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Haiping studied stability problems of the equilibrium state manifold of ... Manifold of Nonholonomic Svstems ... at the origin of the noninertial reference frame.
Mechanics Research Communications,

Vol. 28, No. 4, pp. 46%469,2CKll

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Pergamon

0 2001 Elsevier Science Ltd

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PII: SOO93-6413(01)00196-3

Stability Theorems for the Equilibrium State Manifold of Nonholonomic Systems in a Noninertial Reference Frame Luo Shaokai

Chen Xiangwei

Fu Jingli

Department of Physics Shangqiu Teachers College Shangqiu, 476000 Henan Province, P.R.CHINA

1. Introduction In 1904, Whittaker ET first studied the stability problems of the equilibrium position of nonholonomic

systems”].

Since then, Bottema 0t2], Aiserman MAt3], Karapetyan

AVt4t, Neimark UItsl, Rumyantsev

VVt4,6*71,and Mikhailov GKtS1 have done much

research on this work and obtained a series of important results, but these results are confined to linear. homogeneous and steady systems with nonholonomic constraints, and some of them are confined to Chaplygin systems. In recent years, Mei Fengxiang and Zhu Haiping

studied

nonholonomic

stability problems systems,

and

of the equilibrium

obtained

some

state manifold

important

results

of

of nonlinear considerable

generalityt9-‘31. It should be noted that all these previous works are confined to inertial reference frames, but the stability of mechanical systems in noninertial reference frames is of great significance both in theory and in practice. In this paper the stability problems of the relative equilibrium state manifold of nonlinear systems with nonholonomic

constaints in a noninertial reference frame are

studied. Firstly, the Routh equations of relative motion of these systems are constructed, and are regarded

as the relative motion of the corresponding

holonomic

systems;

moreover their relative equilibrium equations and relative equilibrium state manifold are obtained. Secondly, stability criteria for the relative equilibrium state manifold of the nonlinear nonholonomic

systems are obtained by the method of Lyapunov functions.

Finally, one example is presented to illustrate the results.

463

matter

S LUO, X CHEN and J FU

2.

Relative Eauilibrium Eauations and Relativk Eauilibrium Manifold of Nonholonomic Svstems

State

In a noninertial reference frame let us investigate the motion of a mechanical system of N particles. The configuration of the system can be specified by the generalized coordinates q,(s = l:..,n) of the noninertial reference frame attached to a massive rigid body having acceleration

translational 4r)

a,(r) , angular velocity

acceleration

independent

O(r) and angular

of the motion of each particle. For the potential and

inertial force field and inertial centrifugal force field, introduce the corresponding

force

functions

.ar:

u/o = _p = _p&,fa

u/”

=-vu

=i,.i,.,

I/, =p+c.~

o %,, ’

(1)

The nonpotential inertial forces are N

QF =-Cm,(&r;),-, ,=I

ar’

N

I,

< =-cc2

a=,,=I

ah

%’ ar: qm m,o. -xt 34,. aq,,1

where r,’ is the relative position vector of the i-th particle. and i,

(2)

is the inertia tensor

at the origin of the noninertial reference frame. Suppose that g ideal and steady nonholonomic constraints of Chetaev type are exerted on the motion of the system, i.e. fp(9,,4,)=0 where q,- =(4,,,q2~,...,q,,,)Tand

(3)

(P=J,2,.~.,g)

4? =(9,,,&,,.‘.,

Q,,,)r The relative motion equations of

the system can be expressed in Routh form as d ar, dtae,, where

ar, _a(u+u,) ----+Q,, aq.,,

a9,,

+Qp’+ ‘:+&$ a=,

(s = 1,2;..,n)

(4)

.M

T, and U are respectively the relative motion kinetic energy and the potential

function of the active force, and u = U(q, ) $~,(%)~.~,q,, s.k.1 Q, is the nonpotential active force, and d, (p = l;..,g) are undetermined T, =;

(5) multipliers.

