CN102759923A - Control method for bionic dual-feet robot walking on water - Google Patents

Abstract

The invention relates to a control method for a bionic dual-feet robot walking on the water and provides a CPG (Central Pattern Generator)-fuzzy combination control carried on a robot. The CPG generates an oscillation signal for realizing the control over rhythmic exercises of robot dual feet. The fuzzy control is used for compensating dynamic balance of the dual-feet robot walking on the water in the left and right direction; and a feedback signal output by an angle measuring module can be used for carrying out feedback control on a CPG module and a fuzzy control module. The CPG-fuzzy combination control provided by the invention can provide reference for the control theory of walking on the water of the dual-feet robot and achieve the function of walking on the water.

Description

Bionical biped overwater walking robot control method

Technical field

The invention belongs to the bionics technical field, relate to the control method that a kind of bionical biped robot realizes the floating walking function.

Background technology

Robot waterborne can work on the water surface of danger or swampland, has purposes widely in environment measuring, military investigation, water pollutant and fields such as the detection of poisonous element, wetland detection.The floating mechanism of present robot waterborne has following three kinds of supporting way: surface tension supports; Buoyant support; Generate the support that air pocket produces through patting liquid.Surface tension supports and to require that robot is in light weight, volume is little and material waterproofing.Buoyant support is to utilize buoyancy of liquid to process robot, and buoyancy is big, is fit to large-scale robot, and these two kinds of methods all have the shortcoming that gait of march is slow, useful load is low.Inspired by South America basilisk lizard, utilize the robot sole to bounce the water surface, force under water heavy or from the sole diffuse underneath, above sole and around form air pocket, produce anchorage force upwards and driving force forward, thereby realize floating walking.External environment is difficult to modeling during biped robot's floating walking, gait planning validity is low, water surface interference strength is very big, and traditional accurate kinematics solution method based on model can't be suitable for.

Summary of the invention

The objective of the invention is the biped robot based on basilisk lizard floating walking mechanism is applied control, realize the floating walking of robot.It is significantly different that aquatic environment and terrestrial environment have, and environmental perturbation can't be avoided during the robot floating walking, and gait planning is difficult to carry out, and traditional control method can't be suitable for.

In order to realize floating walking, the present invention proposes a kind of CPG-Fuzzy Combined control method.At first utilize the Mechatronic Systems associative simulation to obtain the mathematics of control model of biped overwater walking robot; Make up the initial model of CPG control module and fuzzy control model; Rhythmic exercise to the robot sole applies CPG control then; Balance to the robot left and right directions applies fuzzy control, and passes through the pitch angle of the real-time robot measurement of incline measurement module, and the signal that obtains carries out feedback adjustment to the output of fuzzy control and CPG control.

Said biped overwater walking robot mathematics of control model is in dynamics analysis software, to set up the virtual prototype model; On the basis of Mechatronic Systems associative simulation, obtain then, external environment obtains through applying equal power the effect of biped robot's sole.

Said CPG control module initial model utilizes two-way Hopf oscillator to make up, and utilizes two Hopf neurons to connect mutually and obtains bi-directional oscillating device network, produces two-way output signal.

Said fuzzy control model initial model is the angle of inclination that obtained by the incline measurement module and rate of change thereof as the input language variable.

The CPG control of said robot foot propodite rule motion is that the two-way output signal that utilizes the CPG control module to obtain is regulated; Through regulating the parameter of CPG module; Can obtain having the two-way output signal of different frequency and phase relation; Be applied to biped robot's sole, can obtain the different motion relation of robot sole.

The fuzzy control of said left and right directions, the output of fuzzy control model are used for the mobile equilibrium on the robot left and right directions is compensated control.

Said pitch angle detection module is to be drawn by gyroscope, accelerometer measures, and the feedback signal that obtains is used for the parameter of fuzzy control model and CPG module is adjusted.

Beneficial effect of the present invention:

The complex dynamic modeling has been avoided in biped overwater walking robot CPG-Fuzzy Combined control proposed by the invention, has overcome the not strong shortcoming of traditional control method robustness; Through adjustment to the CPG module parameter, can realize having the gait of the multiple phase relation and the speed of travel, be easy to the strike waters raising force that produces and the size of driving force of sole adjusted; Through fuzzy control; Overcome significantly disturbance of aquatic environment, set up a fuzzy control table, table look-at output control signal in the robot operational process; Reduce the great amount of calculation time, strengthened real-time.Through the CPG-fuzzy control, can realize biped robot's floating walking function.

