Larry Jordan II Buffalo NY 5 stems inc 5 stems llc
                     MAE 494: Senior Design Project Report
The Ascension Project
Group # 27
Nicholas Altanian, Jason D’Souza, Andrew Lewis, Joshua Matter, Alec Brewer
May 8, 2015
LIST OF TABLES
Table 1. List of customer requirements………………………………………………………...
………………….3  Table 2. Technical 
specifications………………………………………………………………………….........….4  Table 3. 
Decision matrix……………………………………………………………………………………….……8
Table 4. Tower stress analysis 
results…………………………………………………………………………...14  Table 5. Pulley housing 
floor stress analysis results………………………………………………………..….16  Table 6. Total 
cost breakdown………………………………………………………………………..…………..17  Table 7. 
Tower income………………………………………………………………………………………….....17  Table 
8. Estimated savings………………………………………………………………………………………..18
iii
EXECUTIVE SUMMARY
This report consists of detailed design information pertaining to the design of a monopole,  
telecommunications tower, intended to eliminate the need for climbing in order to 
maintenance  communication equipment located on the tower. The tower design is based 
on a conventional elevator,  pulley/counterweight, lift system that lowers six individual 
antenna platforms to ground level for  maintenance. The design process, embodiment 
design, design feasibility analyses and  manufacturing/assembly considerations are 
discussed in detail.
iv
1 INTRODUCTION
This section consists of a description of our senior design project’s motivating problem. 
Project goals,  deliverables and metrics of project success are also clearly defined. An 
overview of the contents of this  report is provided in section 1.4.
1. Problem Overview
Our senior design project is focused on the development of a design for a new cell phone 
tower aimed to  eliminate the issues currently associated with cell phone towers. The primary 
issue we are concerned with  is the dangerous task of maintaining the equipment on these 
towers. Tower workers need to climb  towers ranging anywhere from a few hundred to over 
two thousand feet in height. With eighteen deaths  in 2019 alone1, tower climbing is 
considered to be one of the most dangerous jobs in America1.
Our project sponsor, Larry Jordan (CEO of SAT Corp), proposed his idea for a tower that would 
make  tower maintenance entirely risk free. Instead of having workers climb a tower, Mr. 
Jordan wants us  to design a tower that will bring the equipment down to ground level. 
The tower will need to be  capable of allowing maintenance of one carrier without 
interference of service to any of the other carriers  on the tower.
2. Expected Project Deliverables
Due to the size and complexity of this project, it is important that we define reasonable 
expectations for  final project deliverables. By the end of the project period, we plan to have 
a fully detailed design that  addresses a majority of the customer requirements. This design 
will take shape through 3D CAD  software (Creo Parametric). In order to better convey the 
function of our design, we plan to animate the  3D model through Creo. The goal is to 
provide enough detail and information, such that a prototype  of our design can 
eventually be built for future testing.
3o.f oMuer tfirincasl o df ePsriogjne.c tT Shuecscee smsetrics  How well customer requirements (defined in Section 2.1) 
include: are met  Estimated payback periodWe have decided upon several performanceFa mctoerstr oicf ssa tfehtayt o wf cirlilt iacalllo cwom upso nteon tps rboapseedr loyn e fivnaitleu ate 
the success element and
Our overall measurement of success wilfla tbigeu e hlifoew a nawlyeslels our design meets the customer 
requirements defined  in our House of Quality. We will perform combinations of qualitative 
and quantitative assessments to gauge  how well each customer requirement was met. The 
highest weighted requirements are focused on the cost  and reliability/integrity of our design. 
The cost of our design will be compared to the cost of a 200 ft.  monopole tower (estimated 
at $80,000) 1. Assessment of overall system reliability/integrity will require Finite  Element 
Analyses (FEA) on major components of our design. Major components of our design will 
consist  of the tower’s structural elements. We will use Creo Simulate to perform our FEA. 
The goal of our FEA  will be to simulate stress responses of major components placed under 
worst case loading scenarios  (includes responses to wind forces) and compute corresponding 
factors of safety.
1.4 Report Overview
This report consists of a detailed breakdown of the problem at hand, concept 
generation/selection process,  and embodiment design details. The layout of the report 
follows the structured design process we
have been following since we began the project in the Fall semester. Descriptions of each 
major stage  in the process, along with their respective outputs, are provided for each 
section.
1
1 http://www.wirelessestimator.com/
2 PROBLEM CLARIFICATION
This section consists of the customer requirements defined for the design of our 
tower and their
corresponding technical specifications. The requirements break down the overall design 
problem and  represent the main driving factors that will dictate the design of our tower. The 
technical specifications  represent quantified design performance targets.
1. Customer Requirements
A majority of the customer requirements, listed in Table 1, were developed after our kickoff 
meeting with  our project sponsor, Larry Jordan. These requirements consist of both 
innovative and standard features
that Mr. Jordan expects to see in our tower design. After receiving our review on our Mini 
Project 2 Reports,  redundant and unnecessary requirements were removed. Requirements 
more specific to our proposed  design were appended after receiving Mr. Jordan’s review on 
our embodiment design of “The Octotower”.  The customer requirements were weighted 
according to importance and incorporated into our House of  Quality to analyze relationships 
be#tween rCeuqsutoirmemere Rnetsq uainredm tencthnical specifications (See ApDpesncdriixp tAio).n
1 Safe to service The tower should make maintenance absolutely risk free.
Antennae can beT able 1. List of customer requirements
2 remotely  pointed in Individ al antenna direction should be capable of fine 
the azimuth  necessary remote  adjusts.
The structure must conform to the painting and lighting
3 Meets FAA visibility standards specifications set forth in the FAA’s final 
determination of “no  hazard” and the associated FAA 
study for that particular  structure.
4 Non-disruptive to The tower should not be disruptive (too noisy, 
surrounding  dangerous, etc.)  to surrounding residents 
inhabitants and/or wildlife.
5 Capable of supporting at This is a requirement for design set by the project 
least  five carriers sponsor,
SAT Corp.
