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http://www.iaeme.com/IJMET/index.asp 202 [email protected]
International Journal of Mechanical Engineering and Technology (IJMET) Volume 6, Issue 11, Nov 2015, pp. 202-212, Article ID: IJMET_06_11_023
Available online at
http://www.iaeme.com/IJMET/issues.asp?JTypeIJMET&VType=6&IType=11
ISSN Print: 0976-6340 and ISSN Online: 0976-6359
© IAEME Publication
ANALYSIS OF SPACE FRAME OF
FORMULA SAE AT HIGH SPEED WITH
ERGONOMIC AND VIBRATIONAL
FACTORS
Akash Sood
School of Energy & Environment Management,
Rajiv Gandhi Proudyogiki Vishwavidyalaya,
Bhopal (Madhya Pradesh), India
Padam Singh
Scientist-F, Former Director,
Ministry of New and Renewable Energy, Government of India
ABSTRACT
This paper introduces a design and analysis methodology of space frame
chassis in the context of ending new and innovative design principle by means
of optimization techniques. The design is according to the Formula SAE
International rule book. Our paper emphasis on the driver safety, ergonomics
of the driver according to the rule book in which we calculate the critical
conditions of the race track, emphasis on the vehicle head on collision, rear
impact test, torsional rigidity test, vibrational analysis of roll cage (space
frame chassis) and side impact to make that chassis under the design limits
and having the factor of safety 1-2.5 having a material of chromoly 4130
which is selected as an optimum material for design.
Key words: Formula SAE, Space Frame, Roll Cage, Chassis, Crash Analysis.
Cite this Article: Sood, A. and Singh, P. Analysis of Space Frame of Formula
SAEat High Speed with Ergonomic and Vibrational Factors. International
Journal of Mechanical Engineering and Technology, 6(11), 2015, pp. 202-212.
http://www.iaeme.com/currentissue.asp?JType=IJMET&VType=6&IType=11
1. INTRODUCTION
Traditionally engineering has normally been performed by teams, each with expertise
in a specific discipline, such as aerodynamics or structures. Each team would use its
member’s experience and judgment to develop a workable design, usually
sequentially. For example, the aerodynamics experts would outline the shape of the
body, and the structural experts would be expected to fit their design within the shape
specified. The goals of the teams were generally performance-related, such as
Analysis of Space Frame of Formula SAE at High Speed with Ergonomic and
Vibrational Factors
http://www.iaeme.com/IJMET/index.asp 203 [email protected]
maximum speed, minimum drag, or minimum structural weight. This paper is devoted
to the structural design of a formula student vehicle which persist the optimal number
of members, minimum weight and optimum design strength under the critical
conditions of track.
2.PROBLEM DESCRIPTION
2A. Terminology and definitions
S.No. Terminology Symbol Definition Unit
1 Stress σ
The nature of forces set up within a
body to balance the effect of the
externally applied forces
Pa
2 Strain ε Ratio of deformed dimension by
original dimension.
Dimensio
nless
3 SAE SAE Society of Automotive Engineers -
4 Formula SAE F-SAE Formula – Society of Automotive
Engineers -
5 Kilo metre per
hour kmph A measure of speed -
6 Delta ∆ A Greek symbol denoting change -
Standards Relevant to Formula SAE
J183 – Engine Oil Performance and Engine Service Classification – Standard
J306 – Automotive Gear Lubricant Viscosity Classification – Standard
J429 – Mechanical and Material Requirements for Externally Threaded Fasteners –
Standard
J452 - General Information – Chemical Compositions, Mechanical and Physical
Properties of SAE Aluminum Casting Alloys - Information Report
J512 – Automotive Tube Fittings – Standard
J517 – Hydraulic Hose – Standard
J637 – Automotive V-Belt Drives – Recommended Practice
J829 – Fuel Tank Filler Cap and Cap Retainer
J1153 - Hydraulic Cylinders for Motor Vehicle Brakes – Test Procedure
J1154 – Hydraulic Master Cylinders for Motor Vehicle Brakes - Performance
Requirements – Standard
J1703 - Motor Vehicle Brake Fluid – Standard
J2045 – Performance Requirements for Fuel System Tubing Assemblies – Standard
J2053 – Brake Master Cylinder Plastic Reservoir Assembly for Road Vehicles –
Standard
The purpose of the frame is to rigidly connect the front and rear suspension while
providing attachment points for the different systems of the car. It provides dynamic
stability, strength, strength against vertical bending, and safety of driver against
accidents and also acts as a vibration harness agent[1]. Race cars that run on a high
speed (about 100-150kmph) by the virtue of that the chassis design must be capable of
sustaining all the critical conditions of track (like Crash impact & Vibrational
resonance) to justify our design induced stresses under critical conditions has to lie
under the stress limits, able to accommodate driver and must be designed according to
norms followed by F-SAE [2]. (Assumed weight of vehicle is 2450 N).
