Up-Scaling and Optimisation of Fire Fighting Ground Vehicle Track System.
Applied Mechanics and Materials Vol. 315 (2013) pp 236-240
© (2013) Trans Tech Publications, Switzerland
doi:10.4028/www.scientific.net/AMM.315.236
Up-Scaling and Optimisation of Fire Fighting Ground Vehicle Track
System
CheeFai Tan1, a, Ranjit Singh Sarban Singh2, V.K. Kher1 and H.F. Kong1
1
Integrated Design Research Group (IDEA),Faculty of Mechanical Engineering,
Universiti Teknikal Malaysia Melaka (UTeM), Melaka, Malaysia
2
Faculty of Electronic and Computer Engineering, Universiti Teknikal Malaysia Melaka (UTeM),
Melaka, Malaysia
a
cheefai@utem.edu.my
Keywords: Fire fighting machine; Track system; Absorber; Up-scaling and optimisation
Abstract. Current UTeM’s fire fighting machine is developed to operate indoor only. It is not
efficient when it is operating on rocky surfaces (outdoor) as it faces the problem of shock and
vibration reduction. The track system of the machine cannot move smoothly because the rollers are
fixed to the chassis. This paper describes the method of up-scaling and optimising the track system
for the current fire fighting machine. The new track system concept is firstly developed by using
Computer-Aided Design (CAD) and Computer Aided Engineering (CAE) software. Subsequently a
prototype is built to validate the functionality of the new track system which is more efficient in
absorbing the vibration and shock. Analysis and optimisation of the prototype is performed using
CAD method with the CATIA V5 R16 software.
Introduction
According to the statistics on death rate of fire fighters reported in the USA during the early
1980s, 1.9 fire fighters were reported to be killed per year for every 100,000 structure fires [1]. This
rate however increased to 3.0 fatalities for every 100,000 structure fires during the 1990s [2]. The
reported causes for Line of Duty Deaths (LODD) include smoke inhalation, crushing injuries and
burns [3]. This scenario triggered the need to develop fire fighting technologies where companies in
the USA and Japan have been extensively involved in the research and development of fire fighting
technology. Many studies [4-8] were made on replacing fire fighters with machines in dangerous
situations to reduce the fatalities of fire fighters. The fire fighting machines can assist the fire
fighters in extinguishing fire in the dangerous areas without the fire fighters themselves needed to
be present at the area.
Current UTeM’s Fire Fighting Machine. Current UTeM’s fire fighting machine (Fig. 1) was
built in 2007 by the Faculty of Mechanical Engineering (FKM) with the collaboration of a local
engineering company. The main goal of the machine is to extinguish fire in situations that will cause
harm to human lives.
It is composed of metal body, electrical and electronic board, hydraulic components and
mechanical components. The machine is run by two electric direct current motor made by Sanpo
Electric Co. Ltd. with six rechargeable batteries. The fire fighting machine is controlled by using
radio frequency control where the operator can operate the machine in a safe distance from fire. The
track system of the machine is consists of a heavy duty belt, one drive sprocket, one idler sprocket
and five bogies (Fig. 2). However, the current track system shown in Fig. 2 does not have
suspension system to absorb vibration and shock. Therefore, when the fire fighting is moving on
rough terrains sharp jolts will be created causing the track to lift from the ground and eventually
makes manoeuvring difficult. Besides, the vibration and shock will also cause damage to the track
system.
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP,
www.ttp.net. (ID: 219.93.10.33, Universiti Teknikal Malaysia Melaka (UTeM), Durian Tunggal, Malaysia-04/03/13,10:13:12)
Applied Mechanics and Materials Vol. 315
237
Figure 1. Current UTeM's fire fighting machine
Figure 2. Track system of UTeM's fire fighting machine
Methodology
Firstly, CATIA V5 R16 is be used to create the actual drawing with actual dimensions which
include part designs, assembly drawings and exploded drawings. Subsequently, the bill of materials
(BOM) is generated for cost estimation purposes. A prototype of the track system is built by using
aluminium for the body, small wheel and conveyor belt for the track system.