The tower should be sufficiently grounded, such that all
6 Must withstand lightning equipment on the tower is protected in the event of a 
strikes lighting  strike.
Every component of the tower must be able to 
7 Must withstand forces withstand the  strong wind forces expected at tall 
due to  strong heights. Failure of any  tower component is a 
winds potential safety hazard.
8 Fast maintenance speed The time it takes for technicians to reach the 
communication  equipment on the tower should be 
as short as possible.
9 Environmentally friendly The tower should not negatively impact the 
environment on  both local and global 
scales.
The tower should be designed in such a way that
10 Safe to construct construction/assembly of the tower will involve little 
to no life  safety risk.
11 Easy to transport components Individual components of the tower should be easily 
capable  of shipping via ground, air, and 
water.
12 Low Capital Cost The overall cost of the tower should be low enough 
to justify  use over a conventional 
tower.
13 Sleek Design The overall diameter of the tower should be as 
small as  possible. The tower should also be 
aesthetically pleasing. 2
The tower should allow a technician to service one of the
14 Equipment maintenance carriers on the tower without having to take any 
should  be isolated other carrier  out of service.
15 Ample advertising space The tower should have space for advertisement to be 
clearly  displayed.
16 Easy to climb in the In the event of a mechanical failure, there 
event of  should be a  relatively safe/easy way for workers 
mechanical failure to scale the tower.
The design of the tower should accommodate the use of
17 Complies with OSHA personal protection equipment (PPE) as specified in 
Safety  OSHA  safety standards.
Standards
18 High Reliability Consistent proper function of the tower is crucial in 
order to  ensure that any need for tower climbing is 
kept to a minimum.
The tower should be capable of delivering the power 
19 Deliver power to cables
carrier’s  needed by carrier communication equipment at 
Equipment any height  along the tower.
Capable of accommodating all
2.20 Technical Speciufircraetniot ns The tower should be able to properly hold all 
Technical speccoimmunication  
types of  communication that are commonly 
fications were establishedu sbeyd t rina ntshlea tiinndgu tshtrey .customer requirements, defined in 
Section 2.1,equipment on the 
into quantifiable mdaerskigent  performance targets. Each technical specification corresponds to a 
customer  requirement and can be measured according to some type of unit. The importance 
of each technical  specification was derived through by establishing the strength of 
relationships with the weighted customer  requirements in our House of Quality (See 
Appendix A for HOQ). The relative weights/importance from the  HOQ, as shown in Table 2, 
indicate that overall cost and the structural factor of safety are the most  important technical 
specifications that will need to be addressed in our design.
Relative  
# Technical  Units Table W2.e Tigehcth/ n ical spTeacrigfiectations Description
Specification Importance
This is a ratio of the 
Structur
1 maximum  stress that key al  FOS 12.7 1.5 components of our  design 
Factor can withstand to the  
of  maximum stress experienced.
Safety
Degrees of
2 Freedom Degrees 1.5 Max This the amount of rotation 
for  the  each antenna is 
Antenna capable of.
Maximum  The distance the tower can be 
3 Distance  seen is an important f t . 2.9 Max
Tower  is consideration  not only for the 
Visible From avian wildlife but  as well as for low flying aircraft.
The decibels that are emitted 
Noise 
4 2.3 Min from  lifting the antennas Level  dB should not  disturb people 
During  that live in the  vicinity.
Operation
The tower should be designed 
Maximu to  support the weight of all 
5 m  lbf. 8.5 Max the  communication 
Weight  equipment that will  be placed 
Supporte on the tower along with  the 
d weight of the tower itself.
Maximum amount of voltage 
Maximum  the  tower is able to withstand 
6 Voltage Able V 2.0 Max (all  components and 
to  Withstand equipment on the  tower still 3
properly functioning)  from a 
lightning strike
Maximum Wind Maximum force, due to wind, 
7 Load lbf. 5.3 Max that
Before  the tower can withstand 
Failure without  any 
failure.
The speed at which the 
Speed of  platform  containing all the 8 ft/s 3.9 Max
Platform communication
Lift raises and lowers will need 
to be  fast enough for quick 
service
projects.
This is a measure of the 
total  estimated 
9 Carbon lbm. of  1.6 Min greenhouse gas  emission 
 CO2 associated with the
Footpri manufacturing processes 
nt and  function of our tower 
design.
Maximum  
Height This is the maximum height 
10 Required to ft . 1.8 Min that a  worker would be 
 Climb required to work  at during 
During construction of the tower.
Construction
Dimensions This describes the size of the
11 of  Largest  ft. x ft. x ft. 2.5 Min largest (disassembled) 
Component component  of the tower. Important for  transportation 
requirements.
12 Overall Cost $ 12.4 Min This includes the cost of material,  manufacturing, 
and installation.
The overall diameter of the 
13 Overall 5.8 Min tower  includes the tower f t .
Tower  base plus the  span of any 
Diameter extending structural  
members.
This is the average time that 
14 Average Minutes 6.3 Min a  carrier’s communication  
Time  Out of equipment is out of service 
Service when  NOT being 
maintenanced.
Available  This is the amount of space  
15 Advertisin ft .2 4.8 Max available to use for clearly 
g  Space visible  advertisements.
Climbin This is the amount of space  
16 g  2 5.6 Max available to incorporate a  ft .
Space  ladder/pegs/etc. for climbing 
Availabl in the  event of lift system 
e failure.
Factor of  This is the factor of safety of 
17 Safety of any  fall protection system Fall  FOS 6.5 5 to be  integrated into the 
Protection  design of the  tower.
System
This is the expected life span 
18 Fatigue Life 5.2 Max of  major moving components Years 4
of  Moving of our  design under worst 
Parts case scenario  conditions.
This is the amount of power 
Power  
19 2.1 200 W our  tower is required to Delivered W per  deliver to any  communication 
to  channel equipment located  at any 
Antennas height.
