Senior Design Presentation

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John Deere Roll Over

Protection System Upgrades

Final Report

Chris Henningsen, Drew Hilgers , Travis McDonald, Michael

Thiele, Ben Klemp, Jon Zickermann

Current Setup

• Roll Over Protection

Structure (ROPS) test:

tests to user safety

during a rollover

– Tests the cage used by

forestry equipment

• Built in 1971

– Fixture has been

reinforced and updated

since thenFig 1: Current Fixture

Photo Courtesy of John Deere

Current Setup

• History of load requirements

– 1990: 50,000 lbf

– 2003: 62,080 lbf

– 2006: 71,165 lbf

– 2013: 178,842 lbf

• ROPS test includes:

– Side Push

– Vertical Crush

– Longitudinal PushFig 2: Cab after 3 Tests

Current Setup

• Problems

– Large quantity of time wasted between tests

– Will not be able to handle future tests

Fig 3: ROPS test at a different facility

Project

• Scope of project

– Determine designs needed to overcome current problems

– Consider design alternatives to improve the fixture

– Design new test fixture• Solid Models

• Finite Element Analysis

New Fixture

• Goals

– Ability to adjust cylinders horizontally and vertically.

– Design such that the test specimen can be located once, not moved for each test.

– Ability to move cylinders from the ground.

– 2 push blocks perpendicular to each other

Fig 4: Sample John Deere Forestry Equipment

New Fixture

Push Block

Base Plate Area

15x15

Push Block

10’

10’

Pu

sh

B

lo

ck

Pu

sh

B

lo

ck

Proposed Setup – Top View

Ability to lock cylinder mount and cross beam mount without climbing a ladder

350,000 lbf

100,000lbf

New FixtureProposed Setup – Side View

Cab

Frame

Load Cylinder

Force = 350,000 lbf

15’

Objectives Tree

Objectives

Criteria Weight

Free Standing 16.50%

Fast setup time between tests 16.75%

Accommodating to different sized products 16.75%

Safe 25.00%

Manufacturable in-house 11.25%

Minimal Floor Area 3.75%

Durable 10.00%

Total 100%

Objectives

FAF – Pre Usage

Outputs: Test results from the side push, top crush and front push tests

FAF – Usage

FAF – Post Usage

Objective Specification Target

Free Standing Self SupportingMust be self supporting

Fast Setup Time between tests

# Tools Required for set-up

less than 5

# adjustments required for set-up

less than 6

time required to adjustment

1 day or less to run all 3 tests

Accommodating to different sized

productsLoad Range max load= 350,000 lbf

Minimal Floor Area Spacing 15 ft tall

Safe Alignmentperpendicular and level with cab

Manufacturable in-house

Steel thickness 5 in max

Manufacturing processes

keep to cutting and welding

Durable Factor of Safety at least 1.6

House of Quality

Quality

Characteristics

(a.k.a. "Functional

Requirements" or

"How s")

Demanded Quality

(a.k.a. "Customer

Requirements" or

"Whats") 0 1 2 3 4 5

1 9 16.5 16.5 5 0

2 9 16.8 16.8 5 2

3 9 16.8 16.8 5 3

4 9 25.0 25.0 4 3

5 9 11.3 11.3 5 5

6 9 3.8 3.8 3 4

7 9 10.0 10.0 5 4

8

9

10

Max R

ela

tio

nsh

ip V

alu

e in

Ro

w

Θ Ο

Free Standing

Ο

Max Relationship Value in Column

Target or Limit Value

Weight / Importance

6.8 12.2 Relative Weight

Difficulty

(0=Easy to Accomplish, 10=Extremely Diff icult)

Ο Ο

Θ Θ

# T

ools

Required for

set-

up

# a

dju

stm

ents

required for

set-

up

time r

equired to a

dju

stm

ent

Load R

ange

Spacin

g

Alig

nm

ent

Ste

el t

hic

kness

Ο Θ Ο

Θ Θ

9

315.0

at le

ast 1.6

Accommodating to different sized products

Safe

Manufacturable in-house

Minimal Floor Area

Fast Setup Time betw een tests

Θ

Θ Θ Θ

Durable

Θ Ο

Θ

14.2

9 99

6.8 10.2 11.5

150.8 271.8 300.0

9

142.5150.8 150.8 225.8 255.8

9 99 9

x x

Facto

r of S

afe

ty

Yes

9

257.3

Θ

Θ

Ο

Ro

w #

Direction of Improvement:

