CN110215358B - Electric wheelchair with autonomous stair climbing function and control method thereof - Google Patents

Electric wheelchair with autonomous stair climbing function and control method thereof Download PDF

Info

Publication number
CN110215358B
CN110215358B CN201910617317.2A CN201910617317A CN110215358B CN 110215358 B CN110215358 B CN 110215358B CN 201910617317 A CN201910617317 A CN 201910617317A CN 110215358 B CN110215358 B CN 110215358B
Authority
CN
China
Prior art keywords
wheelchair
shaft
driving motor
stair climbing
center
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910617317.2A
Other languages
Chinese (zh)
Other versions
CN110215358A (en
Inventor
洪日
张鹤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jilin University
Original Assignee
Jilin University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jilin University filed Critical Jilin University
Priority to CN201910617317.2A priority Critical patent/CN110215358B/en
Publication of CN110215358A publication Critical patent/CN110215358A/en
Application granted granted Critical
Publication of CN110215358B publication Critical patent/CN110215358B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
    • A61G5/00—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs
    • A61G5/06—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
    • A61G5/00—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs
    • A61G5/06—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
    • A61G5/061—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps for climbing stairs
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
    • A61G5/00—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs
    • A61G5/06—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
    • A61G5/063—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps with eccentrically mounted wheels
    • A61G5/065—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps with eccentrically mounted wheels with three or more wheels mounted on a rotary cross member, e.g. spiders or spoked wheels with small wheels at the end of the spokes
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
    • A61G2203/00—General characteristics of devices
    • A61G2203/10—General characteristics of devices characterised by specific control means, e.g. for adjustment or steering
    • A61G2203/22—General characteristics of devices characterised by specific control means, e.g. for adjustment or steering for automatically guiding movable devices, e.g. stretchers or wheelchairs in a hospital

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Handcart (AREA)

Abstract

The invention discloses an electric wheelchair with an autonomous stair climbing function, which comprises: a wheelchair frame; the driving motors are symmetrically and fixedly arranged on two sides of the wheelchair frame respectively; one end of each driving shaft is fixedly connected with an output shaft of the driving motor; a plurality of travel mechanisms, comprising: a traveling mechanism mounting bracket rotatably supported at the other end of the driving shaft; a plurality of travel wheels rotatably mounted on the travel mechanism mounting frame; a plurality of first sprockets rotatably mounted on the running gear mounting frame; wherein, the center shaft of the first sprocket is fixedly connected with the center of the travelling wheel; a chain surrounding the plurality of first sprockets; a plurality of second sprockets disposed outside the chain; the first chain wheel and the second chain wheel are respectively meshed and driven by the chain; a sun gear fixedly mounted on the drive shaft; a plurality of planetary gears meshed with the sun gear; wherein, the center pin of planet wheel and the center fixed connection of second sprocket.