Available  
Space for  Total space available to hold 20 2Communicati ft . 6.2 Max the  communication 
on  equipment for all  carriers on 
Equipment the tower.
3 CONCEPT DESIGN
This section discusses the process we followed to arrive at a design concept that promised 
to satisfy a
majority of the customer requirements defined in Section 2.1. Our process comprised of two 
different  stages. During our divergent design stage (discussed in Section 3.1), we used two 
different idea generation  methods to pool together as many distinct design ideas as we can. 
We turned to convergent processes  (discussed in Section 3.2), to filter our pool of design 
ideas and finally arrive at a design concept to further  pursue.
1. Concept Generation
Our group’s concept generation process consisted of one group generation method and one 
individual  generation method. Our first batch of ideas were generated using the 6-3-5 
technique. While we were able  to generate many ideas through this method, we quickly 
realized that there wasn’t a lot of variation amongst
the pool of ideas.
We then decided to try an individual idea generation method in hopes of developing a larger 
variety of  design concepts. We used a forced connection approach through photographs. 
Each group member  posted five photos taken from the internet onto the group’s google 
drive. We gave each other a few days  to develop concepts inspired by these photos and the 
result was a larger pool of ideas with greater variety.  Each group member communicated 
their ideas by sketching and writing short descriptions. In total, we  developed a pool of 
seventeen distinct design ideas. A few examples of the photos we used are shown in  Figure 
1.
Figure 1. Concept generation photos
5
3.2 Concept Selection
In order to determine the best overall concept out of our pool of ideas, we rated each idea (on 
a scale of 1-
100) in accordance to six of the most important technical specifications. We organized this 
information  into the decision matrix, shown in Table 3, to arrive at the concept we would 
further pursue.
Table 3. Decision matrix
The weighting system used in the decision matrix is designed to apply relative emphasis on 
the design  attributes that are most important to the desired outcome. The weights chosen 
reflect the importance of the  specific design attribute.
After assigning weights to each design, each design was scored 0-100 based on its conformity 
towards that  attribute. The Octotower received the highest overall score of 89. This score 
reflects the overall best  coverage of each attribute. The three runner ups are the Bloom 
“Stacking” System, with a score of 71.2.  The Overlapping Platform system, with a score of 
70.7, and the Exterior Lifting System, with a score of
69.4. The Octotower design beat these designs by a significant amount. However, the runner-
up designs  still have potential with some redesign. These redesigns provide alternatives and 
also possible design ideas
that can be used to optimize the Octotower design.
6
4.1.1 Tower Structure
The tower structure is designed to a height of 
190 ft.
and has a tapered profile (0.574 degree). The 
taper  provides a robust structural design 
along with sleek  aesthetics. The tower’s 
structural design consists of  eight separate 
sections. Each section has a  hexagonal cross 
Ssecttiion s( S2e e–  7Fi ghuarvee 4 I)-.beams bolted on at each 
face  of the tower. These I-beams serve as 
guiderails for  the antenna platforms to ride 
along via guide shoes.  There is one antenna 
platform that rides along each  face of the 
tower (six platforms total). The bottom  
section houses the drive motors and has a 
door for  easy accessibility when maintenance Figure 4. Tower cross-section
is needed. The  top section of the tower 
houses the pulleys. Each  section is bolted 
together via external flanges. Manufacturing considerations were key 
driving  factors of the tower’s structural 
design. Bolted  connections were chosen 
because we wanted to  keep the need for 
welding down to a minimum and  wanted a 
design that would be able to use common  
machinery currently used to make 
Tmraonsoporlteast.ion and assembly considerations 
were  also crucial to the tower’s structural 
design. The  tower was designed such that 
the largest  component of the tower is 
capable of transportation  via trucks, freight 
boats, and cargo planes.  External flanges 
were chosen for joints because  they provide 
Figure 5. Section 4 model a strong structural connection and  easy 
assembly.
In order to ensure safe structural stability of the tower structure, stress analyses were 
conducted at three  major areas of concern (see Section 4.2).
Figure 6. Drive housing Figure 7. Flange joint
8
4.1.2 Antenna Platform and Guide Shoe  
Each antenna platform is designed to 
hold  ten standard sized (8 ft. x 1 ft. x 
½ ft.)  antennas and has roughly 36 
square feet  of floor space for 
additional carrier  equipment. The 
front face of the platform  provides 
120 square feet of area per  platform 
for advertising space (see Figure  8).
The framing of the platform consists 
of 2  in. round tubes connected to 
grate flooring.  These tubes are 
connected, via U-bolts, to  1 ¼ in. 
tubes that the antennas mount onto  Figure 8. Full platform model
via mounting brackets.
Each platform has two custom designed guide shoes that ride along the I-beams bolted along 
each face of  the tower. The guide shoes keep the platform in place such that it is only 
capable of moving vertically.  Each shoe consists of eight purchased wheels with load ratings 
well above the estimated platform weight.  Incorporated into the guide shoes are two eyebolts 
that connect to the steel cables used to lift/support the  platform. The guide shoes are 
connected to the antenna platform via steel I-beams and bolted connection.
Figure 9. Guide shoe assembly/section view
Design for environment concerns were taken into account when designing the antenna 
platform. A common  problem with communication towers is that they often serve as nesting 
spots for birds. Often times, if there  is a nest on a tower, tower workers are either prohibited 
from working on the tower and/or have to contact  local wildlife agencies for further 
instruction on how to handle the situation. This can severely impede  necessary tower 
maintenance. A simple, cheap and effective solution to this issue would be to place netting  
along the back side of the platform and bird spikes on the top of the platform in order to avoid 
nesting.
