Course project "Traction calculation of a tracked machine taking into account curvilinear movement"

Contents

1 INTRODUCTION

2 Traction calculation of caterpillar machine

2.1 Calculation and construction of engine characteristic

2.1.1 Determination of maximum effective engine power

2.1.2 Calculation and construction of engine external speed characteristic

2.1.3 Calculation and construction of free power and free

engine torque

2.2 Calculation of transmission characteristics

2.2.1 Calculation of transmission range

2.2.2 Calculation of the number of gears

2.2.3 Calculation of speeds in each transmission

2.2.4 Calculation of transmission gear ratios

2.3 Calculation of traction characteristic of straight machine motion

2.3.1 Calculation of machine speed in gears

2.3.2 Calculation of specific thrust force of the machine

2.4 Calculation of engine acceleration characteristics

2.4.1 Calculation of acceleration characteristics of the machine at the first stage

2.4.2 Calculation of acceleration characteristics of the machine at the second stage

2.4.3 Calculation of acceleration characteristics of the machine at the third stage

2.4.4 Calculation of acceleration characteristics of the machine in the second and subsequent gears

2.5 Evaluation of crawler acceleration

3 Calculation of the motion of the tracked machine in the turn

3.1 Calculation of kinematic characteristics of track machine rotation

3.1.1 Determination of the radius of free rotation of the track machine

3.1.2 Determination of the minimum turning radius of the track machine

3.1.3 Calculation of the theoretical turning radii of the track machine

3.2 Calculation of dynamic characteristics of the track machine rotation

3.2.1 Determination of the rotation resistance coefficient

3.2.2 Determination of specific thrust force on running track

3.2.3 Calculation of specific force on lagging track

3.2.4 Calculation of specific thrust required for turning with "ideal" turning mechanism

3.2.5 Calculation of specific force of external resistance to rotation

3.3 Effect of tank drift on its average speed

3.4 Traction characteristic of the track machine taking into account curvilinear movement

CONCLUSION

BIBLIOGRAPHIC LIST

Introduction

In the course project, a number of tasks are solved: the maximum is determined

engine power, transmission range calculated, determined

maximum speed in each gear, traction is calculated

characteristics of the machine in each of the gears, and also the time is determined

acceleration and the path traveled by the car during acceleration.

Also, the upcoming exchange rate project will have to be calculated

motion of the track machine in turn, namely:

1. Define the range of possible steering radii of the track

machines, split it into several parts, determining 5 test points

possible turning radii;

2. Determine the coefficient of resistance to rotation and specific

traction forces on lagging and running caterpillars.

3. Calculate the effect of the tank drift on the average speed of its movement, graphically depict the construction of the speed limit function by drift.

As a result of the construction of traction characteristics of the tank and traction

machine rotation characteristics can be defined as minimum radius

turning of track machine at preset speed and gear. All

data required for operation are taken from the source data table, all

calculations are made in SI system.

Traction characteristic of the tracked machine taking into account curvilinear movement

The presence of the traction characteristic of the tank and the traction characteristic of the turn allows us to solve a number of practical problems:

- determination of speed and transmission number at which uniform rotation of the tank with a certain radius is possible;

- determination of the smallest possible radius of uniform rotation at a given speed and transmission under certain ground conditions;

To solve these problems, it is necessary to combine the two characteristics of the track machine in one drawing on a single scale. The characteristics are placed in drawing A1.

As a result of the construction of traction characteristics, it is possible to transfer the values ​ ​ of the specific thrust force of the engine to the traction characteristic of the rotation and determine the minimum radius of rotation of the track machine at a given speed and transmission. Conversely, knowing the radius of uniform rotation of the track machine, it is possible to determine the maximum possible speed of the machine along a given radius and the value of the included gear.

Conclusion

As a result of the course project, all the tasks assigned to determine the maximum engine power (it is 969779.53 W) were completed, the transmission range was calculated, the maximum speed in each gear was determined, the traction characteristic of the machine on each of the gears was calculated, and the acceleration time and path traveled by the car during acceleration (the acceleration time of the car is 66.95 seconds, the acceleration path is 891.1 meters). Graphs of power and torque, traction characteristics of the tracked machine, acceleration of the car and the path traveled during acceleration were built.

The characteristics of the motion of the tracked vehicle in rotation, the average value of the limitation of the speed of the vehicle along the drift of 8.28452 m/s, the effect of the tank drift on the average speed and transmission of the tracked vehicle are also determined.

Лист 2.cdw

Лист 1.cdw