After obtaining the design, Finite Element Analysis (FEA) software is used to perform analysis
on the design. Some assumptions were made to choose the material and allowable weight to set the
boundaries for analysis purposes. Results from the analysis are able to measure the force that can be
exerted on the track system.
Lastly, the new track system is being optimised by the means of FEA software by analysing the
critical part of the track system. A numerical analysis simulation is performed on the design to
compute Von Mises stress and the sensitivity of the performance measures with respect to the
238
Mechanical & Manufacturing Engineering
design parameters. Then an optimisation algorithm is used to compute new design parameters until
an optimum design is achieved.
Selected Conceptual Design. The selected conceptual design shown in Fig. 3 is using roller
chain as its track because roller chain has no slippage or creep. Thus, there will not be issue of
power lost due to slippage. Moreover, roller chain can drive a number of shafts from a single source
of power and the failure rate of roller chain is also very low due to low tensile strength. Chain drives
are more practical to operate at low speed as well as high temperature. The ability of chain drives to
withstand deterioration caused by oil, grease, sunlight, chemical and abrasive conditions is also an
important factor to choose it as the track. Roller chains can also operate in wet conditions with
lesser problems as compared to belts. On the other hand, the rigid frame type I is used for the
chassis because it is more suitable to withstand high moment, stress and force. Besides, it is not
easily damaged due to vibration and shock because of its rigidity. The shock absorber will be fitted
with motorcycle shock absorbers.
Figure 3. Selected conceptual design
Simulation and Analysis Results
Catia V5R16 is used to do simulation and analysis on the shaft of the roller in order to compare
the current fire fighting machine with new conceptual design. This is because the new conceptual
design does not based on the current one but it is a whole new concept. The current track system
will be compared to the new track system in the terms of Von Mises stress.
According to Von Mises Stress (Distortion Energy Theory), it proposes that the total strain
energy can be separated into two components: the volumetric (hydrostatic) strain energy and the
shape (distortion or shear) strain energy. It is proposed that yield occurs when the distortion
component exceeds that at the yield point for a simple tensile test. The yield started at the edge of
the current track system’s roller which is shown in the Fig. 4 when a large force exerted on it. This
is because most of the stress caused by the body weight is exerted on the roller. Compare to the new
conceptual design in the Fig. 5, the yield is started at the shaft only. However, the roller and its
holder remain on its state. The yield is more on the shaft because it is distorted by the tensile force
from the suspension system and the roller holder.
Applied Mechanics and Materials Vol. 315
239
Figure 4. Von Mises Stress analysis of current fire fighting machine
Figure 5. Von Mises Stress analysis of new conceptual design
Discussions and Conclusion
The weight has an importance role to improve the track system as it will exert a high force and
stress on the track system. A greater effort is needed to move the track system due the weight of the
machine body. In order to produce greater effort, a higher power motor is needed and this will
increase electricity consumption. Hence, if the body weight of the fire fighting machine is too
heavy, it reduce the efficiency of the track system. The body weight of the fire fighting machine can
be modified so it will become lighter by using lighter material to build the body of the fire fighting
machine. Meanwhile, the strength of the new material should not be neglected. Besides, the
structure design of the fire fighting machine also needs improvement in order to reduce the weight.
One of the factors that contribute to the heaviness of the current UTeM fire fighting machine is the
existence of hydraulic nozzle as there are some solid structures. This can be improved by using
lighter structures such as hollow beam and hollow cylinder to substitute the solid parts
240
Mechanical & Manufacturing Engineering
In conclusion, the state of art of the track system for the existing fire fighting machine has been
studied. An improved track system has been designed and developed followed by up-scaling and
optimising the new track system CATIA V5R16. From the result, it is shown that the new design of
fire fighting machine track system has improvement compared to the current UTeM fire fighting
machine. The problem of shock and vibration absorption that the when moving on a rocky surface
has been solved by using absorber in the track system.
