P13471: UL Vibration Test Apparatus
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Detailed Design

Table of Contents

Analysis Documents

All analyses were completed in the documents below. The following sections will refer to these documents when referencing calculations.

Force Calculation.xlsx
SDI Appendix A - Theoretical Analysis.pdf

Design Overview

The rotational-to-linear mechanism operates in the horizontal plane with a the driving motor set below the system. A rugged baseplate provides support for the system.

Final Design

Final Design


The linear slider mechanism translates the rotational motion of the shaft through a connecting rod to a linear motion. It employs linear bearings guided by rails.
Linear Slider Notes

Linear Slider Notes

Linear Slider Model

Linear Slider Model

Linear Slider: Section View

Linear Slider: Section View


The adjustment mechanism is a friction locking device. Two bolts located on the upper slider clamp with two T-blocks located in the notched bed of the device. When torque is applied to the screws, the entire system is drawn together as the T-blocks come in contact with the upper groove. There are four major friction locking surfaces.
Adjustment Mechanism Notes

Adjustment Mechanism Notes

Adjustment Mechanism Model

Adjustment Mechanism Model

Adjustment Mechanism: Section View

Adjustment Mechanism: Section View

Adjustment Mechanism: Exploded View

Adjustment Mechanism: Exploded View


The connecting rod is the true medium between which rotational motion is converted to linear. It employs ball bearings that rotate about two press-fit pins, one located on the adjustment mechanism and the other located on the linear slider.
Connecting Rod Summary

Connecting Rod Summary


The recommended frame design significantly lowers the current system's size envelope. Additionally, a flange attachment region has been added for mounting improvement for the vertical conduit and luminaire.
Frame Notes

Frame Notes

Recommended Frame

Recommended Frame


Lubrication of the crankshaft system is much simplified from the scotch yoke design, which is the major reason for the move to the crankshaft style mechanism.
Lubrication Notes

Lubrication Notes

Kinematic Analysis of Crankshaft

Derivation of Velocity at B

Derivation of Velocity at B

Derivation of Acceleration at B

Derivation of Acceleration at B

Derivation of Velocity/Acceleration of Vertical Conduit

Derivation of Velocity/Acceleration of Vertical Conduit

Moment of Inertia Calculation

Moment of Inertia Calculation

Force Calculation

Force Calculation

Crankshaft/Connecting Rod

This analysis was adapted from Dr. Stephen Boedo's Single-Cylinder Engine Dynamic Analysis. Our analysis was a simplified form that treated the piston as a general linear slider and replaced any pressure forces on the piston with the 800lb force from the vertical conduit deflection.

FBD: Crankshaft System

FBD: Crankshaft System

Kinematic Relationships

Kinematic Relationships

Kinematic Equations

Kinematic Equations

FBD: Dynamic Equivalence

FBD: Dynamic Equivalence

Dynamic Equivalence Equations

Dynamic Equivalence Equations

Connecting Rod Moment of Inertia Analysis

Connecting Rod Moment of Inertia Analysis

FBD: Connecting Rod-Slider Mechanism

FBD: Connecting Rod-Slider Mechanism

Equilibrium Analysis/Bearing Loads and Lateral Slider Force

Equilibrium Analysis/Bearing Loads and Lateral Slider Force

Parameter Values

Parameter Values

Adjustment Mechanism

FBD: Adjustment Mechanism/Assumptions

FBD: Adjustment Mechanism/Assumptions

Adjustment Mechanism Analysis

Adjustment Mechanism Analysis


GFEM of the adjustment mechanism is shown below.
GFEM: Notes

GFEM: Notes

GFEM: Von-Mises on Bed

GFEM: Von-Mises on Bed

GFEM: Von-Mises on Upper

GFEM: Von-Mises on Upper

GFEM: Displacement

GFEM: Displacement

Drive Shaft Analysis

The recommended motor for this system outputs a 5/8" shaft diameter. Using variable diameter locking collars, the actual drive shaft of the system is chosen as 1" to aid in the robustness of the system. Two flange-type bearings mounted on either side of the system baseplate provide lateral support for the shaft. It is connected to the rotating disc and adjustment mechanism by a flange collar on the upper side of the baseplate. The shaft is keyed along its entire length.
Shear/Bending Moment/Torque Diagrams