The relative motion of the system is determined by constraints (3) and Eqs.(4). Differentiating Eqs(3) with respect to f, we have (P=l,2 ;.., g)

(6)

Substituting the expression for &, obtained from Eqs.(4) into Eqs.(6), we may obtain A,, then the A, can be obtained by solving

the equations determining the multipliers the equations and are denoted as 1.p = $&W$,)

(P = 1,2;..,g)

(7)

STABILITY

Substituting

Eqs(7)

d ar,

aq

dr %W

%.”

OF NONHOLONOMIC

SYSTEMS

into Eqs.(4), we obtain _a(u+u,) -+Q,+Q,;+

state manifold

L,, is the set of all

state manifold is t, =O]

(11)

Now suppose 0=((9,,il)(~~a(9~,~,)=0. Obviously

D

is a closed manifold

in

system. From Eqs.(S), it follows that motion

(8) corresponding

equilibrium

state manifold

P=1,2;-$1

R*“, and is called the constraint manifold D

of the

is an invariant set of the equations of relative

to the holonomic

system. Thus, the stability

L of relative motion of the nonholonomic

is equivalent

to the stability

corresponding

holonomic system (8) in the constraint manifold

3.

(12)

of the relative

eq’uilibrium

of the relative

system (3) and (4)

state manifold

L

of the

D.

Stabilitv Theorems for the Relative Eauilibrium State Manifold of a Nonlinear Nonholonomic Svstem

S LUO. X CHEN and J FU

166

Suppose that the nonlinear nonholonomic constraint equations (3) can be expressed as -9,(9,,$)=0 fa = 4(r+B,r where

(P=1,2,...,g;&=n-g)

4: = (&,,4,, ;‘., 4,)T. Suppose that the functions

(13)

9’a satisfy (14)

9)B(9, >O)= 0

and the system is subject not only to the potential force, but also to the active force and the dissipative force of the generalized force of inertia of rotation as follows I,

F, = -2 k.\,,,(9,)G”,, .I=,

F,, = -c

.,=I

k,,,, (9, )(i,

Let F,‘=F,+F,,

kl, = km + k,,,,,,

From the relative equilibrium equations (9). we know that the relative equilibrium states of relative motion of the system comprise a manifold of dimension not less than the number g of constraint equations. Let V = T, -Cl -II, From the equations

of motion (8) of the corresponding

holonomic system, we obtain (15) where the 9p can be expressed as (16) Obviously,

9;l satisfies Qb/,,;;, = 0,

F

=o a satisfy

-Z$&)=

~G(9A)%~~, 0.h=, CW K&(L) = 0 Substituting Eq.( 19) into Eq.( 17), we obtain r; = - T(z;

-K&)&&

V.kl

where His at least of order three in ;3:, and zk is

+H

(19)

(20)

STABILITY

OF NONHOLONOMIC

SYSTEMS

467

(21)

If

the dissipative

generalized infer that

force

velocity ti

f,’

is negative

negative definite for

is completely

9:) then the matrix

9:

definite

for

dissipative

(6)

9:

with

respect to the isolated

is positive definite.

in some neighborhood

From Eq.(20),

of L

we

. Hence ri is

in the constrained manifold as follows

D=((9,,9,)/4,c+fi,,

P = 1,2,...,gJ

-~jA9,,4:)=0,

(22)

So we have constraints (13) U(q,) + O,(q,) is negative definite and bounded with respect to L,, , and grad(U + U, ) = 0 holds at every point of L,, , then

Theorem 1

For the conservative mechanical system with nonholonomic

and satisfying condition

the

relative

asymptotically

equilibrium

of (14), if its force function

state

manifold

L

of

relative

motion

of

stable with respect to a dissipative force that is completely

the

system

is

dissipative with

respect to the isolated generalized velocities.

Theorem 2

For the conservative

mechanical system with nonholonomic

and satisfying condition of (14), if its force function

constraints (13)

U(q,.)+ U, (4,) is non-negative and

bounded with respect to L,, , and grad(U + U, ) = 0 holds at every point of relative equilibrium

state manifold

L,, , then the

L of relative motion of the system is unstable with

respect forces that are completely

dissipative

with respect to the isolated generalized

velocities.