Acknowledgement
This project is funded by Universiti Teknikal Malaysia Melaka (UTeM) under the Short Term
Research Grant. Special thanks to Faculty of Mechanical Engineering for the support.
References
[1] International Association of Fire Fighters (IAFF), 2000, “Death and Injury Survey,
Washington,” Available from: http://www.iaff.org/ HS/PDF/ 2000%20D&I.pdf. Accessed on
5th September 2008.
[2] S.N. Kyle, 2007, “NFPA Releases Firefighter Death Study, U.S.A,” Available from:
http://cms.firehouse.com/content/section/news. Accessed on 5th September 2008.
[3] N. Rosmuller and B.J.M., Ale, “Classification of fatal firefighter accidents in the Netherlands:
Time pressure and aim of the suppression activity,” Journal of Safety Science, 2008, 46, page
282 –290.
[4] Shanghai Qiangshi Fire-fighting Equipment Co. Ltd., 2007, “Qiangshi Fire Fighting Robot,
China,” Available from: www.qs119.com/en/ showpro.asp?id=530. Accessed on 5th September
2008.
[5] E. Sofge, 2007, “First Firefighting Robots Deployed, Could Spark Autonomous Dept. Las
Vegas,” Available from: http://www.popularmechanics.com/science/roboticsl. Accessed on 5th
September 2008.
[6] A. Konda, “The Fire Fighting Snake Robot. Europe,” Available from: http://www.sintef.com.
Accessed on 4th September 2008.
[7] HKFSD, “Mobile Fire Fighting Supporting Machine LUF 60R. China,” Available from:
http://www.hkfsd.gov.hk/home/images/ equipment/fire/e_luf60.html. Accessed on 13th
September 2008.
[8] NEVA, “Mobile Fire Fighting Robot. Russia,” Available from: http://www.neva.ru/CNIIRTC/Firemen/html. Accessed on 13th September 2008.
© (2013) Trans Tech Publications, Switzerland
doi:10.4028/www.scientific.net/AMM.315.236
Up-Scaling and Optimisation of Fire Fighting Ground Vehicle Track
System
CheeFai Tan1, a, Ranjit Singh Sarban Singh2, V.K. Kher1 and H.F. Kong1
1
Integrated Design Research Group (IDEA),Faculty of Mechanical Engineering,
Universiti Teknikal Malaysia Melaka (UTeM), Melaka, Malaysia
2
Faculty of Electronic and Computer Engineering, Universiti Teknikal Malaysia Melaka (UTeM),
Melaka, Malaysia
a
cheefai@utem.edu.my
Keywords: Fire fighting machine; Track system; Absorber; Up-scaling and optimisation
Abstract. Current UTeM’s fire fighting machine is developed to operate indoor only. It is not
efficient when it is operating on rocky surfaces (outdoor) as it faces the problem of shock and
vibration reduction. The track system of the machine cannot move smoothly because the rollers are
fixed to the chassis. This paper describes the method of up-scaling and optimising the track system
for the current fire fighting machine. The new track system concept is firstly developed by using
Computer-Aided Design (CAD) and Computer Aided Engineering (CAE) software. Subsequently a
prototype is built to validate the functionality of the new track system which is more efficient in
absorbing the vibration and shock. Analysis and optimisation of the prototype is performed using
CAD method with the CATIA V5 R16 software.
Introduction
According to the statistics on death rate of fire fighters reported in the USA during the early
1980s, 1.9 fire fighters were reported to be killed per year for every 100,000 structure fires [1]. This
rate however increased to 3.0 fatalities for every 100,000 structure fires during the 1990s [2]. The
reported causes for Line of Duty Deaths (LODD) include smoke inhalation, crushing injuries and
burns [3]. This scenario triggered the need to develop fire fighting technologies where companies in
the USA and Japan have been extensively involved in the research and development of fire fighting
technology. Many studies [4-8] were made on replacing fire fighters with machines in dangerous
situations to reduce the fatalities of fire fighters. The fire fighting machines can assist the fire
fighters in extinguishing fire in the dangerous areas without the fire fighters themselves needed to
be present at the area.