Description of drawings

Fig. 1 is bionical biped overwater walking robot control structure synoptic diagram;

Fig. 2 is bionical biped overwater walking robot control hardware block diagram;

Fig. 3 is bionical biped overwater walking robot Control Software process flow diagram.

Embodiment

For making the object of the invention, technical scheme and advantage clearer, for example the bionical biped overwater walking robot of the present invention control method is made below in conjunction with accompanying drawing and to be elaborated.

One, the CPG-Fuzzy Combined control system of bionical biped overwater walking robot

Fig. 1 has provided the bionical biped overwater walking robot control structure synoptic diagram of the inventive method, comprises biped overwater walking robot physical construction, robot mathematical model, the initialization of CPG model parameter, CPG model, fuzzy control parameter initialization, fuzzy control model and pitch angle detection feedback module.The mathematical model of biped overwater walking robot is the nonlinear model that is obtained by the Mechatronic Systems associative simulation.The joint of two leg exercises of overwater walking robot is to be controlled by the oscillator signal of CPG model output.Establish guide rail among Fig. 1 in the overwater walking robot; Guide rail is provided with the quality bead; During the robot floating walking, realize the mobile equilibrium on the left and right directions through the quality of regulation bead in the position on the guide rail, the position of quality bead on guide rail is by the output signal deciding of fuzzy control model.Through regulating the parameter of CPG model, can regulate needed raising force of floating walking and driving force.

Two, the mathematical model of bionical biped overwater walking robot

The bionical biped overwater walking robot mathematical model block diagram of the inventive method comprises state space module and nonlinear S function module of a linearity, and this module obtains through the Mechatronic Systems associative simulation.Biped overwater walking robot environmental abnormality of living in is complicated, is difficult to set up linear model, obtains nonlinear model through the Mechatronic Systems associative simulation, and external environment comes equivalence to realize the influence of robot through applying equal power.

Three, the CPG modular model of CPG-Fuzzy Combined control system

The CPG model of bionical biped overwater walking robot need be set up in the CPG model parameter initialization procedure in Fig. 1, and the CPG model of robot is that the two-way Hopf oscillation network that utilizes the Hopf oscillator to set up is realized.Two-way Hopf oscillation network mathematical model is as follows:

$x_i^{\′}=({\mathrm{\μ}}_i-{\mathrm{\γ}}_i^2)x_i+{\mathrm{\ωy}}_i+\underset{j=1,j\≠i}{\overset{n}{\mathrm{\Σ}}}{a}_j{x}_j---\left(1.1\right)$

$y_i^{\′}=({\mathrm{\μ}}_i-{\mathrm{\γ}}_i^2)y_i-{\mathrm{\ωx}}_i---\left(1.2\right)$

$x_{i+1}^{\′}=(u_{i+1}-{\mathrm{\γ}}_{i+1}^2)x_{i+1}+{\mathrm{\ωy}}_{i+1}+\underset{j=1,j\≠i+1}{\mathrm{\Σ}}{a}_j{x}_j---\left(1.3\right)$

$y_{i+1}^{\′}=({\mathrm{\μ}}_{i+1}-{\mathrm{\γ}}_{i+1}^2)y_{i+1}-{\mathrm{\ωx}}_{i+1}---\left(1.4\right)$

In the formula,

a _jBe that oscillator connects weights, x _i, x _I+1Be respectively the output of two oscillators, μ _iInfluence the amplitude of i oscillator, μ _I+1Influence the amplitude of i+1 oscillator, ω influences the frequency of oscillator, y _i, y _I+1It is the built-in variable of oscillator.

Biped overwater walking robot two legs respectively has a direct current generator, and the above-mentioned formula when getting n=2 is as the mathematical model of biped overwater walking robot CPG module.Through regulating the value of μ and ω, can realize having the gait of different rates and phase relation.

