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Working principle of slider crank mechanism ..etc
Slider Crank Mechanism for Demonstration and Experimentat
Crank Mechanism for Demonstration
Abstract
The slider-crank mechanism is a particular four-bar linkage configuration that exhibits both
linear and rotational motion simultaneously. This mechanism is frequently utilized in undergraduate
engineering courses to investigate machine kinematics and resulting dynamic forces. The position,
velocity, acceleration and shaking forces generated by a slider-crank mechanism during operation can
be determined analytically. Certain factors are often neglected from analytical calculations, causing
results to differ from experimental data. The study of these slight variances produces useful insight. The
following report details the successful design, fabrication and testing of a pneumatically powered slidercrank
mechanism for the purpose of classroom demonstration and experimentation. Transducers
mounted to the mechanism record kinematic and dynamic force data during operation, which can then
be compared to analytical values. The mechanism is capable of operating in balanced and unbalanced
configurations so that the magnitude of shaking forces can be compared. The engine was successfully
manufactured and operates as intended. Data recorded by the device s accelerometers is comparable to
calculated values of acceleration and shaking force
Slider Crank Mechanism for Demonstration and Experimentation
Page 3
Executive Summary
The slider-crank mechanism is a particular four-bar linkage configuration that converts linear
motion to rotational, or vice versa. Internal combustion engines are a common example of this
mechanism, where combustion in a cylinder creates pressure which drives a piston. The piston s linear
motion is converted into rotational motion at the crank through a mutual link, referred to as the
connecting rod. As the geometry of the crank forces the conversion of linear motion to rotational,
shaking forces are generated and applied to the crank s housing. These shaking forces result in
vibrations which impede the operation of the engine.
The slider-crank mechanism is frequently utilized in undergraduate engineering courses to
investigate machine kinematics and resulting dynamic forces. The position, velocity, acceleration and
shaking forces generated by a slider-crank mechanism during operation can be determined analytically.
Certain factors are often neglected from analytical calculations, causing results to differ from
experimental data. The assumption is frequently made that the crankshaft s angular velocity is constant.
In reality, angular velocity is slightly higher on the power stroke than the return stroke. The study of
these slight variances produces useful insight into the characteristics of piston driven engines.
The following report details the successful design, fabrication and testing of a pneumatically
powered slider-crank mechanism for the purpose of classroom demonstration and experimentation.
Complete analysis of the engine s kinematics was performed, assuming a constant angular acceleration..
Shaking forces of the unbalanced mechanism were calculated and balancing weights were designed for
statically and dynamically balanced configurations at the same constant angular velocity. Transducers
mounted to the mechanism were used to record kinematic and dynamic force data during operation,
which was then compared to the analytical values.
The engine was successfully manufactured and operates as intended. Data recorded by the
device s accelerometers is comparable to calculated values of acceleration and shaking force..
Satisfactory operation of the engine was achieved with minimal tuning. The engine is capable of
operating at angular velocities ranging from 80 to 330 RPM, using a balancing weight optimized for
200RPM. Sustained motion is achievable with cylinder pressures as low as 4.5psi, with a loss of only 2 psi
through the system. The reduction in shaking force achieved through use of the balance weights is
apparent both visually and in recorded data. All experimental values were reasonable when compared
with analytical calculations.
Posts: 49
Threads: 20
Joined: Aug 2009
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Slider Crank Mechanism for Demonstration and Experimentat
Crank Mechanism for Demonstration
Abstract
The slider-crank mechanism is a particular four-bar linkage configuration that exhibits both
linear and rotational motion simultaneously. This mechanism is frequently utilized in undergraduate
engineering courses to investigate machine kinematics and resulting dynamic forces. The position,
velocity, acceleration and shaking forces generated by a slider-crank mechanism during operation can
be determined analytically. Certain factors are often neglected from analytical calculations, causing
results to differ from experimental data. The study of these slight variances produces useful insight. The
following report details the successful design, fabrication and testing of a pneumatically powered slidercrank
mechanism for the purpose of classroom demonstration and experimentation. Transducers
mounted to the mechanism record kinematic and dynamic force data during operation, which can then
be compared to analytical values. The mechanism is capable of operating in balanced and unbalanced
configurations so that the magnitude of shaking forces can be compared. The engine was successfully
manufactured and operates as intended. Data recorded by the device s accelerometers is comparable to
calculated values of acceleration and shaking force
Slider Crank Mechanism for Demonstration and Experimentation
Page 3
Executive Summary
The slider-crank mechanism is a particular four-bar linkage configuration that converts linear
motion to rotational, or vice versa. Internal combustion engines are a common example of this
mechanism, where combustion in a cylinder creates pressure which drives a piston. The piston s linear
motion is converted into rotational motion at the crank through a mutual link, referred to as the
connecting rod. As the geometry of the crank forces the conversion of linear motion to rotational,
shaking forces are generated and applied to the crank s housing. These shaking forces result in
vibrations which impede the operation of the engine.