Description

Electric wheelchair with autonomous stair climbing function and control method thereof
Technical Field
The invention belongs to the technical field of electric wheelchairs, and particularly relates to an electric wheelchair with an autonomous stair climbing function and a control method thereof.
Background
With the improvement of the living standard of people and the aggravation of the aging phenomenon of society, and the acceleration of the living rhythm of people, the products for helping the old and the elderly gradually become the pets in the market. However, many old people today have advanced in age, and the old people are inconvenient to travel due to diseases or degradation of body organ functions, so that the spirit and physical state of the old people may be further deteriorated. This phenomenon is more serious for the elderly living in the building without elevators, and the process of going up and down the stairs is an absolute gap for the weak elderly to isolate them from the outside. Even if someone assists the old to go upstairs and downstairs, the whole process is time-consuming and labor-consuming, and better experience cannot be obtained.
At present, more electric wheelchairs exist in the market, and the electric wheelchairs mainly increase the driving force of electric wheels for common wheelchairs, so that users can operate the wheelchairs to move on flat and better roads by themselves. However, when facing complex environments such as stairs, the wheelchair is unable to function. There is also a wheelchair with a crawler-type travelling mechanism on the back on the market, which can meet the function of transporting users in a stair environment, but needs to be controlled and operated by others, and the user cannot independently control and operate, so that the wheelchair is essentially a cargo transportation machine, and has higher physical quality requirements on operators and higher labor intensity.
Disclosure of Invention
The invention provides an electric wheelchair with an autonomous stair climbing function, which aims to realize the functions of automatically walking and stair climbing of the wheelchair under the condition of no assistance of others through the cooperation transmission of a chain wheel and a planetary gear train.
The invention provides a control method of an electric wheelchair with an autonomous stair climbing function, which is used for controlling the output torque ratio of a front shaft driving motor and a rear shaft driving motor of the wheelchair according to the inclination angle of the wheelchair so as to ensure that the wheelchair climbs a slope without revolution of a planet carrier and ensure the comfort of the wheelchair to the greatest extent.
The technical scheme provided by the invention is as follows:
an electric wheelchair with an autonomous stair climbing function, comprising:
A wheelchair frame;
the driving motors are symmetrically and fixedly arranged on two sides of the wheelchair frame respectively;
One end of each driving shaft is fixedly connected with the output shaft of the driving motor;
a plurality of traveling mechanisms respectively installed at the other ends of the driving shafts;
The power supply is fixedly arranged on the wheelchair frame and is used for supplying power to the driving motor;
Wherein, the travel mechanism includes:
A travel mechanism mount rotatably supported on the drive shaft;
A plurality of travel wheels rotatably mounted on the travel mechanism mount and evenly distributed about the drive shaft;
A plurality of first sprockets rotatably mounted on the travel mechanism mount;
Wherein, the center shaft of the first sprocket is fixedly connected with the center of the travelling wheel;
A chain surrounding the plurality of first sprockets;
a plurality of second sprockets disposed outside the chain and between two adjacent first sprockets;
wherein the first sprocket and the second sprocket are respectively meshed with the chain for transmission;
a sun gear fixedly mounted on the drive shaft;
A plurality of planetary gears meshed with the sun gear;
the center shaft of the planet wheel is fixedly connected with the center of the second chain wheel.
Preferably, a hollow shaft is fixedly connected to the center of the travelling mechanism mounting frame, and the hollow shaft is sleeved on the driving shaft through a bearing.
Preferably, the electric wheelchair with the autonomous stair climbing function further comprises: the fixed baffles are arranged on the wheelchair frame, and shaft sleeves are fixedly arranged on the fixed baffles respectively;
the fixed baffles are arranged in one-to-one correspondence with the advancing mechanisms, and the hollow shafts are arranged in the shaft sleeve in a matching manner.
Preferably, the driving motor is integrated with a reduction gearbox.
Preferably, the electric wheelchair with the autonomous stair climbing function further comprises: and the driving motor controller is arranged on the wheelchair frame and used for controlling the driving motor.
Preferably, the electric wheelchair with the autonomous stair climbing function further comprises:
The control handle is arranged on the armrest of the wheelchair and is connected with the driving motor controller through a circuit;
The safety switch is arranged on the lower side of the handrail and is connected with the driving motor controller through a circuit; and
And the angle sensor is fixedly arranged on the wheelchair frame and is electrically connected with the driving motor controller.
Preferably, the travel mechanism is four;
