CN103042525A - Method for determining anti-disturbance capacity of humanoid robot - Google Patents

Abstract

The invention discloses a method for determining the anti-disturbance capacity of a humanoid robot and belongs to the technical field of robots. The method includes performing modeling by using a linear inverted pendulum model according to parameters of the humanoid robot; and under the condition that the inverted pendulum model is disturbed, according to a steady judging criterion ZMP theory of the humanoid robot, when the projection of the mass center point of the robot reaches a tiptoe, calling the state in which the speed of the robot is just reduced to zero as a limit steady state. According to the method, the anti-disturbance capacities of the robots are evaluated according to the maximum external force disturbances of different robots when limit steady states are reached, the calculation is simple, parameters related to stability of the robot are considered, and anti-disturbance capacities of different humanoid robots can be fine determined.

Description

A kind of method of Ability of Resisting Disturbance of definite anthropomorphic robot

Technical field:

The invention discloses a kind of method of Ability of Resisting Disturbance of definite anthropomorphic robot, belong to the Robotics field.

Background technology:

Anthropomorphic robot has people's resemblance, can adapt to better human living environment, thereby is people's service better.In recent decades, started the upsurge of research anthropomorphic robot both at home and abroad, its research contents mainly comprises the aspects such as stabilized walking, dexterous operation, man-machine interaction, Expression Recognition.

The double feet walking of anthropomorphic robot is the process of a complexity.In order to describe the most basic walking ability of anthropomorphic robot, many kinetic models are established, and are more common such as based on two connecting rod models of single leg, three connecting rod models with based on inverted pendulum model, five connecting rod models and the seven-link assembly model of both legs.Wherein, all quality of inverted pendulum model supposition robot upper body nearly all concentrate on the waist center, and the quality of foot and leg can be ignored with respect to the quality of upper body.This inverted pendulum model is widely used in anthropomorphic robot double feet walking field.

In recent years, because the demand of the anti-unknown disturbances of safety and robot of man-machine interaction, more and more received an acclaim based on the research of the anthropomorphic robot of power control.As a kind of common man-machine interaction mode, the research of the anti-thrust of robot becomes the jamproof example of a kind of typical research robot.

In general, thrust can make robot produce an extra initial velocity to robot a period of time with it, and robot will produce a new motion and recover suffered interference.Has different Ability of Resisting Disturbances according to the resulting anthropomorphic robot of different dynamic modeling methods.Up to the present, the method that does not also have a kind of definite anthropomorphic robot Ability of Resisting Disturbance size.The momentum of the maximum that Most scholars all simply can be subject to anthropomorphic robot divided by robot whole body quality as judgment criterion.But these two parameters can not illustrate the Robot Robust size fully, because the height of the size of the pin of anthropomorphic robot and mass centre's point (COM) also can affect the Ability of Resisting Disturbance of robot.Do not utilize the height of the size of pin of anthropomorphic robot and mass centre's point to determine the method for the Ability of Resisting Disturbance of anthropomorphic robot in the prior art.

Summary of the invention:

In order to solve problems of the prior art, the object of the present invention is to provide a kind of simple efficiently appraisal procedure of the Ability of Resisting Disturbance of anthropomorphic robot.The technical solution used in the present invention is as follows:

A kind of method of Ability of Resisting Disturbance of definite anthropomorphic robot said method comprising the steps of:

According to the anthropomorphic robot parameter, with inverted pendulum model to its modeling;

Theoretical according to the orbital energy of linear inverted pendulum, obtain the initial velocity V that robot is subjected to mass centre's point after the thrust ₀

According to robot stabilized criterion ZMP theory and momentum theorem, calculate the maximum perturbation that this anthropomorphic robot can be subject to;

Determine the Ability of Resisting Disturbance of this anthropomorphic robot according to the suffered different maximum perturbation of this anthropomorphic robot.