http://www.iaeme.com/IJMET
2B. Material Properties
In this context the material grade is AISI 4130 steel annealed at
of material is offered by manufacturer to release the internal compressive stress of the
pipes to increase the compressive load carrying capacity
equivalent yield and ultimate tensile strength the same cross
the baseline tubing is maintained
pipe thickness of 3mm is taken for the design and modelling of space frame.
2C. Orthographic and Isometric Views
Orthographic views and isometric view is tabulated below to completely
space frame.
While designing the space frame a keynote is considered that every member is
triangulated to increase the strength of chassis, the proper method of triangulation is
explained in figure 2.
AkashSood and Padam Singh
IJMET/index.asp 204
Material Properties
In this context the material grade is AISI 4130 steel annealed at 850ºC, the annealing
of material is offered by manufacturer to release the internal compressive stress of the
pipes to increase the compressive load carrying capacity[3]. To maintain the
equivalent yield and ultimate tensile strength the same cross-sectional area of steel as
the baseline tubing is maintained [2]. The outer diameter of the pipe is 25.4 mm and
mm is taken for the design and modelling of space frame.
Table 1
Orthographic and Isometric Views
views and isometric view is tabulated below to completely
Figure 2C(a): Views of space frame
While designing the space frame a keynote is considered that every member is
triangulated to increase the strength of chassis, the proper method of triangulation is
850ºC, the annealing
of material is offered by manufacturer to release the internal compressive stress of the
. To maintain the
sectional area of steel as
. The outer diameter of the pipe is 25.4 mm and
mm is taken for the design and modelling of space frame.
views and isometric view is tabulated below to completely visualize the
While designing the space frame a keynote is considered that every member is
triangulated to increase the strength of chassis, the proper method of triangulation is
Analysis of Space Frame of Formula SAE at High Speed with Ergonomic and
http://www.iaeme.com/IJMET
Figure 2B(b)
3. DESIGN IMPLEMENTATIO
3A. Ergonomics testing of Driver sitting position
Figure 3A(a)
Figure 3A(b)
In figure (4) The driver sitting position is in booster reclined position and
according to Brian Peaco
position of sitting in high speed racing vehicles. Properly incorporating the driver into
a FSAE frame design can be very difficul
Each driver interface has to be designed so that it is comfortable for a wide variety of
drivers [5]. By considering various SAE standards like H
line and cross examined by setting a SAE 2D template of 95 percentile male. It is
perfectly acceptable for 95 percentile male. Head contour, eyellipse and seat
movement envelop along with foot angle of 87
accelerator and brake paddle by considering heel point at the depressed floor covering
[6].
Frame of Formula SAE at High Speed with Ergonomic and
Vibrational Factors
IJMET/index.asp 205
Figure 2B(b) Condition of proper triangulation[2]
DESIGN IMPLEMENTATION
Ergonomics testing of Driver sitting position
Figure 3A(a) 2D-Template of 95 percentile male[2]
Figure 3A(b) Manikin simulation for driver ergonomics
In figure (4) The driver sitting position is in booster reclined position and
according to Brian Peacock and Waldemar Karwowski[4], it is the most suitable
position of sitting in high speed racing vehicles. Properly incorporating the driver into
a FSAE frame design can be very difficult because of wide variations in driver sizes.
