CN108839015A - A kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition methods - Google Patents
A kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition methods Download PDFInfo
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- CN108839015A CN108839015A CN201810558891.0A CN201810558891A CN108839015A CN 108839015 A CN108839015 A CN 108839015A CN 201810558891 A CN201810558891 A CN 201810558891A CN 108839015 A CN108839015 A CN 108839015A
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- wheel
- motion
- robot
- bobbin movement
- obstacle detouring
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/16—Programme controls
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/16—Programme controls
- B25J9/1656—Programme controls characterised by programming, planning systems for manipulators
- B25J9/1664—Programme controls characterised by programming, planning systems for manipulators characterised by motion, path, trajectory planning
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D1/00—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot
- G05D1/02—Control of position or course in two dimensions
Abstract
The invention discloses a kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition methods, include the following steps：1) rotary state of each rotating wheel is obtained；2) obstacle detouring bobbin movement model is established, determines position p of the trolley entirety mass center O point on two axles centre distance D (t)o；3) p in bobbin movement is calculatedoThe velocity magnitude V at placeOWith path P (t)；4) dolly chassis path function and yaw angle function are established, the coordinates of motion of mass center are calculated；5) it is established according to the coordinates of motion of step 4), brings the rotary state of each rotating wheel into, export the motion profile of trolley.Robot obstacle detouring bobbin movement track provided by the invention acquisition methods; it is not only suitable for axis connection chassis; it is suitable for spring connecting base plate again, is capable of the acquirement of real-time implementation robot motion position feedback and motion path, to helps to realize robot motion's navigation and motion conditions description.
Description
Technical field
The present invention relates to automation control areas, more particularly to a kind of robot two-wheel differential obstacle detouring bobbin movement track
Acquisition methods.
Background technique
In the prior art, robot generally use two-wheel it is differential come realize movement, i.e., two driving wheels are respectively connected with solely
Vertical driving motor, current obstacle detouring chassis is mainly stiff shaft connecting base plate, since the connection type of rigid axis connection to transport
Without motion is free in vertical direction for driving wheel, therefore its chassis obstacle performance is poor, cannot travel on the road surface for having hollow, by force
Degree is higher, and suppleness is poor, and solving this problem is to reduce chassis rigidity, but this chassis is not using spring connecting base plate
It is easy accurate control, can not determine its motion conditions during exercise, in the prior art, it is differential more to lack a kind of robot two-wheel
Hinder bobbin movement track acquisition methods, makes it that can either be applied to axis connection chassis, while can also apply to spring chassis.
Summary of the invention
In view of the above drawbacks of the prior art, technical problem to be solved by the invention is to provide a kind of robot two-wheels
Differential obstacle detouring bobbin movement track acquisition methods make it that can either be applied to axis connection chassis, while can also apply to spring
Chassis.
To achieve the above object, the present invention provides a kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition sides
Method includes the following steps：
1) rotary state of each rotating wheel is obtained；
2) obstacle detouring bobbin movement model is established, determines trolley entirety mass center O point on two axles centre distance D (t)
Position；
3) p in bobbin movement is calculatedoThe velocity magnitude V at placeOWith path P (t)；
4) dolly chassis path function and yaw angle function are established, the coordinates of motion of mass center are calculated；
5) it is established according to the coordinates of motion of step 4), brings the rotary state of each rotating wheel into, export the motion profile of trolley.
It preferably, is p according to mapping position of the following formula counting of carriers mass center O point on D (t) in the step 2)o
Place：
D=2 (Rk+Rd)
D be two wheelbases of trolley when static and horizontal from；
RdFor fixed point above spring and driving wheel centre distance；
RkFor spring lower fixing point and center chassis distance.
Preferably, in the step 3), p in bobbin movement is calculated according to the following formulaoThe velocity magnitude V at placeOAnd path P
(t)：
Wherein, R is driving wheel radius；
RdFor fixed point above spring and wheel centre distance；
RkFor spring lower fixing point and center chassis distance；
θdlFor revolver axis and x-axis angle；
θdrFor right wheel axis and x-axis angle；
θwlFor the crank degree of revolver；
θwrFor the crank degree of right wheel；
For the rotational angular velocity of revolver；
For the rotational angular velocity of right wheel；
Preferably, in the step 3), simplify calculate p according to the following formulaoThe velocity magnitude V at placeOWith path P (t)：
Movement can be approximately considered θ on general two-dimensional surfacedl=θdr；poIt is approximately equal to 2 (Rk+Rd)；It can simplify
(2-3) determines that new center of mass motion formula is：
Preferably, in the step 4), include the following steps：
41) it is as follows to establish yaw angle function：
41)
42) θ is calculated according to the following formuladl, θdr：
Wherein, l0For the initial length of spring；
K is the coefficient of elasticity of spring；
M is trolley quality；
G is acceleration of gravity；
L is the length of spring,
43) counting of carriers chassis path function according to the following formula, obtains the coordinates of motion O (x, y) (t) of mass center；
Wherein, θwlIt (t) is t moment revolver rotational angle；
θwrIt (t) is t moment right wheel rotational angle.