The slider-crank mechanism is frequently utilized in undergraduate engineering courses to
investigate machine kinematics and resulting dynamic forces. The position, velocity, acceleration and
shaking forces generated by a slider-crank mechanism during operation can be determined analytically.
Certain factors are often neglected from analytical calculations, causing results to differ from
experimental data. The assumption is frequently made that the crankshaft s angular velocity is constant.
In reality, angular velocity is slightly higher on the power stroke than the return stroke. The study of
these slight variances produces useful insight into the characteristics of piston driven engines.
The following report details the successful design, fabrication and testing of a pneumatically
powered slider-crank mechanism for the purpose of classroom demonstration and experimentation.
Complete analysis of the engine s kinematics was performed, assuming a constant angular acceleration..
Shaking forces of the unbalanced mechanism were calculated and balancing weights were designed for
statically and dynamically balanced configurations at the same constant angular velocity. Transducers
mounted to the mechanism were used to record kinematic and dynamic force data during operation,
which was then compared to the analytical values.
The engine was successfully manufactured and operates as intended. Data recorded by the
device s accelerometers is comparable to calculated values of acceleration and shaking force..
Satisfactory operation of the engine was achieved with minimal tuning. The engine is capable of
operating at angular velocities ranging from 80 to 330 RPM, using a balancing weight optimized for
200RPM. Sustained motion is achievable with cylinder pressures as low as 4.5psi, with a loss of only 2 psi
through the system. The reduction in shaking force achieved through use of the balance weights is
apparent both visually and in recorded data. All experimental values were reasonable when compared
with analytical calculations.
Posts: 59
Threads: 20
Joined: Jul 2009
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In this study, the kinematic and dynamic analysis of a modified slider crank mechanism which has an additional eccentric page link between connecting rod and crank pin, as distinct from a conventional mechanism, are presented. This new extra page link that may be called the eccentric connector transmits gas forces to the crank, and it also drives a planetary gear mechanism transmitting a great deal of driving forces to the output. In order to drive the planetary gear train, a pinion fixed to the eccentric connector is used. Consequently, the driving force is transmitted to crankshaft by means of two different ways. For the comparison, the dynamic analysis results of developed slider crank mechanism have been evaluated with respect to that of a conventional slider crank mechanism. As a result, although both the conventional and the modified slider crank mechanisms have the same stroke and the same gas pressure in the cylinder, it is observed that the modified mechanism has a bigger output torque than that of the conventional mechanism.The slider-crank mechanism is a particular four-bar linkage configuration that exhibits both
linear and rotational motion simultaneously. This mechanism is frequently utilized in undergraduate
engineering courses to investigate machine kinematics and resulting dynamic forces. The position,
velocity, acceleration and shaking forces generated by a slider-crank mechanism during operation can
be determined analytically. Certain factors are often neglected from analytical calculations, causing
results to differ from experimental data. The study of these slight variances produces useful insight. The
following report details the successful design, fabrication and testing of a pneumatically powered slidercrank
mechanism for the purpose of classroom demonstration and experimentation. Transducers
mounted to the mechanism record kinematic and dynamic force data during operation, which can then
be compared to analytical values. The mechanism is capable of operating in balanced and unbalanced
configurations so that the magnitude of shaking forces can be compared. The engine was successfully
manufactured and operates as intended. Data recorded by the device s accelerometers is comparable to
calculated values of acceleration and shaking force
Posts: 57
Threads: 26
Joined: Oct 2009
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0
Abstract
In this study, the kinematic and dynamic analysis of a modified slider crank mechanism which has an additional eccentric page link between connecting rod and crank pin, as distinct from a conventional mechanism, are presented. This new extra page link that may be called the eccentric connector transmits gas forces to the crank, and it also drives a planetary gear mechanism transmitting a great deal of driving forces to the output. In order to drive the planetary gear train, a pinion fixed to the eccentric connector is used. Consequently, the driving force is transmitted to crankshaft by means of two different ways. For the comparison, the dynamic analysis results of developed slider crank mechanism have been evaluated with respect to that of a conventional slider crank mechanism. As a result, although both the conventional and the modified slider crank mechanisms have the same stroke and the same gas pressure in the cylinder, it is observed that the modified mechanism has a bigger output torque than that of the conventional mechanism.
Posts: 48
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Joined: Jul 2009
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what is slider crank and dynamic analysis of slider crank mechanism. it should contain position,velocity, acceleration, angular acceleration, angular velocity, displacement.
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