Wherein two traveling mechanisms are respectively arranged on two sides of the wheelchair frame; and the advancing mechanisms positioned at the two sides of the wheelchair frame are respectively and symmetrically arranged.
The control method of the electric wheelchair with the autonomous stair climbing function is used for controlling the electric wheelchair with the autonomous stair climbing function, and when climbing a slope, the control method is used for controlling the ratio of the output torque of a driving motor at the front part of the wheelchair to the output torque of a driving motor at the rear part of the wheelchair to be as follows:
Wherein, The inclination angle of the wheelchair relative to the horizontal direction is H, and the height of the mass center of the wheelchair when the wheelchair is horizontally placed; l is the distance between the front drive shaft of the wheelchair and the rear drive shaft of the wheelchair; b is the distance between the center of mass in the horizontal direction and the axis of the rear drive shaft of the wheelchair when the wheelchair is placed horizontally.
Preferably, when climbing stairs, the ratio of the output torque of the driving motor at the front part of the wheelchair to the output torque of the driving motor at the rear part of the wheelchair is controlled as follows:
Wherein,
In the method, in the process of the invention,For a prescribed time, the maximum value of the inclination angle of the inner wheel chair relative to the horizontal direction,The minimum value of the inclination angle of the inner wheel chair relative to the horizontal direction is set for a prescribed time.
Preferably, when the wheelchair starts on a level ground, the ratio of the output torque of the drive motor at the front part of the wheelchair to the output torque of the drive motor at the rear part of the wheelchair is controlled to be:
Wherein d is the diameter of the travelling wheel, and L is the distance between the front driving shaft of the wheelchair and the rear driving shaft of the wheelchair; h is the height of the mass center when the wheelchair is horizontally placed; r c is the distance between the center of the travelling wheel and the center of the driving shaft, i g is the transmission ratio between the sun wheel and the planet wheel; i s is the gear ratio between the second sprocket and the first sprocket.
The beneficial effects of the invention are as follows:
(1) The electric wheelchair with the autonomous stair climbing function provided by the invention realizes the functions of automatically walking and stair climbing of the wheelchair under the condition of no assistance of other people through the matched transmission of the chain wheel and the planetary gear train.
(2) According to the control method of the electric wheelchair with the autonomous stair climbing function, provided by the invention, the output torque ratio of the front shaft driving motor and the rear shaft driving motor of the wheelchair is controlled according to the inclination angle of the wheelchair, so that the wheelchair can climb a slope without revolution of the planet carrier, and the comfort of the wheelchair can be ensured to the greatest extent.
(3) According to the control method of the electric wheelchair with the autonomous stair climbing function, when the wheelchair starts on the flat ground, the output torque ratio of the front shaft driving motor and the rear shaft driving motor of the wheelchair is controlled, so that the wheelchair can start to advance at the maximum acceleration under the condition that the planet carrier does not revolve, the torque of the motor can be fully utilized, and the power performance of the wheelchair is improved.
Drawings
Fig. 1 is a schematic diagram of the overall structure of an electric wheelchair with an autonomous stair climbing function.
Fig. 2 is a schematic rear view of the electric wheelchair with an autonomous stair climbing function according to the present invention.
Fig. 3 is a schematic structural view of a travelling mechanism according to the present invention.
Fig. 4 is a schematic diagram of a connection relationship between a sprocket set and a traveling wheel according to the present invention.
Fig. 5 is a schematic diagram of a planetary gear train according to the present invention.
Fig. 6 is a schematic diagram of the radius of gyration of the travelling wheel axis around the center of the planetary gear system when the planet carrier revolves.
Detailed Description
The present invention is described in further detail below with reference to the drawings to enable those skilled in the art to practice the invention by referring to the description.
As shown in fig. 1-2, the present invention provides an electric wheelchair with an autonomous stair climbing function, which mainly comprises: the wheelchair frame 110, two armrests 120, a seat cushion 130, four drive motors 140, four drive shafts 150, four travel mechanisms 160, and a power source 170.
The two armrests 120 are symmetrically and fixedly disposed on the left and right sides of the wheelchair frame 110. The seat cushion 130 is fixedly mounted above the wheelchair frame 110 and disposed between the two armrests 120.