The beneficial effects of the invention are as follows：Robot obstacle detouring bobbin movement track provided by the invention acquisition methods, were both applicable in
In axis connection chassis, and it is suitable for spring connecting base plate, is capable of real-time implementation robot motion position feedback and motion path
It obtains, to help to realize robot motion's navigation and motion conditions description.
Detailed description of the invention
Fig. 1 is the flow chart of the embodiment of the invention.
Fig. 2 is stress analysis schematic diagram of the invention.
Fig. 3 is kinematics analysis figure of the present invention to chassis.
Fig. 4 is the chassis structure figure of embodiment of the present invention.
Fig. 5 is the front view of Fig. 2.
Fig. 6 is the verifying flow chart the present invention is based on spring connecting base plate.
Fig. 7 is the analogue system figure of the embodiment of the present invention.
Fig. 8 is the simulation experiment result figure of the present invention.
Fig. 9 is that chassis output trajectory and actual observation trajectory diagram are surveyed in the embodiment of the present invention.
Specific embodiment
Present invention will be further explained below with reference to the attached drawings and examples：
As shown in Figure 1, a kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition methods, include the following steps：
1) rotary state of each rotating wheel is obtained；
2) obstacle detouring bobbin movement model is established, determines trolley entirety mass center O point on two axles centre distance D (t)
Mapping position is po；
3) p in bobbin movement is calculatedoThe velocity magnitude V at placeOWith path P (t)；
4) dolly chassis path function and yaw angle function are established, the coordinates of motion of mass center are calculated；
5) it is established according to the coordinates of motion of step 4), brings the rotary state of each rotating wheel into, export the motion profile of trolley.
Such as Fig. 2, force analysis is carried out to robot chassis according to following rule：(1) robot body, wheel are rigid
Body；(2) two wheel geometric identities；(3) wheel is kept in contact with ground always, and wheel is non-slip when movement and only rolls
It is dynamic not slide；(4) ignore the gear clearance in actual use, sensor noise；(5) ignore the inductance in armature winding
With motor friction, motor ignores empty load of motor resistive torque when modeling, it is believed that motor output torque is electromagnetic torque；6) ignore inside
Energy loss, such as：Bearing friction etc..
In Fig. 2, the symbol point in above-mentioned force analysis figure is indicated：
R：Driving wheel radius；
Rd：Fixed point and wheel centre distance above spring；
Rk：Spring lower fixing point and center chassis distance；
ll：Left spring length；
lr：Right length；
D(t)：Two drive shaft centre distances；
θdl：Revolver axis and x-axis angle；
θdr：Right wheel axis and x-axis angle；
θz：Angle of the car body with respect to z-axis, course angle.
：The angular speed of revolver；
：The angular speed of right wheel；
Trolley and axis connection trolley are connect with spring since needs are general, dandy horse is loaded with spring under left and right wheels,
Length ll, lrIt is variations per hour, left and right wheels have respective freedom degree along vertical axis, but the no activity of two-wheel on the horizontal axis
Space may be regarded as in trunnion axis being rigid link, and it is variations per hour that rigid connection body length, which is left and right wheels distance of shaft centers D (t),.
Fig. 2 is derived using trigonometric function；It is p that relative position of the trolley mass center O point on D (t), which can be calculated,o
Place.
Further, in the step 2), mass center p is moved according to following formula counting of carriersoRelative position.
D=2 (Rk+Rd)
D be two wheelbases of trolley when static and horizontal from；
RdFor fixed point above spring and driving wheel centre distance；
RkFor spring lower fixing point and center chassis distance.
As Fig. 3 establishes double-wheel self-balancing robot kinematics model to realize motion state control：With left side wheel
For research object, resolution of velocity is carried out to robot, robot revolver speed can be obtained：Two drive shaft centre distance of D (t)；The side y
To for initial time robot direction of advance, the direction x is initial time robot car wheel shaft to if the forward speed of revolver isIf the forward speed of right wheel isComponent of the revolver speed in the direction x beComponent of the revolver speed in the direction y beθ is the yaw angle of two-wheel car.