Shear/Bending Moment/Torque Diagrams

Equilibrium Analysis/Marin Factor Calculations

Equilibrium Analysis/Marin Factor Calculations

Modified-Goodman Fatigue Strength Analysis

Modified-Goodman Fatigue Strength Analysis

Key Verification Analysis

Key Verification Analysis

Analysis of Miscellaneous Components

The threaded extension rod is the rigid connection between the slider mechanism and the vertical conduit. It is clamped to the slider in two places and is to be threaded into the collar located on the conduit to complete the connection.
Extension Rod Clamping Force/Buckling Verification

Extension Rod Clamping Force/Buckling Verification

The connecting rod is a simple rectangular design with ball bearings on either end. The entire part will be machined from one solid piece of steel and will be bolted together on either end to provide the force to keep the bearings in place. GFEM analysis of the component is shown below.

Connecting Rod Analysis

Connecting Rod Analysis


GFEM was completed on the connecting rod as shown below:
GFEM: Loading Cases

GFEM: Loading Cases

GFEM: Stress

GFEM: Stress

Bolt Strength Analysis

The system was designed in such a way that the bolts would be taking the majority of the load. This builds in a safety factor so that there is a better chance that, if failure were to occur, it would be the bolts that were the issue and not the more expensive and important machine components.

The following table details the major bolt locations in the system and their associated factors of safety. Note that the location of these calculations are denoted by section and page number as well as an equation number on that page. These locations are to be found in Appendix A, a PDF of which can be found at the top of this page.

Bolt Analysis Summary

Bolt Analysis Summary

Linear Slider Bolt Analysis

Linear Slider Bolt Analysis

Shaft Bearing/Pin Block Analysis

Shaft Bearing/Pin Block Analysis

Adjustment Mechanism Bed/Shaft-Disc Flange Analysis

Adjustment Mechanism Bed/Shaft-Disc Flange Analysis

Motor Selection

Following Customer Need CN3, the desired motor was to be a 3-phase, 240V AC motor. Analysis was completed on the system at steady state, yielding a maximum required horsepower of 0.41HP. A 1HP motor was then decided upon. A start-up period analysis followed, where the inertia of the system was included. Assuming under a minute start-up to 2000RPM, a motor torque was calculated and referenced to the Reliance Electric torque-speed curve. The recommended motor was chosen from Baldor and is also shown below.
Steady State/Start-up Torque Analysis

Steady State/Start-up Torque Analysis

Reliance Electric Torque-Speed Curve

Reliance Electric Torque-Speed Curve

Torque-Speed Curve Notes

Torque-Speed Curve Notes

Recommended Motor

Recommended Motor

References

References

References

Bill of Material (BOM)

BOM: Hardware

BOM: Hardware

BOM: Raw Materials

BOM: Raw Materials

BOM: Frame Components

BOM: Frame Components

BOM: Test Apparatus

BOM: Test Apparatus

BOM: Motor Components

BOM: Motor Components

BOM: Overall

BOM: Overall

Test Plans

The testing of this system will consist only of verifying the displacement (or stroke) of the crankshaft mechanism. A dial gauge will be used for measurement purposes. The adjustment mechanism will allow for fine-tuning of the system if the initial displacement is not exact.
Test Plan

Test Plan

Risk Assessment

The below assessment has been updated to reflected actions taked since the System Design Review to mitigate risk. Additionally, new risk areas have developed.
Updated Risk Assessment

Updated Risk Assessment

Senior Design II Preliminary Schedule

Schedule: Weeks 1-5

Schedule: Weeks 1-5

Schedule: Weeks 6-11

Schedule: Weeks 6-11

Detailed Design Review

Detailed Design Review to be completed at Cooper in Syracuse on Thursday, February 21, 2013 at 11:30am.

Presentation: MSD Design Review Presentation.pptx MSD Design Review Presentation.pdf

Full transcript of this meeting to follow.

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