Four driving motors 140 are symmetrically installed at two sides of the lower portion of the wheelchair frame 110 in pairs, a reduction gearbox is integrated on the driving motors 140, and power output is performed after the reduction gearbox is used for reducing the speed. In the present embodiment, the front and rear parts of the wheelchair frame 110 are fixedly provided with motor mounting plates 111, respectively, the motor mounting plates 111 are vertically disposed, and the driving motors 140 are fixedly mounted on the motor mounting plates 111, respectively, through motor frames 141. The four driving shafts 150 are arranged in one-to-one correspondence with the driving motors 140; wherein, one end of the driving shaft 150 is fixedly connected with the output shaft of the driving motor 140, and the other end is installed with a traveling mechanism 160. A power source 170 is fixedly installed at the front of the wheelchair frame 110 for powering the four drive motors 140.
As shown in fig. 3, the traveling mechanism 160 includes: a travel mechanism mount 161, a plurality of travel wheels 162, a sprocket set 163, and a planetary gear set 164.
To fit the travel mechanism, four fixed baffles 112 are provided on the wheelchair frame 110, the fixed baffles 112 being vertically disposed between each drive shaft 150 and the travel mechanism 160; a sleeve 113 is fixedly installed on each of the fixing shutters 112.
A hollow shaft 161a is fixedly connected to the center of the inner side (side facing the wheelchair frame 110) of the travel mechanism mounting frame 161, the hollow shaft 161a is arranged in the shaft sleeve 113 in a matching manner, and the hollow shaft 161a can freely rotate in the shaft sleeve 113. Meanwhile, the hollow shaft 161a is internally provided with a bearing, and is matched and arranged on the driving shaft 150 through the bearing, so that the driving shaft can freely rotate relative to the hollow shaft 161 a. A plurality of traveling wheels 162 are rotatably installed at the outer side (the side far from the wheelchair frame 110) of the traveling mechanism mounting frame 161, and the plurality of traveling wheels 162 are uniformly distributed around the driving shaft 150. In the present embodiment, the number of the traveling wheels 162 is 3.
As shown in fig. 4, the sprocket set 163 is provided inside the traveling wheels 162 (toward one side of the wheelchair frame 110), and the sprocket set 163 includes a plurality of first sprockets 163a, the number of first sprockets 163a being the same as the number of traveling wheels 162. The first sprocket 163a is rotatably mounted on the traveling mechanism mount 161; and the center shaft of the first sprocket 163a is fixedly connected with the center of the traveling wheel 162 so that the traveling wheel 162 can rotate synchronously with the first sprocket 163 a. A chain 163b surrounding the plurality of first sprockets 163 a; a plurality of second sprockets 163c disposed outside the chain 163b and located at a center position of the chain 163b between two adjacent first sprockets 163 a. The first sprocket 163a and the second sprocket 163c are engaged with the inside and outside of the chain 163b, respectively. In the present embodiment, the number of the second sprockets 163c is 3.
As shown in fig. 5, a planetary gear train 164 is provided inside the sprocket set 163 (toward one side of the wheelchair frame 110), and the planetary gear train 164 includes a sun gear 164a and a plurality of planetary gears 164b. Sun gear 164a is coaxially fixedly mounted on drive shaft 150; a plurality of planet gears 164b are disposed about the sun gear and in meshing drive with the sun gear 164 a; the center shaft of the planetary gear 164b is fixedly connected with the center of the second sprocket 163c, and the second sprocket 163c rotates synchronously with the planetary gear 164b.
The drive shaft 150 transmits power to the sun gear 164a in the planetary train on both sides when the travel mechanism is in operation. When traveling on the flat ground, the sun gear 164a transmits power to the planet gears 164b, and then drives the second chain wheel 163c to rotate, so that the chain 163b is driven to move, and the chain 163b drives the first chain wheel 163a to rotate; the first sprocket 163a rotates to drive the traveling wheel 162 to rotate forward. When the stairs are climbed or the road surface gradient is large, the travelling wheel 162 positioned at the front part of the wheelchair frame 110 is locked by the obstacle, so that the sprocket set 163 and the middle planetary wheel 164b of the planetary wheel train 164 cannot rotate, the planetary wheel 164b is approximately rigidly connected with the sun wheel 164a, and the sun wheel 164a directly drives the planetary wheel train to revolve and climb over the obstacle.
In this embodiment, the power supply 170 is a lithium battery; and the lithium battery used in this example is a conventional battery, and will not be further described herein.
In this embodiment, the electric wheelchair with the autonomous stair climbing function further includes a hand push handle 180, where the hand push handle 180 is fixedly connected to the wheelchair frame 110.