Further, in the step 3), p in bobbin movement is calculated according to the following formulaoThe velocity magnitude V at placeOThe path and
P(t)：
Wherein, R is driving wheel radius；
RdFor fixed point above spring and wheel centre distance；
RkFor spring lower fixing point and center chassis distance；
θdlFor revolver axis and x-axis angle；
θdrFor right wheel axis and x-axis angle；
θwlFor the crank degree of revolver；
θwrFor the crank degree of right wheel；
For the rotational angular velocity of revolver；
For the rotational angular velocity of right wheel；
Further, in the step 3), simplify calculate p according to the following formulaoThe velocity magnitude V at placeOWith path P (t)：
Movement can be approximately considered θ on general two-dimensional surfacedl=θdr；poIt is approximately equal to 2 (Rk+Rd)；It can simplify
(2-3) determines that new center of mass motion formula is：
Further, in the step 4), include the following steps：
41) it is as follows to establish yaw angle function：
42) θ is calculated according to the following formuladl, θdr：
Wherein, l0For the initial length of spring；
K is the coefficient of elasticity of spring；
M is trolley quality；
G is acceleration of gravity；
L is the length of spring,
43) counting of carriers chassis path function according to the following formula, obtains the coordinates of motion O (x, y) (t) of mass center；
Wherein, θwlIt (t) is t moment revolver rotational angle；
θwrIt (t) is t moment right wheel rotational angle.
For the present embodiment by taking spring connects obstacle detouring bottom plate as an example, the spring of design such as Fig. 4 to Fig. 5 connects obstacle detouring chassis, including
Bottom plate 1 is provided with the first driving wheel 2 and the second driving wheel 3 on bottom plate 1, the first driving motor 4 is connected on the first driving wheel 2；
The second driving motor 5 is connected on second driving wheel；
The first driving motor backing plate 6 is provided with below first driving motor 4, the first driving motor backing plate 6 passes through the first bullet
Spring 7 is fixed on bottom plate 1；The second driving motor backing plate 8 is provided with below second driving motor 5, the second driving motor backing plate 7 is logical
Second spring 9 is crossed to be fixed on bottom plate 1；First driving wheel 2 and the second driving wheel 3 are symmetrical arranged along 1 middle line of bottom plate；First spring
7 are symmetrical arranged with second spring 9 along 1 middle line of bottom plate；It is additionally provided with steering wheel 10 on bottom plate 1, steering wheel 8 and the first driving wheel 2,
The distance between second driving wheel 3 is identical, forms isosceles triangle between steering wheel 8 and the first driving wheel 2, the second driving wheel 3.
As Fig. 6 to Fig. 7 emulates it using MATLAB, such as Fig. 6, according to the above method in the base of formula (2-6)
Analogue system is established on plinth.Emulation experiment starts, and two motors of left and right wheels input driving wheel angle data, fortune to kinematic system
Dynamic system exports chassis center of mass point coordinate.The revolver angular speed for inputting driving wheel is 4rad/s, and right wheel angular speed is 2rad/s.It is imitative
A length of 20s when true.Theoretically, which will do wheel rotation movement, and moving radius incrementally increases, simulation result such as Fig. 7, with experiment
As a result consistent, wherein A point is movement starting point.
In order to verify simulation result, the technical program has carried out actual measurement test, in actual bicycle undercarriage controller
On write the code of above-mentioned analogue system and do actual measurement experiment, be respectively mounted encoder, encoder after the left and right motor of bicycle undercarriage
The data of return are converted to the angle of left and right two-wheeled rotation, and the simulation model for meeting Fig. 6 design inputs, remaining in formula (2-6)
Parameter：The length of bicycle undercarriage, chassis weight, driving wheel radius, above spring under fixed point and wheel centre distance, spring
Square fixed point and center chassis distance are according to the data entry system of actual measurement.Finally obtain measured data such as Fig. 8, Fig. 9.Fig. 8
In, X-axis is the X-axis of simulating sports experiment；The Y-axis of Y-axis simulating sports experiment；In Fig. 9, X-axis is to move the X-axis of two-dimensional surface；：
Y-axis is to move the Y-axis of two-dimensional surface.
Initial phase is tested, bicycle undercarriage is located at coordinate origin, under the driving for presetting motor program, bicycle undercarriage
Setting in motion, the path that hand labeled trolley passes through in motion process, the stain measured in actual measurement path such as Fig. 9 indicate, two-wheel
The trajectory diagram of trolley output imported into Matlab and generates drawing, and if the full curve in Fig. 9 indicates, stain is substantially distributed in company
On continuous curve, mean error is controlled within 3cm.Experimental verification mathematical model discussed herein, the motion mathematical model
It can describe with the characteristics of motion of spring supporting, the dandy horse connected without real axis.