9
4.1.3 Drive/Lift System
The drive/lift system is similar to that 
of the
conventional elevator. Six gearless traction 
motors,  located at the base of the tower, 
release and retract  steel cables, connected to 
the counterweight, in order  to lower and raise 
the platform, respectively. There is  one motor 
for each platform/counterweight, thus  allowing 
for each platform to be raised/lowered  
independently from one another. Maintenance 
for one  carrier does not interfere with the 
service of the other  carriers located on the 
tower. In order to significantly  reduce costs, an Figure 10. XINDA WWTY
existing gearless motor that meets  necessary gearless traction motor
specifications was chosen. These gearless  
motors can be operated remotely via a control The counterweight is designed to be 
box  located outside of the tower. roughly 75%  of the load placed on the 
antenna. The weight of  the counterweight 
can be easily adjusted to  account for 
varying loads placed on the platform.  With 
the counterweight counteracting the load 
of  the platform, the motors at the base of 
the platform  are only responsible for 
providing enough power  to lift the 
difference in weight between the platform  
and counterweight, thus significantly 
reducing the  required motor size. Tension is 
kept in the cables  between the motor and 
counterweight in order to  keep the 
Figure 11. Hollister Whitney  counterweight in place as it travels along  
counterweight frame the tower. Counterweight frame and 
weights that  meet the weight and 
Two pulleys per platform, located at the top of the gtoewomere (tsriecea lF igdueres ig1n2 ), c harenqguei rtehme ents are 
direction of the steel  cables that attach the antenrneaa pdlialyt foramva tiola tbhle cofuonr terpwuercighhats.e B ot h ftrhoem  
pulleys and steel cables are  purchased componenntsu mthearto muse elte tvhaet olor asdu prepqlyu ciroempeanntsie ws.ith a 
factor of safety of 3.
Figure 12. Pulley housing configuration and model
10
4.1.4 Brake/Fail-safe
The primary brake is integrated into each of the six gearless traction motors. This brake will 
hold the  antenna platform in place during regular operation.
In the unlikely event that the cables snap/fail, elevator buffers, designed to bring free falling 
elevators to a  safe stop, are located at the bottom of the tower. These buffers are bolted into 
the ground directly  underneath each antenna platform. Purchased hydraulic buffers, that 
meet impact load/speed  requirements, were chosen for our design. The buffers require little 
to no maintenance and can be easily  replaced if needed.
Figure 13. Oleo SEB 18 Hydraulic Buffer
2. Detailed Design Analysis
Due to the fact that a majority of the tower’s design is comprised of purchased 
components with known
load ratings, design analyses was only performed on several components of major concern. 
These  components include the overall tower structure, the I-beam guiderails, and the top 
section (pulley housing)  of the tower.
1. Tower Stress Analysis
Finite Element Analysis (FEA) was used to determine the wall thickness of the tower that 
would achieve a  target factor of safety of 1.5. The design was tested under worst-case-
scenario loading conditions.
 Known:
Material properties of the tower structure (ASTM A572 – 65), tower geometry, air 
properties at STP,  and platform/counterweight loads are known.
 Assumptions:
The following assumptions were made to simplify analysis of the tower model while 
still maintaining  validity of results:
1. 110 mph wind
2. Angle of attack is at 0 degrees
3. Joints at the flange are rigid connections
4. Base of tower is rigidly constrained
5. Weight from antenna platforms and counterweights act vertically downward 
from the top of  the tower
6. Tower drag coefficient is 0.95 11
 Free Body Diagram and Relevant Equations:  
Figure 14 represents a simple free body 
diagram  showing the location of the wind 
and  platform/counterweight loads on the 
tower. Eq.
(1) was used to determine the force from the  
wind acting on the tower.
Wind Force (FD):
F =  1 2D ρv CdA Eq. (1)2
ρ  =  air density 
 v =  wind speed
Cd =  drag 
coefficient
A =  effective area
Figure 14. Tower free body diagram
 Results:
After simulating the stress in the tower with five different wall thicknesses, the optimal 
wall thickness
was found to be 3/8”. This thickness resulted in a maximum stress of roughly 41,000 
psi and a  corresponding factor of safety of roughly 1.56. Table 4 shows the simulation 
results and  corresponding factors of safety.
Wall Thickness (in.) Max Stress (psi) Factor of Safety
1/8 98,333 0.66
1/4 62,152 1.05
3/8 41,605 1.56
7/16 34,893 1.86
1/2 26,475 2.45
Table 4. Tower stress analysis results
Note: Von-Mises, displacement and convergence diagrams can be found in 
Appendix F
12
2. I-Beam Stress Analysis
The I-beam Guide Rail is the component in which the antenna travels on. The operation of the 
tower strongly  depends on the reliability of this component, so it is necessary to perform a 
stress analysis that will confirm
the reliability. The antenna is supported in the vertical direction by a cable that is connected 
to the top guide  show. At any given position, the mass of the antenna creates a moment 
about the top guide shoe, which is  resolved into normal forces applied to the outer face of 
the I-beam at each of the lower guide shoes.  Additionally, any wind exerts a force on the 
antenna, which results in a moment on I-beam at each guide  shoe.
 Known:
The platform geometry, I-beam material (ASTM A36), I-beam size (W14x90), and air 
properties at  STP are known.
 Assumptions:
1. 110 mph wind load
2. Angle of attack is 0 degrees
3. I-beam is rigidly connected to the tower face
 Free-Body Diagram/Equations:
Figures 15 represents two simple free body diagrams showing the wind forces and 
load/moment
from the antenna platform acting on the I-beam. The wind force acting on the 
antenna platform  was calculated using Eq. (1) and the antenna platform moment was 
calculated using Eq. (2).
Antenna Platform Moment:
M  = Fgd Eq. (2)
Fg =  force of  gravity o f  platform
d =  distance from Ibeam to  
platform ' s center o f  gravity
Figure 15. I-Beam free body diagram
 Results:
The results from the FEA stress analysis show a maximum stress of 384 psi. In 
comparison to the
steel I-beam’s yield strength of 29,000 psi, this results in a factor of safety of 
Nrooutge:h Vlyo n7-6M aisneds ,i sd i stphlearceefomree nstt rauncdtu croanllvye sroguenndc.e diagrams can be found in 
Appendix F
13
3. Pulley Housing Stress Analysis
The floor of the pulley housing experiences a great deal of force since the weight from all 
six antenna
platforms and counterweights are acting on the pulleys bolted onto it. FEA, through Creo 
Simulate, was  used to determine if the housing design was structurally feasible and, if so, the 
optimal floor thickness that  would provide a factor of safety of 6.