In another embodiment, the electric wheelchair with an autonomous stair climbing function further includes: a drive motor controller (not shown), a control handle 190, a safety switch (not shown), and an angle sensor (not shown). The driving motor controller is installed on the wheelchair frame 110 for controlling four driving motors 140; the functions of forward rotation, reverse rotation, stopping rotation, slow start, speed regulation and the like of the driving motor 140 can be realized through the driving motor controller. The control handle 190 is mounted on the right hand armrest of the wheelchair and is connected to the drive motor controller by an electrical circuit. The safety switch is installed at the lower side of the handrail and is connected with the driving motor controller through a circuit, and outputs a signal when the pressure above the handrail is smaller than a set value, so that the driving motor 140 is stopped slowly. The angle sensor is fixedly installed on the wheelchair frame 110 and electrically connected with the driving motor controller, for measuring an inclination angle of the wheelchair (an inclination angle between a traveling direction of the wheelchair and a horizontal plane). The driving motor controller receives signals from the safety switch, the operating handle 190 and the angle sensor at the same time, and respectively controls parameters such as rotation speed, steering and the like of the four driving motors 140 to achieve different driving intentions. The travelling speed of the wheelchair can be controlled by controlling the rotating speed of the driving motor, and the steering of the wheelchair can be controlled by controlling the rotating speed difference of the driving motors at the left side and the right side of the wheelchair. By controlling the output characteristics of the front shaft and the rear shaft of the wheelchair, the wheelchair can be assisted to work better on a road surface with gradient. The driving motor controller also has a slow start function, so that the motor torque is prevented from being too large in the starting process.
The electric wheelchair with the autonomous stair climbing function has the working principle that: in operation, power is transmitted from the output shaft of the drive motor 140 via the drive shaft 150 to the sun gear 164a of the planetary gear set in the planetary gear train, where the planetary gear train 164 has two degrees of freedom in rotation of the planet gears 164b and revolution of the planet carrier (equivalent to the travelling wheel travelling mechanism mount 161), and the revolution torque of the planet carrier depends only on the output torque of the drive motor 140. The planetary gear train 164 has two operating states, a flat ground travel state and a stair climbing state. When traveling on the flat ground, the driving motor 140 outputs a small torque, and the rotation (revolution) of the carrier is restrained by the gravity of the wheelchair itself, so that only the remaining planetary gears 164b rotate by one degree of freedom. The planetary gear 164b rotates to drive the second sprocket 163c coaxially connected, and the power is transmitted to the first sprocket 163a through the chain 163b, thereby driving the traveling wheel 162 to rotate and driving the wheelchair to travel. When the travelling wheel 162 at the front part of the wheelchair hits an obstacle when the climbing stairs or the gradient is large, the travelling wheel cannot rotate, and the planetary wheel 164b cannot rotate due to the chain 163 b; the motor output torque increases, so that the revolution torque of the planet carrier in the planetary gear train 164 increases, and when the revolution torque is greater than the constraint caused by the self weight of the wheelchair, the planet carrier starts to revolve, thereby driving the traveling wheel 164 to revolve around the axis of the driving shaft 150, climb over the step, and start to climb the stairs.
The invention also provides a control method of the electric wheelchair with the autonomous stair climbing function, which is used for controlling the electric wheelchair with the autonomous stair climbing function, and when the wheelchair climbs a slope, the output torque ratio of the front shaft driving motor and the rear shaft driving motor of the wheelchair is controlled according to the inclination angle of the wheelchair, so that the wheelchair is ensured to climb the slope under the condition that the planet carrier does not revolve, and the comfort of the wheelchair can be ensured to the greatest extent.
When the wheelchair runs on a flat road at a constant speed, the revolution torque of the planet carrier is small, the gravity revolution of the wheelchair cannot be overcome, the planet wheels in the planet wheel train rotate, and the travelling wheels are driven to rotate through the chains to drive the wheelchair to advance. At this time, the forward speed v of the wheelchair is:
Wherein n is the rotation speed of an output shaft of the driving motor; i g is the transmission ratio of the planetary gear system; i s is the sprocket set transmission ratio; d is the diameter of the travelling wheel.
The tendency for revolution due to the carrier increases as the running wheel resistance (motor output torque) increases. The revolution of the planet carrier can lead to the wheelchair to be fluctuated continuously, and the use experience is affected. In order to improve the comfort of the wheelchair, the wheelchair needs to be controlled to climb a slope in a flat running state (running wheel rotation state) as much as possible until the inclination angle of the wheelchair (corresponding to the road surface inclination angle) exceeds the maximum slope angle through which the wheelchair can pass in the flat running state (running wheel rotation state)In this case, the stair climbing state (the carrier revolution state) is switched.
On a sloping road, the influence of the road inclination angle on the road pressure at the front and rear axles (drive axles) of the wheelchair is:
Wherein, F A is the normal pressure of the ground to the front axle, which is the inclination angle of the wheelchair in the horizontal direction; f B is the normal pressure of the ground against the rear axle; h is the height of the mass center when the wheelchair is horizontally placed; l is the distance between the front axle and the rear axle of the wheelchair; b is the distance between the center of mass and the axis of the rear axle in the horizontal direction when the rear axle is horizontally placed; g is the total gravity of the wheelchair during operation.
