1. DT021/4 Final year project Christophe SCAYA
Surveillance rocket
DT021/4 Final year project
Christophe SCAYA
The name of my …….
14/11/2018

2. Structure of discussion
Aim of the project:
Design a low-cost rocket for ground surveillance
Design an embedded system with a set of sensors and a digitial video camera
Multidisciplinary aspects:
Mechanical concept
Electronics
Computing
Blabla, this gnd surveillance is realised by an embedded blablba
Main interest  multidisciplinary project
Mechanical ++ :
-physical study of a system
-aerodynamical characteristics
Electronics due to the presence of sensors
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3. Part I : The rocket Schematic from the rocket made with catia
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4. What type of rocket ? Preliminary requirements: Principle:
Low-cost materials
Easy to use and reuse
Principle:
Water initially put in a plastic bottle
Pressurised air is then added
A manual system triggers the flight
WATER ROCKET
First question : what type of rocket?
The rocket must be easily product in a big scale
The system allows to release the rocket from its launching system
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5. Stability of the rocket 1/2
Assume a rocket with an initial trajectory.
A disturbance is added and the initial trajectory deviates from a small angle α
CASE 3:
the rocket returns to its initial trajectory
The rocket is stable
GOOD DESIGN !
CASE 1:
the rocket continues to increase the deviation from its initial trajectory
The rocket is unstable
VERY BAD DESIGN !
CASE 2:
the rocket stays on the deviated trajectory
The rocket is neutral
BAD DESIGN
The main source of disturbance : wind
We define the stability as the aptitude of the rocket to recover its initial trajectory
How is it possible to obtain the stable case ?
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6. Stability of the rocket 2/2
Two points influence the stability:
The Centre of mass (Cm)
The Aerodynamic centre (Ac)
The condition to obtain a
stable rocket is to position
Ac below Cm
This is done by correctly
shaping the fins of the rocket
Due to the position of 2 physical points
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7. Recovery system Parachute is located in the nose cone of the rocket
When the rocket reaches its maximal position, a small weight falls and release the cone and the parachute
The parachute can open itself and slowdown the rocket
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8. Part II : Electronics
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9. Objectives
Record physical values from the flight with appropriate sensors
Data are analysed by a microcontroller located in the nose cone
Transmit the data to the ground via an appropriate wireless system
Sensors are connected to the PIC which proceed to ADC
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10. Possible type of sensors
Gyroscope
Measurement : inclination
Interest : monitoring the inclination of the rocket due to the wind effect
Price : €37.90 each (minimum order quantity of 25)
Too expensive :
NOT CHOSEN
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11. Possible type of sensors
Pressure sensor
Measurement : relative pressure
Interest : monitoring the pressure inside the plastic bottle. This value can be used to deduce the force developed by the rocket in flight.
Price : €13 each
Implementation: very difficult to fix inside the rocket
Not easily implementable :
NOT CHOSEN
Relative pressure compared to atmospheric pressure
Type sensor not considerate but very interesting.
If a new project is given to a student that shd be great to include this sensor
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12. Possible type of sensors
Accelerometer
Measurement : acceleration
Interest : monitoring the acceleration of the rocket and then deducing both speed and position
Price : about €10 each
Implementation: on the main PCB
All is good:
CHOSEN
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13. Global implementation
Receiver
To the ground
Max233 convert the signal PIC to comply with the RS232 standard
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14. States of the PIC Power is switched on
Waiting mode:
Power is switched on
Ready for flight:
The ready switch is pressed ; the PIC waits to detect variations in the accelerometer outputs
Flight:
The PIC transmits the accelerometer values via the wireless system
End of flight:
No variation detected from the accelerometer ; return to “ready for flight” state
The main program is divided into different states
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15. Part III : Computing
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16. Data recovery Data sent using the RS232 protocol
Necessary to use software
HyperTerminal can be used in Windows
Very simple to use
Data from the rocket printed on the screen
Not practical to exploit
 Use another special software : RocketSOFT
developped with Java 1.6 and NetBeans IDE 6.0
To get back (récupérer) the data from the serial port
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17. Demonstration
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18. Videos flight
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19. Videos flight First flight : 8th April 2008
Second flight : 10th May 2008
Other flights : 14th May 2008
Flight 1
Flight 3
Flight 4
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20. Thanks for your attention
Putain c’est fini, je suis en VACANCES !!!
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