 Known:
The floor geometry, pulley housing material (ASTM A572 – 65) and 
platform/counterweight loads  are known information necessary for analysis of the 
pulley housing floor.
 Assumptions:
1. Forces from wind loads are negligible
2. Platform/Counterweight load is perfectly vertical
3. Pulley housing floor is rigidly constrained at the bolted flanges
 Free-Body Diagram:
Figures 16 represents a free body diagram showing the force locations from each 
of the six  counterweight/pulley systems. The X represents a vertically downward 
force.
Figure 16. Pulley housing floor free body diagram
 Results:
After simulating the stress in the housing floor with five different floor thicknesses, 
the optimal
thickness was found to be 9/16”. Table 4 shows the simulation results and 
corresponding factors  of safety. This thickness resulted in a maximum stress of 
roughly 7,700 psi and a corresponding  factor of safety of roughly 8.5. Table 5 shows 
the simulation results for each thickness and  corresponding factors of safety.
Wall Thickness (in.) Max Stress (psi) Factor of Safety
3/8 40,470 1.61
7/16 26,890 2.42
1/2 14,225 4.57
9/16 7,700 8.44
5/8 4,350 14.9
Table 5.Pulley housing floor stress analysis results
Note: Von-Mises, displacement and convergence diagrams can be found in 
Appendix F
14
3. Production and Cost Analysis
This section discusses intended manufacturing and assembly procedures for our design 
along with a cost  analyses that provides an estimated payback period on the tower’s initial 
investment.
1. Cost Analysis
A detailed cost analyses was conducted to determine the payback period of the initial 
investment for our  tower design. The cost estimation of the design was broken down into 
material, manufacturing/assembly,
servicing, and insurance costs. The following assumptions were made for cost estimations:
1. The cost for the fabricated steel sections were estimated at a rate of 600$/metric 
ton of ASTM  A572 – 65 high strength low alloy steel
2. The insurance cost for coverage on the tower and location site is estimated to be 
$250,000.
3. The rental rates for the trailer and crane were received from a rough price quote from 
a local heavy  equipment supplier.
4. The operating rates for the manufacturing process is estimated after consulting 
several workers
employed in the industry.
5. The prices for all purchased (off the shelf) parts are based on quotations received 
directly from  suppliers.
6. The overall savings on the project was calculated based on data obtained from  
wirelessestimator.com (aTsy pseu gogf eCsotsetd by project sApmonosuonrt) (.$)
Table 6 shows a breakdown of tMhea tteortiaall  cCoosstt for the tow$e1r 4d1e,s0i3g8n.. 4A0 detailed breakdown, 
along with a list  of all pMaartnsu/mfaacttuerriinalgs/,A csasne mbeb lfyo uCnodst in Ap$p4e,6n5d1ix.0 D0.
Tower Servicing Cost $134.00
Insurance Cost $250,000
Total Cost/Investment $395,823.40
Table 6. Total cost breakdown
The payback period of the tower’s initial investment is an important metric of costing and 
overall design  success. It is defined as the length of time required to recover the initial 
investment. The payback period  was calculated using Eq. (3) and Table 7 which lists 
estimated sources of income from the tower design.
Total Investment  
Payback Period = Eq. (3)
Total Income per Year
Income Source Rate ($/month) Income ($)
Carrier Lease (6 Carriers) $1500 $108,000
Advertising $1000 $72,000
Total Income per Year $180,000
Table 7. Tower income
Payback Period =  2 years  and 3 months
In addition to the payback period of the initial investment, an important cost metric for the 
design is how it  stands against existing monopoles of similar size. Table 8 shows estimated 
cost savings per year.
15
Cost
Estimated Savings ($)
General Liabilities Coverage $1,000,000  
Umbrella Coverage $2,000,000
Statutory Workers Compensation
$28,288
Coverage for Property of Others $4,000  
OSHA Fines from Fatalities and Injuries $125,000
Total Estimated Savings $3,157,288  Table 8. 
4.3.2 Manufacturing Details Estimated Savings
This section discusses intended manufacturing operations for custom components of the 
tower’s design  which includes the tower structure, guide shoe, pulley housing, countertwfoeright 
and the antenna pla m.
Tower Structure Manufacturing
The tower sections are thin walled members and will therefore be manufactured from sheets 
of steel. The
sheet will be cut into a slight trapezoid shape to allow for the taper of the cross-section of the 
tower. The  trapezoid will be cut to length (height of the desired section), with the top and 
bottom sides supplying the  perimeter length of the tower section along with a 3 inch overlap 
for the weld to close the section.
The channels where the guide rail will later be attached will then be pressed into the sheet in 
their respective  locations. The sheet will then enter a metal break to be bent to 60 degrees, 
thus creating the hexagonal  cross section of the structure. The remaining overlap will then 
be stick welded to close the tower section  to insure a strong bond.
The external flanges begin as steel extruded to a 1” X 8” cross section. This stock will be cut 
to a length  matching the perimeter length between the guide slots on the tower section it is 
to be mated with. The work  piece is then bent 90 degrees lengthwise along its center, then 
60 degrees at the midpoint of its length,  matching the corner of the section. Holes are then 
drilled into the outer flange surface to allow them to be  bolted together during assembly.
Guide Shoe Manufacturing
The guide shoe will be a cast product. Steel will be poured into a plaster mold designed 
to specified  dimensions. The resulting finish of plaster casting is relatively smooth and will 
likely not require machining.
This will, however, be confirmed to insure the proper alignment of the wheels that are to be 
later attached.  Once the casting is finished, holed will be drilled to allow the wheel assembly 
to be bolted to the guide shoe
in their respective locations. The wheels and bearings are purchased parts that are fixed to 
the guide shoe  via short bolted axles.
