip limit is a predefined slip limit. This is preferably based on the weight of the assistance system. Furthermore, at least approximately, the support force of the operator can be taken into account. Further, the slip limit is preferably based on a coefficient of friction, which is particularly preferably defined for vinyl, laminate, wood or parquet floors. The person skilled in the art will understand that the friction coefficient can be defined as a measure of the friction force in relation to the contact force between two bodies. Of the

Friction coefficient can be determined in particular depending on the material of the tires of the assistance system. Depending on the location of the

Assistance system, such as in retirement homes, the

Coefficient of friction can be defined for the corresponding soil conditions. If the location of the assistance system different

Ground conditions, it is the expert to define the slip limit with respect to the soil with the worst detention characteristics to guarantee the safest possible use of the assistance system.

The tilting limit value is preferably a predefined tilting limit value, which is in particular a maximum tilting of the assistance system relative to the horizontal plane of i ° -45 °, in particular preferably 2 ° -30 °, more preferably 3 ° -20 °, and further preferably 5 ° -io ° corresponds. The skilled person understands, depending on the application of the assistance system, to select suitable tilting limits. These may e.g. be determined by simple experiments. Preferably, the assistance system has a tilt of o ° when it is on a plane without a slope, and no lateral force acts.

The slip and tilt limit can be stored in a database, the structure, the construction, the center of gravity o.ä. of

Assistance system considered. Thus, from the database

appropriate values are taken to the detected force or

Check tilting movement. Preferably, the predefined tilt limit value describes the maximum tilt of the assistance system during a standstill of the

Assistance system. Thus, after reaching the stop of the

Assistance system determined the current position of the assistance system as the initial value, and the eventual subsequent tilting of the

Evaluate assistance system against the rest position. In particular, when driving on a slope may therefore be an unwanted

Evasive movement caused by the slope are prevented.

Preferably, the drive of the drive is such that the

Assistance system performs a movement of i-ιοο cm, more preferably 2-50 cm and more preferably 5-20 cm. Thus, only one local, i. low, evasive movement designed to reduce the risk of slipping or tipping. Particularly preferably, a stalling of the assistance system takes place following the movement. Thus, the operator can continue to rest on the assistance system without falling. If now again the slip or tilt limit is exceeded, a further evasive movement can be initiated. Preferably, the movement can be stopped as soon as the tilt limit and slip limit are met again. The detection of the force acting on the assistance system preferably takes place by means of motor current measurements. For this purpose, in particular the currents can be evaluated, which are present in the motorized drive, for example, for stalling the assistance system. By measuring the

Motor current can be applied to the drive wheels and thus to the

Drive units acting forces are detected.

Preferably, the force acting on the assistance system is detected by means of a force sensor. This force sensor is preferably arranged above the center of gravity of the assistance system, and in particular assigned to a handle of the assistance system. For example, 2-D or 3-D force sensors can be used to apply to the

Rollator or acting on the assistance system force to detect. Also Force and / or torque sensors that work by means of strain gauges can be used for this purpose. Force sensors associated with the handles can also be used in particular for detecting the movement of the rollator desired by the operator. In particular, it is preferable to determine whether the slip limit value or the tilting limit value has been exceeded by using the vertical position of the force sensor on the assistance system. Thus, in particular, the lever arm can be taken into account, which can support the unwanted tilting of the assistance system. Preferably, detecting the force acting on the assistance system comprises determining the direction and magnitude of the force. Thus, not only the amplitude of the force can be determined, but also the

Direction in which the force acts. Preferably, then, it is determined whether the skid limit or the dump limit is exceeded using the determined direction and magnitude of the force. Depending on the structure of the assistance system can thus be distinguished precisely whether slipping or tipping threatens. Furthermore, the resulting driving of the drive can also be done using the determined direction of force or force magnitude, so that the risk of tipping and slipping is reduced efficiently.