The preparation method comprises the following steps of:
When the front and rear shaft planetary carriers are in a limit state before revolution, the relationship between the motor torque and the normal pressure of the corresponding shaft is as follows:
Wherein M A1、MA2 is the torque of the driving motor at the left side and the right side of the front shaft respectively; m B1、MB2 is the torque of the driving motor at the left side and the right side of the rear axle respectively; r c is the radius of revolution of the travelling wheel axis around the centre of the planetary gear train when the planet carrier revolves, i.e. the distance between the travelling wheel centre axis and the drive shaft centre axis (as shown in figure 6).
If the inclination of the wheelchair in the horizontal direction is knownThe limit torque of the front and rear shaft motor at the current angle can be calculated under the condition that the planet carrier does not revolve.
When the driving force F t is equal to the sliding force of the extended slopeAt the time of the equilibrium, the balance,Reaching the maximum value
The preparation method comprises the following steps of:
in summary, under the condition that the wheelchair climbs a slope, after the sensor measures that the wheelchair has a larger inclination angle, the front and rear shaft motors are cooperatively controlled, so that the output torque ratio of the driving motor of the front shaft of the wheelchair to the driving motor of the rear shaft of the wheelchair is as follows:
The torque of the motor can be fully utilized, so that the inclination angle of the wheelchair on the ground is not more than While traveling in a flat ground traveling state.
The stair climbing working condition is similar to the control method of the climbing working condition, and in the stair climbing working condition, in order to ensure that the planetary gear trains run efficiently, the front and rear shaft planetary gear trains do not interfere, and the ratio s f of the output torque of the front and rear shaft driving motor in stair climbing is required to be controlled. The value of s f is the same as the calculation method of s under the climbing working condition, and is the ratio of the ground to the front and rear axle method phase pressure, namely:
Wherein, The average value of the maximum inclination angle and the minimum inclination angle of the inner wheel chair relative to the horizontal direction for a period of time; i.e.
Wherein, For a maximum value of the inclination of the wheelchair relative to the horizontal recorded by the sensor over a period of time,The minimum value of the inclination of the wheelchair relative to the horizontal recorded by the sensor over a period of time.
Due to the inclination angle of the wheelchair in the horizontal direction when climbing stairsIn real time, fluctuation along with stairs, thus measuring in real timeThe value cannot be used for calculation, so the average value of the inclination angles of the wheelchair and the horizontal direction in a period of time is takenAnd calculating to obtain a front and rear shaft torque distribution coefficient s f when the ladder is climbed, so as to control the front and rear shaft driving motor.
In another embodiment, when the wheelchair starts on the flat ground, the output torque ratio of the front axle driving motor and the rear axle driving motor of the wheelchair is controlled to ensure that the wheelchair starts to advance with the maximum acceleration under the condition that the planet carrier does not revolve, so that the torque of the motor can be fully utilized, and the power performance of the wheelchair is improved.
When the road surface inclination angle is 0, the planetary carrier is not revolved and is driven only by the rotation of the travelling wheel, and the output torque of the driving motor is required to be limited; in order to achieve larger acceleration, the motor torques of the front and rear shafts need to be reasonably distributed.
When the wheelchair runs forward in an acceleration way by the acceleration a, the normal pressure relation between the front and rear axles and the ground is as follows:
wherein m 0 is the total mass of the wheelchair during operation.
The relation between the acceleration a and the driving torque of the driving motor is:
When the front and rear shaft planetary carriers are in a limit state before revolution, the relationship between the motor torque and the normal pressure of the corresponding shaft is as follows:
The finished brought-in can be used in critical cases:
in summary, under the starting working condition of the flat ground traveling state, the output torque ratio of the front axle driving motor and the rear axle driving motor of the wheelchair is cooperatively controlled to be:
The motor torque can be fully utilized, and the wheelchair can start and advance at the maximum acceleration a max under the condition that the planet carrier does not revolve. Wherein a max is:
In addition, in order to ensure the use safety, when the wheelchair goes downstairs, the front shaft motor is driven, the rear shaft motor is braked slightly, so that the moment for overturning the wheelchair backwards is provided, and the wheelchair is prevented from turning down the stairs forwards.
Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.