Minimize (▼), Maximize (▲), or Target (x)

Self

Support

ing

Weig

ht

/ Im

po

rtan

ce

11 12 13 14 15

Rela

tive W

eig

ht

▼ ▼ ▼ ▲

5 6 7 8 9 10

x x

Manufa

ctu

ring p

rocesses

x

Column # 1 2 3 4

┼┼ ▼ ┼┼ ┼ ┼

┼ ┼▼

┼ ┼┼ ┼

┼ ┼┼

┼ ┼

┼ ▬

┼┼ ▬

┼┼

3Moderate Relationship

Competitive Analysis

(0=Worst, 5=Best)

▲ 1

┼┼

Weak Relationship

Strong Positive Correlation

Objective Is To Hit Target

Objective Is To Maximize

Positive Correlation┼

Negative Correlation▬

Strong Negative Correlation

▼ Objective Is To Minimize

Ο

Powered by QFD Online (http://www.QFDOnline.com)

Our

Com

pany

Exis

ting F

ixtu

re

Com

petit

or

2

Com

petit

or

3

Com

petit

or

4

Com

petit

or

5

15ft tall

13.5 6.46.8

less than 6

less than 1

day for

all

3 tests

350000 lb

s

Perp

endic

ula

r to

cab

11.6

x

less than 5

" th

ick

restr

ict to

cuttin

g a

nd

weld

ing

less than 5

Title:

Author:

Date:

Notes:

Team 9

Legend

Θ Strong Relationship 9

ROPS House of Quality

Our Company

Existing Fixture

Competitor 2

Competitor 3

Competitor 4

Competitor 5

Advanced Decision Matrix

3-D Layout of Fixture

Design

• Hand calculations done to find starting member sizes

• Basic frame designed using Autodesk Multiphysics using beam elements

• Solid model designed from frame

– Tested with ANSYS workbench

• Results interpreted and frame redesigned

– Repeated

Design

Design Material

Beams: Grade 55 High Strength Low Alloy Steel

• Yield Strength: 55 ksi

• Factor of Safety: 1.6

• Design Stress: 34.4 ksi

Design Hand Calculations

Base Design in Autodesk Multiphysics

Design3-D Layout of Fixture

350,000 lbf Center Push

100,000 lbf Center Push

Pull Down Test

Design

• Mix of brick and tetrahedron elements

– Body and face sizing used to reduce the quantity of elements

• Floor modeled as a elastic support with a large spring constant

• One beam fixed to improve the quality of the analysis

ANSYS Simulation Notes

Final ANSYS Simulation – Mesh

Design

ANSYS Simulation – Setup

Design

1st ANSYS Simulation, von Mises Stress

Design

1st ANSYS Simulation, Normal Stress

Design

1st ANSYS Simulation, Deformation

Design

Design

2nd ANSYS Simulation, vonMises

Design

2nd ANSYS Simulation, Normal Stress

Design

2nd ANSYS Simulation, Deformation

Design

2nd ANSYS Simulation, Fatigue Analysis

Design

3rd ANSYS Simulation, vonMises

Design

3rd ANSYS Simulation, Normal Stress

Design

3rd ANSYS Simulation, Deformation

Design

• Placing the 350,000 lbf load at the edge resulted in the highest stress and shortest life (~284 cycles)

• Positioning the cylinders at the center of the beams result in lower stress and deflection compared to the edge

ANSYS Simulation Notes

Analysis of Welded

Connections

Analysis of Welded Connections

• Load And Resistance Factor Design (LRFD)

– ½ inch weld size

– E70XX Electrode

– Available strength =0.75R

Analysis of Welded

Connections

• W14X233 Member

– Able to withstand 452.4 kip of force at each joint

• W12X87 Member

– Able to withstand 242.6 kip of force at each joint

Final Frame Assembly

Guide Mounts

Adjustments

Final Design

Recommendations

• Reuse the existing floor plate

• Remote engaged clamping mechanism

Conclusions

Achievements:

• Adjustability

• Sustain maximum forces

• Decreased setup time

• No repositioning of cab

QUESTIONS?