Four, the fuzzy control model model of CPG-Fuzzy Combined control system

Fuzzy control model of the present invention is the angle of inclination and the rate of change thereof that detect feedback module output with Fig. 1 medium dip angle as the input language variable; The output of fuzzy control model is used for the displacement of establishing the quality bead in the robot waterborne in the control chart 1, and the mobile equilibrium on the biped robot waterborne left and right directions is compensated.Input language variable and output language variable all have negative big, negative in, negative little, zero, just little, center, honest seven language values, membership function selection Gaussian.

Five, the CPG-Fuzzy Combined hardware control system of bionical biped overwater walking robot and software are realized

Fig. 2 has provided the control hardware block diagram of bionical biped overwater walking robot, and Fig. 3 has provided the Control Software block diagram of bionical biped overwater walking robot.The control hardware block diagram comprises power module, gyro module, accelerometer module, digital signal processor module, drives amplification module, encoder feedback module, and the motion performance element: left leg direct current generator, right leg direct current generator, steering wheel.Power module provides power supply to The whole control system.Gyroscope and accelerometer are gathered the pitch angle of overwater walking robot in real time; Carry out sending into digital signal processor processes after the AD conversion; After the output signal amplifies through overdriving; Be used for controlling the steering wheel of establishing the little displacement of ball of quality in direct current generator and the walking robot of the direct current generator of left leg joint, right leg joint respectively; The direct current generator of control left and right sides leg joint makes robot obtain to maintain the raising force on the water surface, and the displacement of control steering wheel and then control of quality bead realizes the mobile equilibrium on the left and right directions.

The Control Software block diagram of bionical biped overwater walking robot comprises: start module, CPG control module parameter initialization, fuzzy control model parameter initialization, output control signal module, measure inclination angle module and judge module.In CPG control module parameter initialization, change into corresponding difference equation to the differential equation of setting up in formula (1.1)-(1.4), and the variable in the equation is provided with suitable initial value.In the fuzzy control model parameter initialization, the angle of inclination of selected Fig. 1 medium dip angle detection feedback module output and rate of change thereof are as the input variable of Fuzzy control system.Establish the output variable of the displacement of quality bead in the selected robot as Fuzzy control system.Inference method is selected the Mamdani type, delimits basic domain, and carries out the quantification of basic domain to discrete-time fuzzy set theory territory; The language value of selected linguistic variable is provided with the subordinate function shape, carry out fuzzy reasoning after; Generate fuzzy polling list, be used for the control of bionical biped overwater walking robot.

Obviously, above-mentioned embodiment of the present invention only be for clearly the present invention is described and is done for example, and be not to be qualification to embodiment of the present invention.For the those of ordinary skill in affiliated field, on the basis of above-mentioned explanation, can also be easy to make other pro forma variation or substitute, and these change or substitute and also will be included within the protection domain that the present invention confirms.

Claims (6)

1. bionical biped overwater walking robot control method; It is characterized in that; Rhythmic exercise for the robot shank adopts the oscillator signal that produces based on the CPG mathematical model to control, and fuzzy control compensates the left and right sides mobile equilibrium of robot, and the modeling of robot body and external environment obtains through electromechanical combination emulation; The pitch angle detection module feeds back to fuzzy control model and CPG module with the pitch angle that obtains, and forms closed loop and is used for the motion of robot is adjusted.

2. bionical biped overwater walking robot control method according to claim 1 is characterized in that, the rhythmic movement of foot of described robot is produced by the CPG mathematical model, and the CPG mathematical model is made up of two Hopf oscillators of two-way connection.

3. bionical biped overwater walking robot control method according to claim 1; It is characterized in that; Described fuzzy control is the input language variable with the angle that departs from vertical axes on the robot left and right directions and the rate of change of angle, and the displacement of (7) is the output language variable.

4. bionical biped overwater walking robot control method according to claim 1; It is characterized in that; Described pitch angle detection module is to be drawn by gyroscope, accelerometer measures, and the feedback signal that obtains is used for the parameter of fuzzy control model and CPG module is adjusted.

5. bionical biped overwater walking robot control method according to claim 1 is characterized in that described biped overwater walking robot body and external environment mathematical model obtain through the Mechatronic Systems associative simulation, and this model is non-linear.

6. bionical biped overwater walking robot control method according to claim 1 is characterized in that, described CPG-Fuzzy Combined is controlled, and is used for realizing the floating walking of robot, and bionical biped overwater walking robot is maintained on the water surface.

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