Pulley Housing Manufacturing
The floor of the pulley housing is made up of a steel plate that is die pressed to the specified 
geometry so
the pulley assemblies can be mounted to their respective locations. The remaining portion of 
the pulley  housing (same manufacturing procedure as the tower structure) is welded onto 
the steel plate floor. The  purchased pulleys are bolted onto the floor.
16
Antenna Platform Manufacturing
The curved steel tubes of the antenna platform begin as standard steel pipe and are bent to 
the specified
radius. Flanges are welded onto the end of each curved tube. The antenna mounting pipes 
are simply  standard steel pipes cut to specified length. The tubes are connected together 
via brackets and U-bolts.  The two platform arms are made of I-beams with two plates 
welded on at each end. Holes for the bolted  connection are drilled into each plate as one 
side is attached to the flanges of the rounded tubes and the  other side is attached to the 
guide shoe.
3. Assembly Details
The following steps outline the tower’s general assembly process:
1. The concrete tower foundation is poured to the depth and size specified by the size 
of the tower  to be installed. The base consists of concrete and rebar structure to 
give strength and support
to the concrete pad. Conduits are utilized to bring the power and signal carrying 
wires to the  center of the tower from the external control box.
2. The drive housing section of the tower is bolted to the concrete base and the 
required electrical  lines are installed. The gearless motors are bolted to the base of 
the tower in their respective  locations and necessary electrical connections are 
made.
3. The buffers are bolted into the ground directly underneath where the antenna 
platforms would  land.
4. A crane is used to lift the remaining sections atop the lower sections. The sections 
are bolted  together on their flanges. After section 2 is bolted in, a crane will fix 
each antenna platform into  place on the guiderail.
5. When the top section is installed it is propped up on spacers allowing the required 
clearance to  spool the lifting cables down the interior of the tower to the winding 
drums. A temporary  scaffolding is mounted near the top of the tower to allow 
technicians to guide the cables and  attach the counterweight. The cables are lifted 
to the top of the tower using the crane and the  counterweights are attached to the 
cables to their proper positions as the cables pass over the  pulleys. The lower part 
of the cable is attached to the winding drum and wound about the drum  to insure 
good connection before the weight of the antenna platform is on the cable. When 
the  cables are secured the spacers are removed and the top section is bolted to the 
tower.
17
5 CONCLUSIONS, RECOMMENDATIONS & FUTURE WORK
After conducting multiple stress analyses on critical components and an overall detailed 
cost analysis,
results point towards the conclusion that the design is feasible and development efforts 
should be further  pursued. The tower’s design was capable of bringing together numerous 
existing parts, mainly associated  with the common pulley/counterweight elevator system, to 
create a system that will eliminate the risk of  death or injury while servicing 
telecommunication towers. This added safety feature significantly reduces  high insurance 
costs currently associate with communication towers. With ample advertisement and carrier  
leasing space available, the tower’s design is capable of generating large amounts of income, 
thus making  up for the higher initial investment costs.
Referring back to the customer requirements (listed in Table 1), the tower’s design meets 
most specified  requirements. Major requirements, including ‘safe to service’, ‘capable of 
supporting at least five carriers,  and ‘isolated carrier maintenance’, have all been met. 
Certain requirements, including ‘remote antenna  control’ and ‘deliver power to 
communication equipment’, still require further designing, but incorporation  into the current 
design should not be an issue. In addition, another failsafe incorporated into the design  
would be highly recommended. One potential location for an additional failsafe would be a 
friction brake  located in the platform’s guide shoe.
The next step to take with this design is to conduct further testing via prototyping. It would 
be best to build  a full scale model of the tower and have it exposed to harsh environments 
that these towers will need to  endure. Since this tower is heavily influenced by the 
conventional elevator, it is recommended that  professional elevator engineers are hired to 
oversee the prototype stage of design. Civil/structural  engineers should also be hired to 
ensure that proper foundation and overall structural requirements are  met. Further 
development of the design will result in a well optimized tower that would surely be an  
attractive alternative to the conventional monopole currently in the telecommunication 
industry.
18
REFERENCES
1) Elevators (Third Edition). By F. A. Annett, McGraw- Hill Book Company
- Provided us with majority of the inspiration on our tower’s lift system design
2) Larry Jordan (CEO of SAT Corp.)
- Provided us with design feedback and helped establish majority of our 
customer requirements
3) Hollister Whitney
- Provided us with information/specs on counterweight/frame
- http://www.hollisterwhitney.com/
4) McMaster Carr
- Provided us with information/specs on pulleys, cable, wheels and bolts
5) Oleo
- Provided us with information/specs on elevator buffers
- http://www.oleoinc.com/products/elevator
6) Wireless Estimator
- http://www.wirelessestimator.com/breaking_news.cfm
- Provided us with majority of the information on communication towers
7)   XINDA
- Provided us with information/specs on gearless motor
- http://www.xindasz.cn/
19
B.4 – Collapsible Arm System
Description:
This system consists of several levels of mechanical arms that surround the tower. 
Each arm  belongs to a specific broadcaster and provides 360 degrees of signal. 
When it is necessary to  lower a specific broadcasting arm, the arm folds in several 
different calculated locations to collapse  the arm to a size that can fit inside of the 
other arms without any interference. Each level will ride  on its own specific track 
that will carry it up and down the tower when the arm is collapsed.
Sketch:
B.5 – Suspended Tier Design
Description:
This design is a series of tiers supported from above by several rigid vertical arms, all 
connected  to a structure at the top of the tower. The tiers are located at different 
levels and they get  progressively smaller going down the levels. This allows for each 
tier to fit around all of the tiers  below it, and the individual levels allow for full 360 
degree coverage. When an individual tier  needs to come down for maintenance, a 
transporting device travels to the selected tier and  supports the tier from below. The 
upper supports disengage and the tier is allowed to travel  down the tower. The size 
of the tiers can either increase or decrease going down the tower,  depending on the 
benefits of each scenario.
