This document describes a remote controlled tree trunk climbing device. The goals are to enable applications that can help humans by moving up and down tree trunks. It uses an RF module, battery, DC motors, and a climbing unit with spring-loaded wheels. The RF module transmits signals to control the motors which power the wheels via shafts. Calculations were done to determine the optimal wheel diameter, motor RPM, and time to climb a tree of a given height and weight. The advantages are its light weight, low cost, use of rechargeable batteries, and ease of use. The main disadvantage is its inability to move sideways.

1. TREE TRUNK CLIMBING DEVICE
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2. PROJECT GOALS:
ABSTRACT
 The objective of this project is to construct a remote controlled
device that can move up and down on a tree trunk which can thus enable
various further applications in future which will be useful to man in various
ways.

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3. BLOCK DIAGRAM:
BATTERY BATTERY
DC CLIMBING
RF
SERIES UNIT
MODULE
MOTORS
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4. WORKING COMPONENTS:
 RF module with a battery
 DC series motors with battery
 Climbing unit with spring loaded wheels
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5. RF MODULE:
 Radio frequency is an electromagnetic wave frequency between the audio
and infrared.
 Its in the range 30kHz to 300GHz.
 It corresponds to the frequency of electrical signals normally used to
produce and detect radio waves.
 RF unit used is of the capacity 40MHz.
 The unit is taken from a toy car.
 In order to increase its range an Ariel is used.
 RF unit is of 2 components: RF TRANSMITTER,
RF RECIEVER.
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6. RF TRANSMITTER:
 RF transmitter is to modulate, up convert, and amplify signals for
transmission into free space. An RF transmitter generally includes a
modulator that modulates an input signal and a radio frequency power
amplifier that is coupled to the modulator to amplify the modulated input
signal. The radio frequency power amplifier is coupled to an antenna that
transmits the amplified modulated input signal. Power amplifiers are
required in radio telecommunication systems to amplify signals before
transmitting, because a radio signal attenuates on the radio path. For
efficiency, the amplifier is often a non-linear amplifier operated near its
peak capacity.
 RF receiver holds the job of receiving the modulated signal and then
demodulating the particular signal to output signal; thus giving instructions
to the exterior on accordance to it.
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7. BATTERY:
 S M F Battery is being used here.
 Its capacity is featured as: 12V, 7Ah.
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8. DC SERIES MOTORS:
 Total no of motors :2
 Total capacity : 28W
 Distributed as : (14+14)W
 Motor rpm determines the wheel diameter
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9. CLIMBING UNIT:
 2 separate spring loaded wheels
 Spring pressurizes the unit to the tree
 Spring adjusts the unit according to the varying diameter of the tree
 Pipes employed at either parts of the unit to avoid path difference
 Chassis for further attachments
 Chassis also has RF module, 2 motors,1 battery etc.
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10. OPERATION PROCEDURE:
BATTERY RF MODULE
BATTERY DC MOTORS
VIA SHAFTS
WHEELS
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11. STRUCTURE LAYOUT:
B
RFR
S S
M
M
R F T

12. COMPONENT IMAGES:
 WIPER MOTOR
: 14W
12V
44 rpm

FIG NO:01
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13.  SPRING
Mean diameter of coils, D
:24mm
Wire diameter, d :2mm
No. of coils, n :85
Spacing index, c :D/d
=12
Stiffness, k :F/ defl.
=G(d)^4/8(D^3)n
=1.24N/mm
FIG NO: 02
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14.  WHEELS
Diameter of wheels,
d: 6mm
FIG NO: 03
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15. RF TRANSMITTER & RECEIVER:

16. CALCULATIONS INVOLVED:
 Total mass estimated, m : 10 kg
 Total height estimated, h : 20m.
 Battery capacity : 12V, 7AH
 Motor capacity : 12V,14W,44rpm.
 Total watt used = 14*(no. of motors used)
= 28W.
 Due to 50% of loss assumed = 28/2
= 14W.
 For the height and weight mentioned
time taken, t = (746*h*m)/(W*75)
= 2.5 mins (app.).
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17.  Total rpm = 44*2.5
= 110 rpm.
110 rpm 20m
1 rpm 18cm (app.)
 Diameter of the wheel, d :
(3.14*d) = 18
d = 6 cm (app.)
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18. COMPETITIVE ANALYSIS:
 Strength:
Less weight: Main priority
Less effort and user friendly
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19. ADVANTAGES:
 Less weight: Main priority
 Less cost
 S M F battery is used (Pollution free).
 Less effort and user friendly
 Could be converted to a superior device
 Saves money
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20. DISADVANTAGES:
 Sideways movement not possible
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21. REFERENCES:
Design of Machine Elements : KHURUMI
Design Data : PSG College of Technology,
COIMBATORE