4.

An Examtde

Suppose the carrier of the reference frame rotates with an uniform

angular velocity

w

around a fixed axis. The kinetic energy of relative motion of the system is r, = $4;

+ 9:, + 4;; )

(23)

and its force function is U’=lJ+U.

+q,,

The system is subject to the nonholonomic

+qzr +9,,)2wz

(24)

constraint as follows

93, + 9, (9, )4:, + 92 (9, )&, = 0 where

a, and n2 are functions of the generalized coordinates

(25)

q, = (9,,,qZ, ,q,r)T. The

system is acted upon by a dissipative force with dissipation function (26)

368

S LUO,

where p, >O,

pz>O.

X

CHEN

and .l. FU

p,bO.

The equations of relative motion of the corresponding holonomic system are 91, = -(9,r + 92, + 93, )a2 - P,4,, + 2% 92, = -(9,, + 92r-+ 93, )J

A

- P*92, + 2%9,,~

4;, = -(9,, + 92, + 9,#.W -PA

(27)

+a

From the constraint equation (25) and Eqs.(27), we obtain R = (9,, + qzr + 9,r)(l +29,9,,

+ 29,9,,W

+ 2P,9,9:

I+ 4af&

+ 2j+G:,

+ PA,,

-&Z,

- G,

+ 4a:$, (28)

From the relative equilibrium equation of relative motion (9), we obtain the relative equilibrium state manifold of the system as L = {(909, )19,, + 92, + 93, = 0.

9, = 01

(29)

Obviously, the force function LI’ is negative definite on L,, = and

gradCI’ = 0

holds at every point of

L,,

{q,[q,, + 9tr + 9,, = 0) ,

From Theorem

I,

we know L is

asymptotically stable. If the force function (24) equilibrium

is changed to

II’ = i(9,r

state manifold of the system is still Eq.(29).

positive definite for L,, , and C/‘(L,,) = 0

+ q2, + q3, )202

, then the

The force function U’

is

; moreover gradll’ = 0 holds at every point of

L,, From Theorem 2, we know that L is unstable.

References I.

Whittaker

E T. A treatise on the analytical

dynamics of particles and rigid bodies with an

introduction to the problem of three bodies. Eng: Cambridge, 1904.221-225

2.

Bottema 0. On the small vibrations of nonholonomic systems. Proc Kon ned akad wet, 1949, 52(8): 848-850

3. Aiserman M A, Gantmacher F R. Stabilitat der Gleichgewichtslage in cinem nichtholonomen system. ZAMM,

4.

I951.37( I-2): 74-15

Karapetyan A V. Rumyantsev V V. Stability of conservative and dissipational systems. Moscow: VINITI,

1983. 55-62(in Russian)

5. Neimark U I, Fufaev N A. Dynamics of nonholonomic systems. Moscow: Nauka, 1967. 241-296(in Russian)

6.

Rumyantsev V V. On the stability of motion of nonholonomic 1967, 31(2): 260-27l(in

systems. Appl. Math. And Mech.,

Russian)

I.

Rumyantsev V V. On the asymptotic stability and instability of motion with respect to part of the

8.

Mikhailov

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V Z. Applied

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SYSTEMS

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Mei Fcngxiang. On the stability of equilibrium of nonlinear nonholonomic systems. Chinese Science Bulletin,

1992,37

(

1) : 82-85

JO. Zhu Haiping, Mei Fengxiang. Relations between the stability with respect to part of the variables and that with respect to all of the variables for a nonholonomic 1994.39

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(2)

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motion for a nonlinear nonholonomic

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Journal. 1994.10(2): 38-42 12. Zhu Haiping. Stability theorems of equilibrium state manifold for a nonlinear nonholonomic system. Huanghuai Journal, 1995.11(3): 16-19 13. Zhu Haiping, nonholonomic

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