While the technical program is readily applicable to two-wheel differential shaft and connects trolley (the length setting in formula 2-6
For the acquisition that two-wheel differential shaft connects moving of car track 0) can be used for.
The preferred embodiment of the present invention has been described in detail above.It should be appreciated that those skilled in the art without
It needs creative work according to the present invention can conceive and makes many modifications and variations.Therefore, all technologies in the art
Personnel are available by logical analysis, reasoning, or a limited experiment on the basis of existing technology under this invention's idea
Technical solution, all should be within the scope of protection determined by the claims.
Claims (5)
1. a kind of robot two-wheel differential obstacle detouring bobbin movement track acquisition methods, it is characterized in that：Include the following steps：
1) rotary state of each rotating wheel is obtained；
2) obstacle detouring bobbin movement model is established, determines position of the trolley entirety mass center O point on two axles centre distance D (t)
po；
3) p in bobbin movement is calculatedoThe velocity magnitude V at placeOWith path P (t)；
4) dolly chassis path function and yaw angle function are established, the coordinates of motion of mass center are calculated；
5) it is established according to the coordinates of motion of step 4), brings the rotary state of each rotating wheel into, export the motion profile of trolley.
2. the differential obstacle detouring bobbin movement of robot two-wheel as described in claim 1 track acquisition methods, it is characterized in that：The step
It is rapid 2) in, according to mapping position of the following formula counting of carriers mass center O point on D (t) be poPlace：
D=2 (Rk+Rd)
D be two wheelbases of trolley when static and horizontal from；
RdFor fixed point above spring and driving wheel centre distance；
RkFor spring lower fixing point and center chassis distance.
3. the differential obstacle detouring bobbin movement of robot two-wheel as described in claim 1 track acquisition methods, it is characterized in that：The step
It is rapid 3) in, according to the following formula calculate bobbin movement in poThe velocity magnitude V at placeOWith path P (t)：
Wherein, R is driving wheel radius；
RdFor fixed point above spring and wheel centre distance；
RkFor spring lower fixing point and center chassis distance；
θdlFor revolver axis and x-axis angle；
θdrFor right wheel axis and x-axis angle；
θwlFor the crank degree of revolver；
θwrFor the crank degree of right wheel；
For the rotational angular velocity of revolver；
For the rotational angular velocity of right wheel；
4. the differential obstacle detouring bobbin movement of robot two-wheel as described in claim 1 track acquisition methods, it is characterized in that：The step
It is rapid 3) in, according to the following formula simplify calculate poThe velocity magnitude V at placeOWith path P (t)：
Think θdl=θdr；poIt is approximately equal to 2 (Rk+Rd)；Simplify (2-3), that is, determines that new center of mass motion formula is：
5. the differential obstacle detouring bobbin movement of robot two-wheel as described in claim 1 track acquisition methods, it is characterized in that：The step
It is rapid 4) in, include the following steps：
41) it is as follows to establish yaw angle function：
42) θ is calculated according to the following formuladl, θdr：
Wherein, l0For the initial length of spring；
K is the coefficient of elasticity of spring；
M is trolley quality；
G is acceleration of gravity；
L is the length of spring,
43) counting of carriers chassis path function according to the following formula, obtains the coordinates of motion O (x, y) (t) of mass center；
Wherein, θwlIt (t) is t moment revolver rotational angle；
θwrIt (t) is t moment right wheel rotational angle.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110348140A (en) * | 2019-07-15 | 2019-10-18 | 清华大学 | Based on towing away from two-wheel robot modeling and static balance method and device |
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| CN203658842U (en) * | 2014-01-21 | 2014-06-18 | 北京博创尚和科技有限公司 | Two-wheel differential-type autonomous mobile robot |
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| CN107422733A (en) * | 2017-07-27 | 2017-12-01 | 南京理工大学 | A kind of motion control method based on two wheel guide robot robot |
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2018
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| JPH08123551A (en) * | 1994-10-25 | 1996-05-17 | Hitachi Kiden Kogyo Ltd | Differential speed arithmetic method for four-wheel steering type automated guided vehicle |
| CN101791800A (en) * | 2010-01-21 | 2010-08-04 | 西北工业大学 | Motion control method of double-wheel differential type robot |
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| CN107024210A (en) * | 2017-03-09 | 2017-08-08 | 深圳市朗空亿科科技有限公司 | A kind of Indoor Robot barrier-avoiding method, device and navigation system |
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| CN110348140A (en) * | 2019-07-15 | 2019-10-18 | 清华大学 | Based on towing away from two-wheel robot modeling and static balance method and device |
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Application publication date: 20181120 |