Sketch:
22
6. – Rotating Antenna Tier
 Rotating Antenna Tier 
 Description:
This design incorporates several tiers or levels of rotating antennas. There are 9 
antennas on  each tier that broadcast a range of 40 degrees a piece. The tiers, 
however, are divided into 10
sections: 9 antennas and 1 open section. This open section provides the space for 
individual  antennas to move up and down the tower. When maintenance is 
needed on a specific tier, the
tier will rotate and, one by one, align each antenna with the transporting track, 
where it can travel
down the tower to be serviced.
Sketch:
23
B.8 – Foldable/Expansion System
Description:
The tower here is hexagonal shaped. Each tier is designed in such a way that it can 
completely  expand from its triangular shape to a completely horizontal beam and 
be brought down from a  side of the tower. There is a traveler for each tier on a side 
of the tower.
There are electro mechanic locks and hydraulics involved to ensure proper 
expansion/folding of  the mechanism to bring it up and down the tower safely. The 
main holding arm which is housed  on the traveler is a hydraulic enforced 
telescoping arm that can expand and retract. It is  designed such to ensure the tier 
being brought down does not interfere with the other tiers.
The traveling mechanism here is a bunch of rollers housed in a bracket. The system 
is hydraulic  in nature and this is what drives the rollers. The mechanism is 
controlled from the bottom of the  tower by an operator/technician.
This provides great deal of accessibility considering each individual tier can be 
brought down  without interrupting operation of the others. Maintenance runs will 
bSeke vtcehry:  quick if all the steps  are properly followed by the operator/technician.
25
B.9 – Exterior Lifting System
Description:
The individual antennas can be sent up the traveling system like on a conveyor 
belt. The  travelling system is on both sides of the main central monopole structure. 
The antennas can be  sent up and brought down from either side based on their 
position on the structure.
The travelling system is on the main central monopole structure and also on each of 
the  individual tiers housed on the monopole. The arm about which each antenna is 
mounted has  degrees of freedom in the spherical coordinate system and can be 
remotely controlled from the  ground by the operator/technician to align the 
antenna is the desired orientation.
The limitations to this design are that the antennas would have to be wireless 
and also be  powered by solar or a wireless medium. Another limitation is that, in 
some cases, multiple  antennas on the same tier would have to be brought down 
dSukeritncgh :a single maintenance run,  even if the run is scheduled only for one 
specific antenna.
B.10 – Concentric Rings
Description:
The use of concentric rings that attach to the tower at two points along a track 
system. The track  system raises and lowers the rings. The workings of the track 
system will most likely be a simple  chain-pulley system powered by an electric 
motor at the bottom. The rings would be lowered  independently, the antennas 
serviced, repositioned and then sent back up.
Sketch:
26
B.11 – Rotating Collars
Description:
There will be a track system to send the brackets that hold the antennas up and 
down. There is  rotating collars at predetermined heights along the tower. The 
bracket to hold the antennas will  be connected to the tower by two points of 
contact for stability.
Sketch:
B.12 – Spiral Track
Description:
There will be a track that wraps around the tower letting the brackets that hold the 
antenna to get  up to the collars that allow them to set their azimuths.
Sketch:
27
B.13 – Overlapping Platforms
Description:
There are four tracks on the tower. There are four platforms that can hold one 
antenna each.  The loops are all differing diameters, letting the antennas be 
lowered and serviced  independently.
Sketch:
B.14 – Antenna Retriever
Description:
There is an inner antenna retriever that sends the antenna up to a set cut out 
portion of the  tower and it pops through the tower. The antenna would not be 
able to change azimuths.
Sketch:
28
B.15 – Multiple Towers
Description:
There is a circular array of “towers” (bars) that each house a track and can hold 
one antenna.  The circular array of bars will need to have a circular ring on the 
inside to support the bars in a  vertical orientation.
Sketch:
B.16 – The Willow Tree
Description:
This design incorporates long cables supporting each tier of antennae at its 
respective height.  The tiers are circular and each of different radius allowing them 
to pass by each other so they  can be lowered independently. The top and bottom of 
the tower would have fixed guides for the  cables and pulleys to direct them back to 
the center of the tower. At the base of the tower some  sort of transmission could 
deliver the power to mobilize the tiers. Coarse azimuth adjustment  would be carried 
out on the ground but fine tuning would be remote controlled motors at each  
antennae.
Sketch:
29
B.17 – Circular Tiers
Description:
The towers would have a fixed c-shaped frame at the predetermined heights were 
the  antennae’s are desired. The gap in each tier would align with the other gaps 
and mounted on  the tower in that gap would be the lifting mechanism for the 
antennae frame segments. The  antennae would be mounted to the segments on 
the ground and then elevated to their  respective tier. Another mechanism at each 
tier would rotate the segment onto the fixed frame.  Again coarse azimuth 
adjustment would be carried out on the ground but fine tuning would be  remote 
controlled motors at each antennae.
Sketch:
B.18 – Fixed Collapsible Frame Segments
Description:
Each tier would again have permanent supports around the portion of the tower that 
does not  contain the elevating mechanism. The structures that hold the antennae’s 
will be three sided  figures that are collapsible into triangles. When the structures are 
“folded” they can then be  translated around the tower to the elevating mechanism. 
The design of the fixed framing of each  tier allows the folded structure to pass 
without disturbing the lower towers. Corse azimuth  adjustment would be carried out 
on the ground but fine tuning would be remote controlled motors  at each antennae.
Sketch:
30
APPENDIX C – Supplier Specification Sheets
C.1 – Guide Shoe Wheel (Supplier: McMaster Carr)
C.2 – Guide Shoe Wheel Axle (Supplier: McMaster Carr)
31
C.3 – Mounted Pulley (Supplier: McMaster Carr)
32
C.4 – Steel Wire Cable (Supplier: McMaster Carr)
33
C.5 – Hydraulic Buffer (Supplier: Oleo)
34
C.5 – Gearless Motor (Supplier: XINDA)
35
C.6 – Counterweight Frame (Supplier: (Hollister Whitney)
36
APPENDIX D – Detailed Cost Breakdown (Bill of Materials)
1. Material Costs
1. Tower Structure
*The tower sections listed below are fabricated using ASTM‐A572‐65, High Strength Low Alloy
Steel.
