CNS 4-30-10b Lunar Navigational System

8/13/2019 CNS 4-30-10b Lunar Navigational System

http://slidepdf.com/reader/full/cns-4-30-10b-lunar-navigational-system 1/18

CENG4625 Senior Projects – Semester 2

Adam Almaguer, Juan Flores, Thomas Ives,

and Omar Sanjak

April 30, 2010

Celestial Navigational System



Agenda

• Background

• Project Motive

• Objectives

• Requirements

• System Functionality and Components

• System Simulation

•Conclusion

2



Project Motive

• Current NASA navigational plans :

– constellation of expensive satellites – 30 meter accuracy

– Limited to large celestial bodies

•Our navigational system plan: – Provide an inexpensive alternative

– provide one meter accuracy position location forsurface activities

– Useful in any environment with a solid surface

3



Objectives

4

Navigation

System

Inexpensive

Portable Easy to use

COTS Parts

Accurate

AccommodateEMU limitations

Simple Design

Lightweight

RechargableBattery

Limited Controls

Low Power Usage

Large coverage

Durable

Shock Resistant

Dust Resistant

Radiation Shielded

Space Temperature

Zero Gravity

Simple Setup

Informative Output



Requirements

• Customer Requirements –

System can be used on Mars, and other celestial bodies – Hardware should consume little power and be

rechargeable

– Receiver unit is easy to use

• Engineering Requirements – Hardware must be enclosed to deter foreign particles

from affecting internal and external components

– Hardware can be charged using more than one method

– Receiver screen output should identify itself and allbeacons within its detection range

5



Requirements (Cont.)

There are several engineering requirements that our group will not beable to implement for the prototype because we do not have a way oftesting them. They are:

1. Hardware must be built to withstand cosmic radiation andmicrometeorites -This is usually done in a closed lab where componentsare bombarded with radiation and high velocity projectiles

2. Hardware will be able to function in zero gravity - We would need to testthe hardware in a near zero gravity environment like an airplane followingan elliptic flight path relative to the center of the Earth.

3. Hardware must comply with the flammability requirements of NASA-STD-6001, “Flammability, Odor, Off-gassing, and CompatibilityRequirements and Test Procedures for Materials in Environments ThatSupport Combustion” – We would need access to a laboratory in order toconduct Determination of Off-gassed Products and Total Spacecraft Off-gassing Tests

6



Navigation Concept• Automated Survey

– Beacons transmits angle to Receiver

• Beacon zero-angle identified

• Beacon rotates clockwise

– Receiver calculates Beacon angles

• Angles between beacons provided

– Receiver calculates distance to beacons using

triangulation• Build Database

– Record Beacon info (ID, distance between

beacons, zero-angle direction, health)

– User specified locations

• Periodic Re-Survey – Beacon angles re-measured

– Beacon distances re-measured

– New specified locations recorded

R

A

B

D

C

0°

0°

0°

0°

0°

∠R0B ∠R0A∠R0D ∠R0C

7

W

X

Y

Z



8

Beacon Circuit

Reset

12 8

224

Counter(74LS93)

ID Switch

4

5V

16

Preamble(AAAAH)

Parallel to Serial (74165)

Motor Assembly /w

Photo Interrupters

÷2

÷2 ÷416MHz CLK

Prism /w Lens

Buffer

Buffer

Buffer

Laser

PSK Signal Modulator

Buffer

16MHz8MHz

2MHz

30M Distance



9

Beacon Message

Message (48 bit)

F r e e

( 8

b i t s )

G u a r d

( 2

b i t s )

G u a r d

( 2

b i t s )

Extra (16 bit)

Preamble (16 bit) ID (8 bit) Angle (12 bit)



ID

PLL Demodulator

(NE564)

Clock

Data

12UART

(IN58250N)

16

Serial toParallel

(74LS299)

/w Word

ComparePreamble Data Good

8

Angle

Baud

CLK

Navigation

Computer

(Propeller)

RS232112Kb/s

Photo Diode

Display

DC bias

Circuit

DC Blocking

Filter

Amplifier

(OPA37)

Receiver Circuit

10



Receiver Microcontroller

Runs at 3.3V

8 32bit CPUs32 I/O pins

One Video Generator per Core

Programmed in SPIN or PASM

32KB RAM and 32KB ROM

11



Receiver Process

12

Inputs to Receivers Calculations Outputs User: Range of beacon Distances between

beacons

Set values to variables for

future calculation. Visual representation of each

beacon and its location from

the others.

Beacon Message: 16-bit preamble Beacon ID Beacon Rotation number 8-bit message postamble

or Beacon Health 2-bit data separators

Verify that message is accurate

(using Message format ) Compare message with

previous ones to get enoughinformation about current

location.

Visual interpretation for

location of the receiver



- 8 m

1

3

2

Latitude

(-2. -.3)

- 24 m

Longitude

24 m

(-2 , 1)

56 m

(-2, 2.3)

RECEIVER DISPLAY

Vector

88 m120 m152 m

(-2, 3.6)(-2, 5)(-2, 6.3)

-5 -4 -3 -2 -1 0 1 2 3

6

5

4

3

2

1

0

13



Conclusion (Cont.)

• References

– NASA, “The Vision for Space Exploration,” Tech. Rep. NP-2004-01-334-HQ, NASA, Washington, D.C., 2004

– Schier, James. “NASA’s Lunar Space Communication and

Navigation Architecture,” American Institute of

Aeronautics and Astronautics- 092407, NASA HQ,Washington, D.C., 2008

15



16

Additional Slides



17

Phase Lock Loop (PLL) Demodulator

Phase

Detector

VCOBPF

(2MHz)

Schmitt

Trigger

FSK in

(8/16MHz)Data out (2MHz)

Clock out (16 MHz)

PLL

CNS 4-30-10b Lunar Navigational System

Documents

Transcript of CNS 4-30-10b Lunar Navigational System