Each driver interface has to be designed so that it is comfortable for a wide variety of
. By considering various SAE standards like H-point, torso
line and cross examined by setting a SAE 2D template of 95 percentile male. It is
perfectly acceptable for 95 percentile male. Head contour, eyellipse and seat
movement envelop along with foot angle of 87º is taken at the time of un
accelerator and brake paddle by considering heel point at the depressed floor covering
Frame of Formula SAE at High Speed with Ergonomic and
In figure (4) The driver sitting position is in booster reclined position and
, it is the most suitable
position of sitting in high speed racing vehicles. Properly incorporating the driver into
t because of wide variations in driver sizes.
Each driver interface has to be designed so that it is comfortable for a wide variety of
point, torso line, and thigh
line and cross examined by setting a SAE 2D template of 95 percentile male. It is
perfectly acceptable for 95 percentile male. Head contour, eyellipse and seat
is taken at the time of un-pressed
accelerator and brake paddle by considering heel point at the depressed floor covering
http://www.iaeme.com/IJMET
Figure 3A(c)
In figure (5) the driver visual approach distance does not interfere more than 1.987
meter from front wheel that’s why we can say that the
optimal level. Computer Aided Design (CAD) tool with digital human models are
available to be used in the ergonomics design process. These human models can be
configured to represent people of various shapes and sizes in m
so represent the intended user group for any vehicle, in this paper we use CATIA V5
for analyzing the driver sitting position
The multi tubular space frame of formula SAE vehicle should be capable of
enduring harsh and high end corner at the time of track run
space frame was done using SolidWorks
various critical conditions of track like front impact, side impact, and rear impact,
torsional and vibrational criterion. The main focus of designing the space frame is
drier safety thus the results
the design wherever necessary
3B. Front Impact Analysis:
As we consider that our vehicle is in static condition and rear side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
mass hits our vehicle at a speed of 145 kmph.
Figure 3B(a): Before impact
Condition of inelastic collision:
F=Mass x Acceleration
Acceleration = ��
��
Velocity before impact = 145 kmph = 40.277 m/s
Velocity after impact = 0 m/s
Time of impact = 200 mSec. = 0.2
Acceleration (a) = (40.277
= 201.385 m/s2
F = 250 x 201.385
= 50346.25 newton ≈ 50000 N
By applying load to the front members equally by fixing the rear members of the
chassis, the following results were analyzed.
AkashSood and Padam Singh
IJMET/index.asp 206
Figure 3A(c) Visual interference detection
In figure (5) the driver visual approach distance does not interfere more than 1.987
meter from front wheel that’s why we can say that the driver visual hindrance is at its
optimal level. Computer Aided Design (CAD) tool with digital human models are
available to be used in the ergonomics design process. These human models can be
configured to represent people of various shapes and sizes in many populations, and
so represent the intended user group for any vehicle, in this paper we use CATIA V5
for analyzing the driver sitting position [6].
The multi tubular space frame of formula SAE vehicle should be capable of
enduring harsh and high end corner at the time of track run [7]. The FEA analysis of
using SolidWorks-2013. The space frame was analyzed for
various critical conditions of track like front impact, side impact, and rear impact,
torsional and vibrational criterion. The main focus of designing the space frame is
drier safety thus the results were studied and necessary changes were incorporated in
the design wherever necessary [8].
nt Impact Analysis:
As we consider that our vehicle is in static condition and rear side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
mass hits our vehicle at a speed of 145 kmph.
Before impact Figure 3B(b): After impact
Condition of inelastic collision: by using the formula
Velocity before impact = 145 kmph = 40.277 m/s
Velocity after impact = 0 m/s
Time of impact = 200 mSec. = 0.2 Sec.
Acceleration (a) = (40.277-0)/0.2
50000 N
By applying load to the front members equally by fixing the rear members of the
chassis, the following results were analyzed.