Current UTeM’s Fire Fighting Machine. Current UTeM’s fire fighting machine (Fig. 1) was
built in 2007 by the Faculty of Mechanical Engineering (FKM) with the collaboration of a local
engineering company. The main goal of the machine is to extinguish fire in situations that will cause
harm to human lives.
It is composed of metal body, electrical and electronic board, hydraulic components and
mechanical components. The machine is run by two electric direct current motor made by Sanpo
Electric Co. Ltd. with six rechargeable batteries. The fire fighting machine is controlled by using
radio frequency control where the operator can operate the machine in a safe distance from fire. The
track system of the machine is consists of a heavy duty belt, one drive sprocket, one idler sprocket
and five bogies (Fig. 2). However, the current track system shown in Fig. 2 does not have
suspension system to absorb vibration and shock. Therefore, when the fire fighting is moving on
rough terrains sharp jolts will be created causing the track to lift from the ground and eventually
makes manoeuvring difficult. Besides, the vibration and shock will also cause damage to the track
system.
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP,
www.ttp.net. (ID: 219.93.10.33, Universiti Teknikal Malaysia Melaka (UTeM), Durian Tunggal, Malaysia-04/03/13,10:13:12)
Applied Mechanics and Materials Vol. 315
237
Figure 1. Current UTeM's fire fighting machine
Figure 2. Track system of UTeM's fire fighting machine
Methodology
Firstly, CATIA V5 R16 is be used to create the actual drawing with actual dimensions which
include part designs, assembly drawings and exploded drawings. Subsequently, the bill of materials
(BOM) is generated for cost estimation purposes. A prototype of the track system is built by using
aluminium for the body, small wheel and conveyor belt for the track system.
After obtaining the design, Finite Element Analysis (FEA) software is used to perform analysis
on the design. Some assumptions were made to choose the material and allowable weight to set the
boundaries for analysis purposes. Results from the analysis are able to measure the force that can be
exerted on the track system.
Lastly, the new track system is being optimised by the means of FEA software by analysing the
critical part of the track system. A numerical analysis simulation is performed on the design to
compute Von Mises stress and the sensitivity of the performance measures with respect to the
238
Mechanical & Manufacturing Engineering
design parameters. Then an optimisation algorithm is used to compute new design parameters until
an optimum design is achieved.
Selected Conceptual Design. The selected conceptual design shown in Fig. 3 is using roller
chain as its track because roller chain has no slippage or creep. Thus, there will not be issue of
power lost due to slippage. Moreover, roller chain can drive a number of shafts from a single source
of power and the failure rate of roller chain is also very low due to low tensile strength. Chain drives
are more practical to operate at low speed as well as high temperature. The ability of chain drives to
withstand deterioration caused by oil, grease, sunlight, chemical and abrasive conditions is also an
important factor to choose it as the track. Roller chains can also operate in wet conditions with
lesser problems as compared to belts. On the other hand, the rigid frame type I is used for the
chassis because it is more suitable to withstand high moment, stress and force. Besides, it is not
easily damaged due to vibration and shock because of its rigidity. The shock absorber will be fitted
with motorcycle shock absorbers.
Figure 3. Selected conceptual design
Simulation and Analysis Results
Catia V5R16 is used to do simulation and analysis on the shaft of the roller in order to compare
the current fire fighting machine with new conceptual design. This is because the new conceptual
design does not based on the current one but it is a whole new concept. The current track system
will be compared to the new track system in the terms of Von Mises stress.