Preferably, the detection of the tilting movement of the assistance system takes place by means of a position sensor. Thus, the position or inclination of the

Assistance system with respect to the horizontal plane, for example by means of 2D tilt sensors are detected. Preferably, the force acting on the assistance system is detected by means of spring deflection measurement in the wheel suspension of the assistance system. This can also be deduced the contact force to the ground. For example, sensors in the wheel suspensions

evaluated and thus as error-free as possible impending tilting can be detected. Preferably, the force acting on the assistance system is detected by means of a force sensor in the chassis of the assistance system. In this way, in particular, the braking force can be evaluated in a stalled assistance system. Corresponding force sensors can also be used for other functions, for example, to increase ride comfort by intelligent control of the drive.

Preferably, the drive is controlled such that the

Assistance system actively moves at least partially in the direction of the acting force. As a result, in particular, the acting force can be reduced, so that the risk of slipping or tilting is reduced.

Preferably, the driving of the drive is performed in such a way that the force acting on the assistance system is reduced. This applies in particular to the case of possible slippage, since moving the assistance system causes the force which acts on the assistance system and a

Slippage can be reduced.

Preferably, the drive of the drive is such that the

Assistance system responsive to the acting force responds. In particular, the control of the assistance system can in particular preferably flexibly regulate the assistance system in the direction of the overload or force effect, for example by means of force regulation.

In order to counteract the tilting of the assistance system, the driving of the drive can preferably take place taking into account the instantaneous position or inclination of the assistance system. In this case, due to the resulting movement, the position or inclination can be reduced by the drive system, e.g. in the direction of the occurred inclination of the

Assistance system is moved.

Furthermore, the invention relates to a mobility assistance system with a motorized drive. The assistance system has means for

Detecting a force acting on the assistance system and / or a Tilting movement of the assistance system. Furthermore, the assistance system comprises means for driving the drive. Furthermore, the assistance system comprises a controller which is set up to carry out a method described above for controlling the mobility assistance system, in particular to counteract a tilting or slipping of the assistance system. For this purpose, the controller can be set up in particular to determine whether a slip limit or tilt limit is exceeded, as described above. The controller does not have to be a single component at the same time

Assistance system may be provided, but may be distributed to various modules that may be at least partially provided on the assistance system.

4th embodiments

In the following, the present invention will be described in detail with reference to the accompanying drawings. 1 shows a mobility assistance system according to an embodiment; and

2 schematically shows the sequence of a method for controlling a mobility assistance system according to a further embodiment.

FIG. 1 shows a mobility assistance system 1, which is designed in the form of a rollator 1. The rollator 1 generally comprises a frame and a plurality of wheels 12, 19. Although only two wheels are shown, the skilled person understands that a mobility assistance system can have any number of wheels. Preferably, three or four wheels are used, of which at least one can be actively driven. A user can rest on a handle 13 of the rollator 1 and push the rollator 1 in a desired direction.

The rollator 1 of Fig. 1 further comprises a motorized drive 11, with which at least the front wheel 12 can be actively moved. To detect and perform desired movements is between the Handle 13 and the frame of the rollator 1, a force sensor 14 is provided which can detect the forces acting on the handle 13 forces. For example, it can thus be recognized that the operator would like to push the rollator 1 forward. Based on the detected forces of the motorized drive 11 is driven to perform the desired movement of the rollator 1. For this purpose, in particular, a control 15 is provided, which with both the force sensor 14 and the drive 11 in

Communication can stand. The drive 11 may further with a

Energy storage 16 may be connected, which may be formed, for example in the form of a battery or a battery. Preferably, the

Energy storage 16 provided such that the center of gravity of the rollator 1 as low as possible. As a result, the risk of tipping can already be significantly reduced.