Preferably, the step of this anthropomorphic robot of described calculating maximum perturbation that can be subject to comprises: obtain the maximum interference momentum I that robot can bear _Max

Preferably, describedly determine that according to the suffered different maximum perturbation of this anthropomorphic robot the step of the Ability of Resisting Disturbance of this anthropomorphic robot comprises: the maximum thrust that can bear according to this anthropomorphic robot, set up assessment anthropomorphic robot Ability of Resisting Disturbance criterion, the jamproof robustness evaluation criterion of anthropomorphic robot is:

$K_{\mathrm{robust}}=\frac{I_{\max }*T_C}{M*L_{\mathrm{ff}}}$

In the formula,

H _COMThe height of representation quality central point, g represents acceleration of gravity, L _FfRepresent the length of the robot forward foot in a step, M is the gross mass of robot; K _RobustBe worth greatlyr, then this robot Ability of Resisting Disturbance is stronger, otherwise then less.

By above technical scheme, this method can according to make different anthropomorphic robots reach capacity stable state the maximum external force disturbance vary in size to assess the robot Ability of Resisting Disturbance.

Description of drawings:

Fig. 1 is anthropomorphic robot inverted pendulum model figure involved in the present invention.

Fig. 2 is that inverted pendulum involved in the present invention is from being subjected to disturbance to the schematic diagram of limit stability state.

The specific embodiment:

Below in conjunction with accompanying drawing the specific embodiment of the present invention is described in further detail.

ZMP is with a relevant concept of anthropomorphic robot dynamic stability.So-called ZMP, the moment that is ground force is that point of zero; So-called support polygon, the i.e. minimum polygonal region that has point of contact between at the bottom of the robot foot and the ground.Make apery robot stabilized walking, its ZMP must be arranged in support polygon all the time.

When robot will recover from more intense outer force-disturbance, robot can produce one with thrust direction horizontal component initial velocity V in the same way ₀Can to robot apply one and V at the bottom of the robot foot this moment ₀The component of opposite direction stops the robot motion.After supposing that robot is subject to thrust, heel is liftoff rapidly, and namely the suffered ground reaction force of robot is all from the tiptoe position.In this case, can be reduced to a linear inverted pendulum model (Fig. 1) to the machine human motion, robot and ground contact point are tiptoe, and people from robot mass concentration is at a point, and initial velocity is V ₀

After robot is subject to the tiptoe counter-force, can retarded motion.When if robot mass centre's point does not also arrive tiptoe in the projection on ground, it is zero that robot has slowed down, and robot will resist interference in this case, gets back to the origin-location; If robot mass centre's point ground project to tiptoe the time, the robot speed is also non-vanishing, its projection will exceed the stability region in this case, makes robot unstable; And when robot mass centre's point ground project to tiptoe the time, the robot speed just is kept to zero, this moment, robot just was in stable state (Fig. 2).So claim this kind state, after namely robot was subjected to external force, mass centre's point was called robot limit stability state in the time of can just being decelerated to the tiptoe position.

Can make the reach capacity interference of stable state of robot be called the maximum interference that robot can be subject to.Different robots, the maximum interference that it can be subject to is different.Therefore, in order to determine different machines people's Ability of Resisting Disturbance size.When setting up assessment level, we at first will assess the limit stability state of this robot.

Threshold condition is the position that the ZMP of robot stops at tiptoe, and is theoretical according to the orbital energy of linear inverted pendulum (such as Fig. 1), can learn that the energy of inverted pendulum after just being subjected to thrust is:

$\frac{1}{2}{\mathrm{MV}}_0^2=E_1---\left(1\right)$

Wherein, M is the gross mass of robot, V ₀Representative is subjected to the speed of COM after the thrust, E ₁Represent the orbital energy of this moment.

The energy of inverted pendulum when limiting condition is:

$\frac{\mathrm{Mg}}{2H_{\mathrm{COM}}}{L}_{\mathrm{ff}}^2=E_2---\left(2\right)$

H in the formula _COMRepresent the height of COM, g represents acceleration of gravity, L _FfRepresent the length of robot model's forward foot in a step.E ₂Represent the orbital energy of this moment.