According to Von Mises Stress (Distortion Energy Theory), it proposes that the total strain
energy can be separated into two components: the volumetric (hydrostatic) strain energy and the
shape (distortion or shear) strain energy. It is proposed that yield occurs when the distortion
component exceeds that at the yield point for a simple tensile test. The yield started at the edge of
the current track system’s roller which is shown in the Fig. 4 when a large force exerted on it. This
is because most of the stress caused by the body weight is exerted on the roller. Compare to the new
conceptual design in the Fig. 5, the yield is started at the shaft only. However, the roller and its
holder remain on its state. The yield is more on the shaft because it is distorted by the tensile force
from the suspension system and the roller holder.
Applied Mechanics and Materials Vol. 315
239
Figure 4. Von Mises Stress analysis of current fire fighting machine
Figure 5. Von Mises Stress analysis of new conceptual design
Discussions and Conclusion
The weight has an importance role to improve the track system as it will exert a high force and
stress on the track system. A greater effort is needed to move the track system due the weight of the
machine body. In order to produce greater effort, a higher power motor is needed and this will
increase electricity consumption. Hence, if the body weight of the fire fighting machine is too
heavy, it reduce the efficiency of the track system. The body weight of the fire fighting machine can
be modified so it will become lighter by using lighter material to build the body of the fire fighting
machine. Meanwhile, the strength of the new material should not be neglected. Besides, the
structure design of the fire fighting machine also needs improvement in order to reduce the weight.
One of the factors that contribute to the heaviness of the current UTeM fire fighting machine is the
existence of hydraulic nozzle as there are some solid structures. This can be improved by using
lighter structures such as hollow beam and hollow cylinder to substitute the solid parts
240
Mechanical & Manufacturing Engineering
In conclusion, the state of art of the track system for the existing fire fighting machine has been
studied. An improved track system has been designed and developed followed by up-scaling and
optimising the new track system CATIA V5R16. From the result, it is shown that the new design of
fire fighting machine track system has improvement compared to the current UTeM fire fighting
machine. The problem of shock and vibration absorption that the when moving on a rocky surface
has been solved by using absorber in the track system.
Acknowledgement
This project is funded by Universiti Teknikal Malaysia Melaka (UTeM) under the Short Term
Research Grant. Special thanks to Faculty of Mechanical Engineering for the support.
References
[1] International Association of Fire Fighters (IAFF), 2000, “Death and Injury Survey,
Washington,” Available from: http://www.iaff.org/ HS/PDF/ 2000%20D&I.pdf. Accessed on
5th September 2008.
[2] S.N. Kyle, 2007, “NFPA Releases Firefighter Death Study, U.S.A,” Available from:
http://cms.firehouse.com/content/section/news. Accessed on 5th September 2008.
[3] N. Rosmuller and B.J.M., Ale, “Classification of fatal firefighter accidents in the Netherlands:
Time pressure and aim of the suppression activity,” Journal of Safety Science, 2008, 46, page
282 –290.
[4] Shanghai Qiangshi Fire-fighting Equipment Co. Ltd., 2007, “Qiangshi Fire Fighting Robot,
China,” Available from: www.qs119.com/en/ showpro.asp?id=530. Accessed on 5th September
2008.
[5] E. Sofge, 2007, “First Firefighting Robots Deployed, Could Spark Autonomous Dept. Las
Vegas,” Available from: http://www.popularmechanics.com/science/roboticsl. Accessed on 5th
September 2008.
[6] A. Konda, “The Fire Fighting Snake Robot. Europe,” Available from: http://www.sintef.com.
Accessed on 4th September 2008.
[7] HKFSD, “Mobile Fire Fighting Supporting Machine LUF 60R. China,” Available from:
http://www.hkfsd.gov.hk/home/images/ equipment/fire/e_luf60.html. Accessed on 13th
September 2008.
[8] NEVA, “Mobile Fire Fighting Robot. Russia,” Available from: http://www.neva.ru/CNIIRTC/Firemen/html. Accessed on 13th September 2008.