The rear wheel 19 of the rollator 1 is connected via a normal suspension 18 to the frame 10. The rear wheel 19 is thus passive, and is not actively driven by the motorized drive 11. Alternatively, the rear wheels, or all wheels, are driven. A drive of the rear wheels is particularly advantageous because in this case the front wheels can be designed as freely rotatable, passive castors. In addition, this has the advantage that the force on the rear wheels is higher due to the supporting force by the user, as in the front wheels and thus the

Drive wheels have more contact pressure. In the suspension 18 damping elements or a suspension may be provided, wherein the

Deflection of the suspension can be provided to the controller 15. Further, a mechanical parking brake 17 is provided on the rear wheel 19, which can brake the rear wheel 19 firmly. Such a brake may also be provided on a driven wheel.

To brak the rollator 1, the drive 11 can be controlled accordingly, so that a movement of the wheel 12 is actively counteracted. Also, by activating the mechanical parking brake 17, the rear wheel 19 can be braked. Activating the electrical Parking brake function via the drive 11 or the mechanical parking brake 17 can be done via the controller 15.

Furthermore, an inclination or position sensor 10 is provided on the frame of the RoUators 1. By means of this, the inclination of the RoUators 1 can be determined with respect to the horizontal. The controller 15 can in

Communication with the position sensor 10 stand to obtain and evaluate the slope values.

FIG. 2 schematically illustrates a flowchart illustrating the steps of a method for controlling a mobility assistance system according to an embodiment of the present invention. This scheme will be described below with reference to the rollator 1 of FIG. 1. The steps may be at least partially by the

Control 15 of the RoUators 1 are performed.

The method begins with step 21, in which the rollator 1 is braked. For this purpose, the motorized drive 11 can be controlled accordingly or the parking brake 17 can be activated. As a result, the rollator 1 is fixed so that an operator can lean on it.

In step 22, a force acting on the rollator 1 is detected. This can be done in various ways: For example, by means of the force sensor 14, a force acting on the handle 13 force can be detected. Further, the motor currents present in the motorized drive 11 can be evaluated to finally detect a force acting on the rollator force. Also performing a suspension travel measurement in the rear

Wheel suspension 18 can be used to at least back on a force acting on the rollator 1 force and thus to detect them.

In step 23, a tilting movement of the assistance system is detected. This can be done for example by means of the position sensor 10, which is accommodated on the frame of the RoUators 1. On the tilting movement of the RoUators 1 but also by analyzing the suspension travel in the suspension getting closed. Also torque sensors, which may be mounted in the force sensor 14, for example, can be used for this purpose.

In step 24, it is determined whether a slip limit for slippage of the assistance system has been exceeded. This determination takes place under

Use of the force detected in step 22. The slip limit value can be stored as a predefined slip limit in the controller 15 of the rollator 1. This slip limit gives an upper limit for the maximum allowable force, which may act on the rollator 1. Of the

Slip limit does not have the actual limit between

Stiction and sliding friction or sliding friction describe, but may, for example, already at 80% of the maximum possible adhesive force.

In step 25, it is determined whether a tilting limit for tilting of the rollator 1 has been exceeded. This determination is made using the force detected in step 22 and / or using the tilting motion detected in step 23. For example, it can be stated here that the tilting movement has exceeded a predefined tilting limit value of 15 ⁰ , for example. The predefined tilt limit does not have to describe the actual limit for tilting, for example, the tilting can occur only at 20 ⁰ . The determination of the step 25 can take into account the position of the force sensor 14, so as to be able to conclude a possible lever arm.

If the check in step 24 or 25 is negative, the method in step 22 is continued. If the test in step 24 or 25 is positive, ie, there is a risk of slipping or tilting, the drive 11 is activated in step 26 in order to counteract a tilting or slipping of the assistance system 1. For this purpose, in particular the stalling of the wheels can be reduced or solved. As a result of the movement of the rollator 1, the force acting on the rollator 1 can ultimately be reduced. After performing this evasive movement is again in step 27, a stalling of the rollator 1, so that the operator is now on the

fixed rollator 1 can support and not in consequence of Evasive movement crashes. As a result, at least a heavy fall of the operator and the high risk of injury by a tilting RoUator l is minimized. Subsequently, the method is continued in step 22.