According in the motion of linear inverted pendulum, orbital energy conservation, as can be known E ₁=E ₂So:

$\frac{1}{2}{V}_0^2=\frac{g}{2H_{\mathrm{COM}}}{L}_{\mathrm{ff}}^2---\left(3\right)$

In formula (3), V ₀Be equivalent to the maximal rate V that robot can recover _Max, therefore

$V_{\max }=V_0=\sqrt{\frac{g}{H_{\mathrm{COM}}}}{L}_{\mathrm{ff}}---\left(4\right)$

According to momentum theorem,

$V_{\max }=\frac{I_{\max }}{M}---\left(5\right)$

I in the formula _MaxBe the momentum of the maximum that robot can be stable, M is the gross mass of robot.

For standardization, the jamproof robustness evaluation criterion of anthropomorphic robot is

$K_{\mathrm{robust}}=\frac{I_{\max }*T_C}{M*L_{\mathrm{ff}}}---\left(6\right)$

In the formula,

Different anthropomorphic robots can be assessed this robot antijamming capability size according to formula (6).

In formula (6), we are according to the gross mass M of different anthropomorphic robots, the length L of the robot forward foot in a step _Ff, the height H of COM during the robot initial state _COMAnd the maximum thrust I that can be subject to of robot _MaxDetermine the Ability of Resisting Disturbance of this robot.The K that calculates and calculate in the formula (6) _RobustRepresent the Ability of Resisting Disturbance criterion of anthropomorphic robot, the K that calculates by this model parameter _RobustBe worth greatlyr, then this robot Ability of Resisting Disturbance is stronger, otherwise then less.

As can be seen from the above description, the invention provides a kind of method of jamproof ability of definite anthropomorphic robot.The size of the pin of the method consideration anthropomorphic robot and the height of mass centre's point (COM) are on the impact of robot stabilization; The method is calculated simple, only needs can calculate this anthropomorphic robot Ability of Resisting Disturbance size according to the stable relevant parameter of robot by the interpretational criteria equation, can reach the size of well determining different anthropomorphic robot antijamming capabilities.

Claims (3)

1. the method for the Ability of Resisting Disturbance of a definite anthropomorphic robot said method comprising the steps of:

According to the anthropomorphic robot parameter, with inverted pendulum model to its modeling;

Theoretical according to the orbital energy of linear inverted pendulum, obtain the initial velocity V that robot is subjected to mass centre's point after the thrust ₀

According to robot stabilized criterion ZMP theory and momentum theorem, calculate the maximum perturbation that this anthropomorphic robot can be subject to;

Determine the Ability of Resisting Disturbance of this anthropomorphic robot according to the suffered different maximum perturbation of this anthropomorphic robot.

2. the method for the Ability of Resisting Disturbance of definite anthropomorphic robot according to claim 1, the step of the maximum perturbation that this anthropomorphic robot of wherein said calculating can be subject to comprises: obtain the maximum interference momentum I that robot can bear _Max

3. the method for the Ability of Resisting Disturbance of definite anthropomorphic robot according to claim 2, wherein saidly determine that according to the suffered different maximum perturbation of this anthropomorphic robot the step of the Ability of Resisting Disturbance of this anthropomorphic robot comprises: the maximum thrust that can bear according to this anthropomorphic robot, set up the different anthropomorphic robot Ability of Resisting Disturbance criterions of assessment, the jamproof robustness size of anthropomorphic robot interpretational criteria is:

$K_{\mathrm{robust}}=\frac{I_{\max }*T_C}{M*L_{\mathrm{ff}}}$

In the formula, H _COMThe height of representation quality central point, g represents acceleration of gravity, L _FfRepresent the length of the robot forward foot in a step, M is the gross mass of robot; K _RobustBe worth greatlyr, then this robot Ability of Resisting Disturbance is stronger, otherwise then less.

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