In figure (5) the driver visual approach distance does not interfere more than 1.987
driver visual hindrance is at its
optimal level. Computer Aided Design (CAD) tool with digital human models are
available to be used in the ergonomics design process. These human models can be
any populations, and
so represent the intended user group for any vehicle, in this paper we use CATIA V5
The multi tubular space frame of formula SAE vehicle should be capable of
. The FEA analysis of
2013. The space frame was analyzed for
various critical conditions of track like front impact, side impact, and rear impact,
torsional and vibrational criterion. The main focus of designing the space frame is
were studied and necessary changes were incorporated in
As we consider that our vehicle is in static condition and rear side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
After impact
By applying load to the front members equally by fixing the rear members of the
Analysis of Space Frame of Formula SAE at High Speed with Ergonomic and
http://www.iaeme.com/IJMET
Figure 3B(c)
3C. Rear Impact Test:
As we consider that our vehicle is in static condition and Front side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
mass hits our vehicle at a speed of 145 kmph.
Condition of inelastic collision:
F=Mass x Acceleration
Acceleration = ��
��
Velocity before impact = 145 kmph =40.277 m/s
Velocity after impact = 0 m/s
Time of impact = 200 mSec. = 0.2 Sec.
Acceleration (a) = (40.277
= 201.385 m/s2
F = 250 x 201.385
= 50346.25 newton ≈ 50000 N
Applying load to the rear members equally by fixing the front of the chassis the
following results were analyzed.
Figure 3C(a):
Frame of Formula SAE at High Speed with Ergonomic and
Vibrational Factors
IJMET/index.asp 207
Figure 3B(c) FEA of front impact test
Table 2
As we consider that our vehicle is in static condition and Front side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
hits our vehicle at a speed of 145 kmph.
Condition of inelastic collision: by using the formula
Velocity before impact = 145 kmph =40.277 m/s
Velocity after impact = 0 m/s
Time of impact = 200 mSec. = 0.2 Sec.
cceleration (a) = (40.277-0)/0.2
50000 N
Applying load to the rear members equally by fixing the front of the chassis the
following results were analyzed.
Figure 3C(a): FEA analysis of rear impact test
Frame of Formula SAE at High Speed with Ergonomic and
As we consider that our vehicle is in static condition and Front side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
Applying load to the rear members equally by fixing the front of the chassis the
http://www.iaeme.com/IJMET
3D. Side Impact Test
As we consider that our vehicle is in static condition and right side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
mass hits our vehicle at a speed of 100 kmph.
Condition of inelastic collision
F=Mass x Acceleration
Acceleration = ��
��
Velocity before impact = 100 kmph = 27.77 m/s
Velocity after impact = 0 m/s
Time of impact = 200 mSec. = 0.2 Sec.
Acceleration (a) = (27.77-
= 138.85 m/s2
F= 250 x 138.85
= 34712 newton ≈ 35000 N
By applying force to side members equally, and fixing the other side of the chassis.
Figure 3D(c):
AkashSood and Padam Singh
IJMET/index.asp 208
Table 3
As we consider that our vehicle is in static condition and right side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
at a speed of 100 kmph.
Figure 3D(a): Before impact
Figure 3D(b): After impact
Condition of inelastic collision: by using the formula
Velocity before impact = 100 kmph = 27.77 m/s
m/s
Time of impact = 200 mSec. = 0.2 Sec.
-0)/0.2
35000 N
By applying force to side members equally, and fixing the other side of the chassis.
Figure 3D(c): FEA analysis of side impact test
As we consider that our vehicle is in static condition and right side of the vehicle is in
contact with a rigid wall and at that instant of time another vehicle having the same
By applying force to side members equally, and fixing the other side of the chassis.
Analysis of Space Frame of Formula SAE at High Speed with Ergonomic and
http://www.iaeme.com/IJMET
3E. Front Torsion Test
Assuming that our vehicle front wheel will go on bump and considering the critical
condition of dynamic loading under the front wishbone member in the space frame,
by the reason of this we a
wishbone supporting members i.e. 4000 N on each side or in other words we can say
that assuming the whole mass of the vehicle at one wheel
Figure 3E(a):
Figure 3E(b):
3F. Rear Torsion Test
Assuming that our vehicle’s rear wheel will go on bump and considering the critical
condition of dynamic loading under the rear wishbone member in the space frame. By
the reason of this we apply approximately double load of vehicle on the front
wishbone supporting members i.e. 4000 N on each side.