LIST OF REFERENCE NUMBERS

1 RoUator

10 tilt sensor

11 motorized drive

12 front wheel

13 handle

14 force sensor

15 control

16 energy storage

17 Parking brake

18 suspension

19 rear wheel

Claims

claims

A method of controlling a mobility assistance system (1), in particular a rollator (1), with motorized drive (s), comprising:

Detecting a force acting on the assistance system (1) and / or a tilting movement of the assistance system (1);

Determine, using the detected force, whether a

Slip limit for slippage of the assistance system (l) is exceeded;

Determining, using the detected force and / or using the detected tilting movement, whether a tilt limit for tilting of the assistance system (1) has been exceeded; and

Driving the drive (s) in response to detecting that the skid limit or the skip limit is exceeded to counteract tilting or slippage of the assistance system (1).

2. The method of claim l, further comprising, prior to driving the drive (s), a stalling of the assistance system, and wherein the driving of the drive (s) includes a release of the stall brake.

3. The method of claim 1 or 2, wherein the slip limit is a predefined slip limit, which is based on the weight of the assistance system (1) and a coefficient of friction, the coefficient of friction preferably for vinyl, laminate, wood or

Parquet floor is defined.

4. The method according to any one of claims 1-3, wherein the Kippgrenzwert is a predefined Kippgrenzwert which maximum tilt of the assistance system (1) relative to the horizontal plane of i ° -45 °, preferably from 2 ° -30 °, more preferably from 3 ° -20 ° and more preferably from 5 ⁰ - io ° corresponds.

5. The method of claim 4, wherein the predefined tipping limit value describes the maximum tilt of the assistance system (1) during a standstill of the assistance system (1).

6. The method according to any one of claims 1-5, wherein the driving of the drive (11) takes place such that the assistance system (1) a movement of 1-100 cm, preferably 2-50 cm and more preferably from 5-20 cm performs.

7. The method of claim 6, wherein after the movement, a stalling of the assistance system (1).

8. The method according to any one of claims 1-7, wherein the detection of the force acting on the assistance system (1) force by means of motor current measurement.

9. The method according to any one of claims 1-8, wherein the detection of the force acting on the assistance system (1) force by means of a force sensor (14), which is arranged above the center of gravity of the assistance system (1) and in particular a handle (13) of the Assistance system (1) is assigned.

10. The method of claim 9, wherein the determining whether the

Slip limit or the Kippgrenzwert is exceeded, using the vertical position of the force sensor (14) on the assistance system (1).

11. A method according to any one of claims 1-10, wherein detecting the force acting on the assistance system (1) comprises determining the direction and magnitude of the force, and determining whether the

Slip limit or the Kippgrenzwert is exceeded, and preferably also the driving of the drive (11) using the determined direction and magnitude of the force done.

12. The method according to any one of claims 1-11, wherein the detection of the tilting movement by means of a position sensor (10) and / or means

Spring travel measurement in the suspension (18) of the assistance system (1).

13. The method according to any one of claims 1-12, wherein the detection of the force acting on the assistance system (1) force by means of a force sensor in the chassis of the assistance system (1).

14. The method according to any one of claims 1-13, wherein the driving of the drive (11) takes place such that the assistance system (1) actively moves in the direction of the acting force.

15. The method according to any one of claims 1-14, wherein the driving of the drive takes place in such a way that the force acting on the assistance system (1) is reduced.

16. The method according to any one of claims 1-15, wherein the driving of the drive takes place in such a way that the assistance system (1) reacts yielding to the acting force.

17. Mobility assistance system (1), in particular a rollator (1), with motorized drive (11), comprising:

Means (10, 11, 14, 15, 18) for detecting an on the

Assistance system (1) acting force and / or a tilting movement of the assistance system (1);

Means for driving the drive (11); and

a controller (15) arranged to perform a method according to any of claims 1-16 for controlling the assistance system (1).