Claims (8)

1. An electric wheelchair with an autonomous stair climbing function, comprising:
A wheelchair frame;
the driving motors are symmetrically and fixedly arranged on two sides of the wheelchair frame respectively;
One end of each driving shaft is fixedly connected with the output shaft of the driving motor;
a plurality of traveling mechanisms respectively installed at the other ends of the driving shafts;
The power supply is fixedly arranged on the wheelchair frame and is used for supplying power to the driving motor;
Wherein, the travel mechanism includes:
A travel mechanism mount rotatably supported on the drive shaft;
A plurality of travel wheels rotatably mounted on the travel mechanism mount and evenly distributed about the drive shaft;
A plurality of first sprockets rotatably mounted on the travel mechanism mount;
Wherein, the center shaft of the first sprocket is fixedly connected with the center of the travelling wheel;
A chain surrounding the plurality of first sprockets;
a plurality of second sprockets disposed outside the chain and between two adjacent first sprockets;
wherein the first sprocket and the second sprocket are respectively meshed with the chain for transmission;
a sun gear fixedly mounted on the drive shaft;
A plurality of planetary gears meshed with the sun gear;
The center shaft of the planet wheel is fixedly connected with the center of the second chain wheel;
The number of the travelling mechanisms is four;
Wherein two traveling mechanisms are respectively arranged on two sides of the wheelchair frame; the travelling mechanisms positioned at the two sides of the wheelchair frame are respectively and symmetrically arranged;
The control method of the electric wheelchair with the autonomous stair climbing function comprises the following steps:
when climbing a slope, the ratio of the output torque of the driving motor at the front part of the wheelchair to the output torque of the driving motor at the rear part of the wheelchair is controlled as follows:
Wherein, The inclination angle of the wheelchair relative to the horizontal direction is H, and the height of the mass center of the wheelchair when the wheelchair is horizontally placed; l is the distance between the front drive shaft of the wheelchair and the rear drive shaft of the wheelchair; b is the distance between the center of mass in the horizontal direction and the axis of the rear drive shaft of the wheelchair when the wheelchair is placed horizontally.
2. The electric wheelchair with the autonomous stair climbing function according to claim 1, wherein a hollow shaft is fixedly connected to the center of the travelling mechanism mounting frame, and the hollow shaft is sleeved on the driving shaft through a bearing.
3. The electric wheelchair with an autonomous stair climbing function according to claim 2, further comprising: the fixed baffles are arranged on the wheelchair frame, and shaft sleeves are fixedly arranged on the fixed baffles respectively;
the fixed baffles are arranged in one-to-one correspondence with the advancing mechanisms, and the hollow shafts are arranged in the shaft sleeve in a matching manner.
4. An electric wheelchair with autonomous stair climbing function according to any one of claims 1-3, wherein the drive motor is integrated with a reduction gearbox.
5. The electric wheelchair with an autonomous stair climbing function according to claim 4, further comprising: and the driving motor controller is arranged on the wheelchair frame and used for controlling the driving motor.
6. The electric wheelchair with an autonomous stair climbing function according to claim 5, further comprising:
The control handle is arranged on the armrest of the wheelchair and is connected with the driving motor controller through a circuit;
The safety switch is arranged on the lower side of the handrail and is connected with the driving motor controller through a circuit; and
And the angle sensor is fixedly arranged on the wheelchair frame and is electrically connected with the driving motor controller.
7. The electric wheelchair with an autonomous stair climbing function according to claim 6, wherein the control method of the electric wheelchair with an autonomous stair climbing function further comprises:
When climbing stairs, the ratio of the output torque of the driving motor at the front part of the wheelchair to the output torque of the driving motor at the rear part of the wheelchair is controlled as follows:
Wherein,
In the method, in the process of the invention,For a prescribed time, the maximum value of the inclination angle of the inner wheel chair relative to the horizontal direction,The minimum value of the inclination angle of the inner wheel chair relative to the horizontal direction is set for a prescribed time.
8. The electric wheelchair with an autonomous stair climbing function according to claim 7, wherein the control method of the electric wheelchair with an autonomous stair climbing function further comprises:
when the wheelchair starts on the parallel ground, the ratio of the output torque of the driving motor at the front part of the wheelchair to the output torque of the driving motor at the rear part of the wheelchair is controlled as follows:
Wherein d is the diameter of the travelling wheel, and L is the distance between the front driving shaft of the wheelchair and the rear driving shaft of the wheelchair; h is the height of the mass center when the wheelchair is horizontally placed; r c is the distance between the center of the travelling wheel and the center of the driving shaft, i g is the transmission ratio between the sun wheel and the planet wheel; i s is the gear ratio between the second sprocket and the first sprocket.
CN201910617317.2A 2019-07-10 2019-07-10 Electric wheelchair with autonomous stair climbing function and control method thereof Active CN110215358B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910617317.2A CN110215358B (en) 2019-07-10 2019-07-10 Electric wheelchair with autonomous stair climbing function and control method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910617317.2A CN110215358B (en) 2019-07-10 2019-07-10 Electric wheelchair with autonomous stair climbing function and control method thereof