Frame of Formula SAE at High Speed with Ergonomic and
Vibrational Factors
IJMET/index.asp 209
Table 4
Front Torsion Test
Assuming that our vehicle front wheel will go on bump and considering the critical
condition of dynamic loading under the front wishbone member in the space frame,
by the reason of this we apply approximately double load of vehicle on the front
wishbone supporting members i.e. 4000 N on each side or in other words we can say
that assuming the whole mass of the vehicle at one wheel [9], [10].
Figure 3E(a): Condition of front torsional test
Figure 3E(b): FEA analysis of front torsion test
Table 5
Assuming that our vehicle’s rear wheel will go on bump and considering the critical
condition of dynamic loading under the rear wishbone member in the space frame. By
this we apply approximately double load of vehicle on the front
wishbone supporting members i.e. 4000 N on each side.
Frame of Formula SAE at High Speed with Ergonomic and
Assuming that our vehicle front wheel will go on bump and considering the critical
condition of dynamic loading under the front wishbone member in the space frame,
pply approximately double load of vehicle on the front
wishbone supporting members i.e. 4000 N on each side or in other words we can say
Assuming that our vehicle’s rear wheel will go on bump and considering the critical
condition of dynamic loading under the rear wishbone member in the space frame. By
this we apply approximately double load of vehicle on the front
http://www.iaeme.com/IJMET
Figure 3
Figure
3G. Vibrational Analysis
Finding the natural frequency & mode shapes of the chassis by fixing the wishbone
supporting member’s acting under the effect of gravity
acceleration though we are able to get more precise values of vibrations, although
their simultaneous periods are also determined for examining the correct vibrational
behavior[11]–[14].
Figure 3G(a): First mode
AkashSood and Padam Singh
IJMET/index.asp 210
Figure 3F(a) Condition of rear torsional test
Figure 3F(b) FEA analysis of rear torsion test
Table 6
Vibrational Analysis
Finding the natural frequency & mode shapes of the chassis by fixing the wishbone
supporting member’s acting under the effect of gravity[4]. By taking the gravitational
acceleration though we are able to get more precise values of vibrations, although
their simultaneous periods are also determined for examining the correct vibrational
First mode Figure 3G(b): Second mode
Finding the natural frequency & mode shapes of the chassis by fixing the wishbone
. By taking the gravitational
acceleration though we are able to get more precise values of vibrations, although
their simultaneous periods are also determined for examining the correct vibrational
Second mode
Analysis of Space Frame of Formula SAE at High Speed with Ergonomic and
http://www.iaeme.com/IJMET
Figure 3G(c): Third mode
Graph 1
4. CONCLUSION
All the FOS is greater than 1 and satisfies all the F
designing the space frame, triangulations are provided to increase the strength of
space frame and to reduce the degree of freedom of chassis to make chassis stiff.
While analysing the vibrational modes of space frame we get the freq
Hz which is way beyond the natural frequency of engine 13.89 Hz to 24.54 Hz
(laboratory tested parameter) and suspension system, hence the designed space frame
is safe under the all critical conditions of the track and ready to be manufactu
REFERENCES
[1] P. Kapadiya, V. Bavisi, and D. Nair, “Design and analysis of roll cage 1 1,2,3,” no.
03, pp. 741–744, 2015.
[2] F. R. Committee, “2013 Formula SAE ® Rules Table of Contents,” p. 176, 2015.