Qty Item Description Mass Unit Price Cost 
 (#)   ($ / lb)  ($)
(lbs)
1 Tower Section I 5650 0.27/ lb $1,537.7
1 Tower Section 2 29891 0.27/ lb $8,135.1
1 Tower Section 3 21793 0.27/ lb $5931.1
1 Tower Section 4 15247 0.27/ lb $4,149.5
1 Tower Section 5 12091.5 0.27/ lb $3,290.8
1 Tower Section 6 9225.12 0.27/ lb $2,510.7
1 Tower Section 7 6614.9683 0.27/ lb $1,800.3
1 Tower Section 8 2041.0037 0.27/ lb $555.8
6 Section 2 I –Beam W14 x 90 23500.0 0.27/ lb $38,070.0
6 Section 3 I –Beam W14 x 90 12533.76 0.27/ lb $20,304.7
6 Section 4 I –Beam W14 x 90 915.1 0.27/ lb $1,482.5
6 Section 5 I –Beam W14 x 90 762.5665 0.27/ lb $1,235.4
6 Section 6 I –Beam W14 x 90 610.053 0.27/ lb $988.3
6 Section 7 I –Beam W14 x 90 457.54 0.27/ lb $741.2
TOTAL COST $84,738.6
D.1.2 Bolts
*The below listed bolts are all ASTM A307 grade A Hex bolts.
Qty Item Description Unit Price Cost 
 (#)  ($/item)  ($)
30 Sections 1-2 Flange Bolts 2 ½” $0.55 $16.5
30 Sections 2-3 Flange Bolts 2 ½” $0.55 $16.5
30 Sections 3-4 Flange Bolts 2 ½” $0.55 $16.5
30 Sections 4-5 Flange Bolts 1 ¾” $0.40 $12.0
30 Sections 5-6 Flange Bolts 1 ¾ ” $0.40 $12.0
30 Sections 6-7 Flange Bolts 1 ¾” $0.40 $12.0
30 Sections 7-8 Flange Bolts 1 ¾” $0.40 $12.0
432 I-Beam Bolts ½” - 13 $1.10 $475.2
TOTAL COST $572.7
37
D.1.3 Antenna Platform Assembly
Qty Item Description Unit Price Cost 
 (#)  ($/item)  ($)
12 Guide Shoe Housing $22.95 $275.4
Custom Built - ASTM-A572-65
96 Rollers $22.14 $2,125.4
Nonmarking Polyurethane Wheel 4”
96 Wheel Axles $2.26 $217
w/o Grease Fitting, ½” Diameter, 3” Length
12 Steel Eye Bolts $8.40 $100.8
w/ Shoulder for Lifting,¾” - 10 Thread Size
84 Guide Shoe Bolts $1.10 $92.4
ASTM A307 grade A, Hex, Thread Size ½”-13
30 8 ft Mounting Pipe $25.00 $750.0
A500 Carbon Steel, 1¼” Diameter
18 Tubular Semicircular Platform $60.00 $1,080.0
A500 Carbon Steel, 2” Diameter
8 Tubular Flange Bolts $1.10 $8.8
ASTM A307 grade A, Hex, Thread Size ¾” - 10
18 Guide Shoe Platform Bracket $8.00 $144.0
A500 Carbon Steel
1 U- Bolt for 1¼“ Pipe $5.30 $5.3
304 Stainless Steel
1 U- Bolt for 2” Pipe (Extra Long) $7.45 $7.5
304 Stainless Steel
12 Platform I-Beam Arm $25.38 $304.6
Structural A36 Steel Wide Flange
TOTAL COST $5,111.1
D.1.4 – Drive/Lift System
Qty Item Description Unit Price Cost 
 (#)  ($/item)  ($)
6 WWTY Gearless Traction Machine  $2,581.00 $15,486.0
800 kg, 1 m/s speed, 2:1 traction 
ratio
6 Counterweights $2,475.00 $14,850.0
Lead Filled Counterweights, MARS Metal
12 Mounted Pulleys + Axle $511.00 $6,132.0
Heavy Duty Steel w/ Easy turn bearings, 6”
6 Buffers $300.00 $1,800.0
SEB 18, Gas Hydraulic Buffer, Oleo 
International
12 Cables $1,029 $12,348.0
Steel Rope, High Strength, 3/8”diameter – 
420ft
TOTAL COST $50,616.0
38
D.2 – Manufacturing/Assembly Costs
Item Description Rate Operating Cost 
 Hours   ($)
(day/hr)
Welding – Hand Welding Operator w/ consumables $66/hour 8 hours $530.0
Sheet Metal Bending $10/hour 2.5 hours $25.0
Bolting $16/hour 6 hours $96.0
60 ft Trailer (6 trips) $1500/day 1 day $1500.0
300 ft Crane $2500/day 1 day $2500.0
TOTAL COST $4,651.0
D.3 – Tower Servicing Costs
Item Description Rate Operating Cost 
 Hours  ($)
1 Telecom Technician $18.5/hour 2 hours $37.0
1 Service Truck + Equipment $30/day 1 day $30.0
Total per Service/Upgrade $67.0
TOTAL COST/YEAR $134.0
D.4 – Insurance Costs
Item Description Cost ($)
Insurance Coverage for Tower + Property $250,000
APPENDIX E – Design Drawings
PDF files of design drawings have been attached to 
this report
39
APPENDIX F – Analysis Results
F.1 – Tower Analysis  
Von Mises Fringe Plot
Displacement Fringe Plot
40
F.2 – I-Beam Analysis
Von Mises Fringe Plot
Displacement Fringe Plot
41
F.3 – Pull Housing Floor Analysis
Von Mises Fringe Plot
Displacement Fringe Plot
42