SU1282014A1 - Method of determining actual velocity of crawler vehicle - Google Patents

Abstract

The invention relates to methods and means of researching machines and reduces the measurement errors of the actual speed. The device implementing the method contains acceleration sensors 1, 2 and 3, a rotation angle sensor 4 and an angular velocity sensor 5, the signals from which are fed to amplifier 6 and recorded on an oscilloscope tape 7. For fixed time points, the measured acceleration values are determined in a given direction, rotation angle and rotation frequency for each driving star. Based on their results, the three components of the acceleration and the peripheral speed of the drive sprocket are calculated. Based on the results of the calculations, the acceleration components are integrated. From the result, subtract the appropriate amount of circumferential velocity. As a result, the axle speed components of one drive wheel are obtained, and the vehicle velocity components are calculated according to the formulas described in the invention. 9 il. (L

Description

D ..

fig.b

The invention relates to methods and means of researching machines and serves to determine the actual speed of tracked vehicles moving on rough terrain with variable speed in magnitude and direction, with varying amounts of skidding.

The purpose of the invention is to reduce the measurement error of the actual speed of a tracked vehicle and to expand the scope.

Figs. 1 and 2 show vector diagrams characterizing the proposed method; Fig. 3 shows the installation of the acceleration sensor in the direction normal to the radius of the drive sprocket and the unit vectors of the selected coordinate system; Fig. 4 shows the installation of the acceleration sensor in the direction parallel to the axis of the leading sprocket, and respectively the rotated system of unit vectors, in FIG. 3 —the installation of the acceleration sensor 3 in the direction along the radius of the driving sprocket and the system of single vectors; FIGS. 6 and 7 are a block diagram of the device for implementing tim proposed method.

When implementing the device according to the block diagram of FIG. 6, the measured values are fixed on an oscilloscope tape for further analysis and speed calculation.

FIG. 1 and 2 denote unit vectors Xj of a fixed coordinate system (J 1,3), indices, 1, 2 points of the tractor frame (frame) lying in the longitudinal plane of symmetry, points of the left and right driving wheels, respectively, radius vector S, - sensors accelerations; radius - century. torus Rj; (t, x) axes of leading sprockets, radius g; (t) rotation of acceleration sensors (i leading sprocket), radius - vector R () of the tractor's skeleton point, radius - vector) of the contact point of the leading sprocket with the supporting surface, vector B (x, t) offset of the instant rolling speed Depending on the size of the slip of the track chain, the vector R (x), () is normal to the bearing surface, equal in magnitude to the geometric radius of the quality of the drive sprocket (R t T B), column B of the tractor.

Taking into account the accepted notations, a vector equation system is obtained:

R

Oci

 k.-4v

 R.

and

radius vector (O

Ocj

.dR, dt

dR dt

1Ui

2dt

+ -

one

2dt

- speed

Thus, the speed of the point of the tractor's core lying in the plane of the longitudinal symmetry and the plane perpendicular to it and passing through the axes of rotation of the drive sprockets is determined by the formula

 (V 2 "h

+ V)

(2)

The speed of the leading sprocket axis is found from the equations:

25

Y „

dRee dR -, (xJ dt dt

If we measure the acceleration of a point of a leading sprocket with a radius vector S in a fixed coordinate system, then we make the subsequent 1 | integration, get the speed V by the formula:

V JaCt) dt + V

The sensor measures the acceleration along its axis xended to it, so a system of three sensors will measure the accelerations along three fixed axes. If d is the acceleration value,

measured by the sensor along its axis, the acceleration vector a will be

a - 1 ±

In the proposed method, the acceleration sensors are oriented along the radius r along the normal to it in the plane of rotation of the drive sprocket and along the normal to this plane of rotation.

By measuring the acceleration vector a, the current angle of rotation, the angular velocity u3j, and the magnitude of (r1), one can calculate the vector of the absolute velocity of motion (V.) of a given point of the drive sprocket.

. You can calculate the circumferential speed V t3. xg and portable speed

Ok t

axles:

wasps

 Vi - Vo

Z-axis speeds

, it is possible to calculate the speed of movement of the tractor frame V.

In the proposed method, both the magnitude and the direction of the actual speed of the tractor frame are measured, regardless of the topography of the soil and the type of movement of the tractor.

When the device is implemented according to the block diagram (Fig. 9), the measurement results are processed in the onboard microprocessor, and the speed and direction are displayed on the device screen in the cab of the tracked vehicle.

The device for carrying out the proposed method contains three acceleration sensors measuring accelerations: 1 - in the direction normal to the radius of the drive wheel, 2 - parallel to the axis of the drive sprocket, 3 - along the radius of the drive sprocket, angle sensor 4, angle sensor 5, amplifier 6 and oscilloscope 7, analog-to-digital converter 8, microprocessor 9 and indicator 10.

The method is carried out as follows.

The signals of the sensors 1-5 (Fig and 9) served in the amplifier 6 and register either on the tape of the oscilloscope 7, or convert from analog form to digital code B analog-to-digital Converter 8.

The waveform for fixed points in time determines the measured values of accelerations in a given direction, the angle of rotation and the frequency of rotation for each driving sprocket. From the results of these measurements, the three components of the acceleration are calculated for selected points in time, the peripheral speed of the drive sprocket. According to the results of the calculation, the acceleration components are integrated, and the corresponding component of the peripheral velocity is subtracted from the result. As a result, the axle speed components of one drive wheel are obtained. Thereafter, these calculations are performed to determine the speed components for the other star star and the vehicle speed components are calculated using the above formula.

Consistently calculate the components of the vehicle speed

For fixed times, find the magnitude and direction of the speed of the vehicle at any time.

Claims (1)

Invention Formula A method for determining the actual speed of a tracked vehicle, which consists in measuring the frequency of rotation of a wheel of a predetermined diameter fixed on the vehicle body with the possibility of rolling relative to the ground, and, in order to reduce the error and expand the field of use, The rotational speeds of the two leading sprockets of the vehicle are measured, and the acceleration is measured at three times. mutually perpendicular directions on, given distances from the axes of rotation of the asterisks, and the speed is determined by the formula (t) | (V 2 01 (t) 0 five 0 five 0 five ,: .d, where (t) jr (t) dt + v; ,, -V, is cKo-J. pocTb axis right () or left () leading Zbezdochek, V A, xg (h-) - circumferential. Growth 1 - leading star, ai (t) i ° + (d ,,, + d5, sin,) i2 + + (d ,; sin 4. + d, j consistently, -) ,, is the acceleration measured at a given distance r from the axis i - leading sprocket,, d ,, - - acceleration, measured by sensors installed at specified distances for i - leading sprocket in three mutually perpendicular directions: perpendicular to the radius, parallel to the axis of the leading sprocket, along. radius, the current angle of rotation of the radius relative to the normal to the circumference of the drive sprocket at its point of contact with the bearing surface; angular velocity i -ve.- of the asterisk; 4, (t) 3, (t) the initial speed of the i - leading sprocket at the installation site of the acceleration sensors; ) is the predetermined distance from the axis of rotation of the i-leading sprocket to the point where the acceleration sensors are installed. Phage2 to Fig4 FIG. five srag.7