[3] B. Cantor, G. Patrick, and J. Colin,
Functional, and Novel Materials
[4] W. Karwowski and B. Peacock,
[5] E. F. Gaffney III and A. R. Salinas, “Introduction to Form
and Frame Design,”
[6] N. Gkikas, Automotive Ergonomics: Driver
[7] S. Barbat, X. Li, P. Prasad, A. Engineering, F. M. Company, and U. States,
Frame of Formula SAE at High Speed with Ergonomic and
Vibrational Factors
IJMET/index.asp 211
Third mode Figure 3G(d): Fourth mode
Figure 3G(e): Fifth mode
Table
All the FOS is greater than 1 and satisfies all the F-SAE rules and guidelines. While
designing the space frame, triangulations are provided to increase the strength of
space frame and to reduce the degree of freedom of chassis to make chassis stiff.
While analysing the vibrational modes of space frame we get the frequency of 28.172
Hz which is way beyond the natural frequency of engine 13.89 Hz to 24.54 Hz
(laboratory tested parameter) and suspension system, hence the designed space frame
is safe under the all critical conditions of the track and ready to be manufactu
P. Kapadiya, V. Bavisi, and D. Nair, “Design and analysis of roll cage 1 1,2,3,” no.
744, 2015.
F. R. Committee, “2013 Formula SAE ® Rules Table of Contents,” p. 176, 2015.
B. Cantor, G. Patrick, and J. Colin, Automotive Engineering Lightweight,
Functional, and Novel Materials. 2008.
W. Karwowski and B. Peacock, Automotive Ergonomics. Taylor & Francis, 1993.
E. F. Gaffney III and A. R. Salinas, “Introduction to Formula SAE ® Suspension
and Frame Design,” SAE Int. - Tech. Pap., no. Paper Number: 971584, 2007.
Automotive Ergonomics: Driver-Vehicle Interaction. CRC Press, 2013.
S. Barbat, X. Li, P. Prasad, A. Engineering, F. M. Company, and U. States,
Frame of Formula SAE at High Speed with Ergonomic and
Fourth mode
Table 7
and guidelines. While
designing the space frame, triangulations are provided to increase the strength of
space frame and to reduce the degree of freedom of chassis to make chassis stiff.
uency of 28.172
Hz which is way beyond the natural frequency of engine 13.89 Hz to 24.54 Hz
(laboratory tested parameter) and suspension system, hence the designed space frame
is safe under the all critical conditions of the track and ready to be manufactured.
P. Kapadiya, V. Bavisi, and D. Nair, “Design and analysis of roll cage 1 1,2,3,” no.
F. R. Committee, “2013 Formula SAE ® Rules Table of Contents,” p. 176, 2015.
Automotive Engineering Lightweight,
. Taylor & Francis, 1993.
ula SAE ® Suspension
, no. Paper Number: 971584, 2007.
. CRC Press, 2013.
S. Barbat, X. Li, P. Prasad, A. Engineering, F. M. Company, and U. States,
AkashSood and Padam Singh
http://www.iaeme.com/IJMET/index.asp 212 [email protected]
“Vehicle-to-vehicle front-to-side crash analysis using a CAE based methodology,”
pp. 1–8.
[8] R. G. Dominy, “Sports Prototype Race Car Optimization,” Proc. 2002 SAE Mot.
Eng. Conf. Exhib., no. 724, 2002.
[9] W. F. Milliken and D. L. Milliken, Race Car Vehicle Dynamics, vol. 1. 1995.
[10] F. F. Ling, Fracture Mechanics. 2006.
[11] A. Goyal, M. Singh, and S. Sharma, “Free Vibration Mode Shape Analysis And
Fabrication Of The Roll Cage For All-Terrain Vehicle Based On FEA,” Int. J. Sci.
Technol. Res., vol. 3, no. 6, pp. 228–231, 2014.
[12] S. Dheivarayan and S. Gouthaman, “Reduction of seat vibration in an ATV through
design Modification,” no. June, pp. 3–7, 2015.
[13] M. Harrison, Vehicule Refinement, Controlling Noise and Vibration in Road
Vehicles. 2004.
[14] W. Pawlus, J. E. Nielsen, H. R. Karimi, and K. G. Robbersmyr, “Mathematical
Modeling and Analysis of a Vehicle Crash,” in Proceedings of the 4th European
Computing Conference, 2009, vol. 4, pp. 194–199.