Publications (2)

Publication Number Publication Date
CN110215358A CN110215358A (en) 2019-09-10
CN110215358B true CN110215358B (en) 2024-09-17

Family

ID=67812944

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910617317.2A Active CN110215358B (en) 2019-07-10 2019-07-10 Electric wheelchair with autonomous stair climbing function and control method thereof

Country Status (1)

Country Link
CN (1) CN110215358B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110525534A (en) * 2019-09-27 2019-12-03 吉林大学 A kind of small vehicle chassis structure and its control method using complicated landform
CN110606136B (en) * 2019-10-22 2023-12-29 吉林大学 A logistics robot with omnidirectional movement and obstacle-crossing capabilities and its control method
GB2589892A (en) * 2019-12-11 2021-06-16 Penny & Giles Controls Ltd Protection apparatus and method for an electric wheelchair
FR3155704A1 (en) * 2023-11-28 2025-05-30 Stellantis Auto Sas MOTOR VEHICLE FOR CROSSING OBSTACLES
CN117838451B (en) * 2024-03-07 2024-05-07 广东工业大学 A device for assisting disabled people to go up and down stairs

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105857359A (en) * 2016-05-06 2016-08-17 吉林大学 A multifunctional power-assisted carrying device
CN108210189A (en) * 2018-03-01 2018-06-29 贾银霞 One kind electric boosted can walk and climb building driving device
CN210521234U (en) * 2019-07-10 2020-05-15 吉林大学 An electric wheelchair with autonomous stair climbing function

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3827607A1 (en) * 1987-09-03 1989-03-16 Dieter Dipl Ing Henkes Stair-climbing wheel-chair
CN2209099Y (en) * 1994-08-08 1995-10-04 熊家伟 Climbing wheel
US5632499A (en) * 1995-06-06 1997-05-27 Gtmax, Inc. Wheel chair system
US20100032911A1 (en) * 2006-03-06 2010-02-11 Sterraclimb Llc Stair-Climbing Wheeled Vehicle
CN201052225Y (en) * 2006-12-22 2008-04-30 杜丁丁 Electric wheelchair up/down stair device
CN102319154B (en) * 2011-08-16 2013-05-01 上海电机学院 Stair climbing wheel chair
CN104887417B (en) * 2015-06-16 2018-05-08 北京理工大学 A kind of wheel footpath size adjustable mechanism suitable for electric wheelchair
CN104921881A (en) * 2015-07-11 2015-09-23 贵州大学 Novel electric stair climbing wheelchair chassis and design method thereof
CN108056873A (en) * 2017-12-27 2018-05-22 东莞市天合机电开发有限公司 A kind of sick bed with turn over aid

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105857359A (en) * 2016-05-06 2016-08-17 吉林大学 A multifunctional power-assisted carrying device
CN108210189A (en) * 2018-03-01 2018-06-29 贾银霞 One kind electric boosted can walk and climb building driving device
CN210521234U (en) * 2019-07-10 2020-05-15 吉林大学 An electric wheelchair with autonomous stair climbing function

Also Published As

Publication number Publication date
CN110215358A (en) 2019-09-10

Similar Documents

Publication Publication Date Title
CN110215358B (en) Electric wheelchair with autonomous stair climbing function and control method thereof
US4790548A (en) Climbing and descending vehicle
TWI677331B (en) Electric assisted walking and climbing drive device
US4044850A (en) Wheelchair
CA2863971C (en) Step-climbing attachment for a wheeled chair
CN101897641B (en) Dual-purpose travel-aided device for flat ground and stairs
US3231290A (en) Wheel chair for regular and irregular surface travel
WO2009069144A2 (en) Methods and systems for ascending and descending stairs
CN105559984B (en) One kind nursing assisting system
CN102319154A (en) Stair climbing wheel chair
JP2002264856A (en) Stair climbing device
CN202641747U (en) Motor-driven electrical power assisted stair climbing cart
CN106882321B (en) Multi-purpose electric bicycle of body-building of riding instead of walk
CN110279528B (en) Open wheel type electric stair climbing vehicle and operation method thereof
CN111870441B (en) A front-suspension crawler stair climbing power-assisted vehicle
CN212281925U (en) Battery-assisted walking and stair climbing multifunctional wheelchair
KR102307658B1 (en) Auxiliary power unit for manual wheelchair
CN210521234U (en) An electric wheelchair with autonomous stair climbing function
CN111317622A (en) Multifunctional wheelchair with storage battery for assisting in walking and climbing stairs
CN205515253U (en) Building wheelchair is climbed to two tracks of single section based on swing of walking wheel
CN111096861A (en) Self-adaptive electric wheelchair capable of climbing steep slope
CN106985952B (en) Multi-purpose electric bicycle of body-building of riding instead of walk
JP2008154840A (en) Stair-climbing electric wheelchair
CN215535761U (en) Novel wheelchair-assisted stair climbing device
TWM576451U (en) Electric power assisted walking and stair climbing driving device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant