cltp4 sensor actuator pdf配布用 - uniseccltp4_sensor_actuator.pdf · use case of satellite...

Sensor & ActuatorMasahiko YamazakiDepartment of Aerospace Engineering,College of Science and Technology, Nihon University, Japan

1. What is sensor & actuator? What should we consider?

2. What is sensor & actuator as a satellite? What should we consider? Use case of satellite sensor & actuator

3. What is sensor & actuator as a CanSat What is in CanSat? What should we consider? Design example of sensor & actuator as a CanSat

4. Summary

2 What is sensor & actuator?

Sensor is a device that detects and responds to some type of inputfrom the physical environment. The specific input could be light, heat, motion, moisture, pressure,

or any one of a great number of other environmental phenomena. The output is generally a signal.

Actuator is device that takes energy and converts it into some kind ofmotion. It is operated by a source of energy, typically electric current, fluid

pressure, or air pressure, and converts that energy into motion.

The role of sensor & actuator

The main task of sensor is to detect a satellite condition, e.g. batteryvoltage, solar cell current, thermal and attitude, etc.

The main task of actuator is to control a satellite condition, e.g. orbitand attitude, deployment of solar panel and antenna, etc.

3 What should we consider?

Not only a single body performance but also consider relation withothers. Component performance: Measurement range and accuracy. Other subsystems: C&DH subsystem(data control), Mission & ADC

subsystem(data use), Communication subsystem(data transmit). Peripheral circuit: A/D converter, amp, filter. Component Interface: Serial (UART, SPI, I2C, ...), Discrete

Indispensable components for a satellite

PWM

Seri

al

Structure

Stru

ctur

e4 What is sensor & actuator as a satellite?Bus system and Mission system

Bus System

Mission System

System for survival in space andmanagement of whole system

e.g. experimental module,observation sensor,camera, …

Power subsystem

Communication

Attitude determination and control (ADC)

Command and Data handling (C&DH)

Structure

Thermal control

(Harness)

5

Communication

Receiver Transmitter

Sensor

S1 S2 Sn

voltage, temperature, current, attitude sensors

Command & Data handling

Actuator

ThrusterTorquer

Reaction wheel

Mission Subsystem

SensorExperimental system

Camera etc.

Electrical power supply

Battery

OBC Memory

Uplink Downlink

Solar cell

Solar cell

Structure

Ground Station

UplinkDownlink

What is sensor & actuator as a satellite? What is sensor & actuator as a satellite?6

Ground Station

UplinkDownlink

VoltageTemperatureCurrentMagnetismSun lightAccelerationAngular velocity

Reaction wheelMagnetic torqueNichrome wire

Sensor example

Actuator example


Ground Station

UplinkDownlink

Sensor & Actuator are closely related with C&DH subsystem.― Data communication rate, Sampling interval, Memory size, Control

interval, etc.


Ground Station

UplinkDownlink

Sensor & Actuator are closely related with other subsystemsElectrical power supply, Communication, Structure, Command & datahandling subsystem.― power consumption, data amount(Memory size, sampling interval,

downlink format), operation order, component layout, etc…


-0.4

-0.2

0

0.2

0.4

0.6

0 200 400 600 800 1000 1200

BxByBz

Mag

netic

flux

den

sity

[gau

ss]

Time [sec]

CW started

[Operation order]Magnetic sensor (with radio communication noise)

10 What should we consider?[Components layout]Thermal sensor (Inner and Outer components)

-40-30-20-10

0102030

0 1000 2000 3000 4000 5000 6000 7000

Solar panel 1Solar panel 2Solar panel 3

Solar panel 4Solar panel 5Solar panel 6

Tem

pera

ture

(Cel

sius

)

Time (sec)

Eclipse

Daytime

-40-30-20-10

0102030

0 1000 2000 3000 4000 5000 6000 7000

Li-ion battery #1Gyro # 2

ReceiverDigi-talker

Tem

pera

ture

(Cel

sius

)

Time (sec)

11 What should we consider?[Components layout]Sun sensor (Outer panel of CubeSat)

12+ 0.0- 0.0220.0 [mm]

20100.

+.0

-210.0

[mm]

15148.

+.8

-214.8

[mm]

12 Use case of satellite sensor & actuatorAttitude determination and control subsystem

Attitude determination = determination ofthe directional vector of each body axis

Attitude control = to control the directionalvector to required value

sat sat sat satx y z

é ù= ê úë ûR e e e

13

Attitude determination and control subsystem Attitude determination sensor

For example, extended Kalman filter by using sun sensors, geomagnetic sensors, and gyro sensors

Reference direction

Sensor for attitude

determination

Geomagnetic sensor

Sun sensor

Earth sensor

Star tracker

Attitude motion

Relative position

Angular velocity

Relative angle

Acceleration

GPS receiver

RF sensor

Mechanical gyro

Optical gyro

MEMS gyro

Accelerometer

Position

Field

Use case of satellite sensor & actuator 14

Attitude determination and control subsystem Attitude control actuator

For example, 3 axis control by magnetic torquerInternal force

Attitude control

actuator

External force

Momentum wheel, Reaction wheel

Monopropellant（catalytic hydrazine ）

Control moment gyro

Thruster

Bipropellant (oxidizer and fuel)

Gas-liquid equilibrium thruster

Ion engine

Gravity gradient torque Extensible boom

Geomagnetic torque

Aerodynamic drag

Solar radiation pressure

Magnetic torquer

Permanent magnet

Dragshute

Deployable membrane

Cold gas jet

Use case of satellite sensor & actuator

15

Attitude determination and control subsystem Attitude control actuator

For example, 3 axis control by magnetic torquerInternal force

Attitude control

actuator

External force

Momentum wheel, Reaction wheel

Monopropellant（catalytic hydrazine ）

Control moment gyro

Thruster

Bipropellant (oxidizer and fuel)

Gas-liquid equilibrium thruster

Ion engine

Gravity gradient torque Extensible boom

Geomagnetic torque

Aerodynamic drag

Solar radiation pressure

Magnetic torquer

Permanent magnet

Dragshute

Deployable membrane

Cold gas jet

Solar sailIKAROS

Use case of satellite sensor & actuator 16

Attitude determination and control subsystem A/D converter, Filter and Amp.

Out

put V

olta

ge (V

) x

yz

Out

put V

olta

ge (V

)

x

yz

Low pass filter for gyro sensor


17

Attitude determination and control subsystem Current control.

Pulse width modulation


OBCMemoryData storage

Actuator

ActuatorCurrent control

(PWM, Motor driver)

Control input(digital signal)

Pulse width modulation(PWM) Pulse Width Modulation is a

simple method for controllinganalog devices via a digital signal.It’s a very efficient way to drivemotors.



OBCMemoryData storage

Sensor

Galvanometer

Output voltage(Analog signal)Amp

Filter

AD convertor

Command(Digital signal)

Output voltage(Digital signal)

Actuator

Magnetic Torquer

Current control(PWM, Motor driver)

Control input

Gyro 3axis

18

Attitude determination and control subsystem Ex. De-spin control by Magnetic Torquer



Ground Station

UplinkDownlink

Sensor & Actuator are closely related with other subsystems (Electricalpower supply, Communication, Structure, Command & Data handling) andaffected each other.― power consumption, data amount(Memory size, sampling interval,

downlink format), operation order, component layout, etc…

It is important to extract performance as a system.

It is important to consider the interference between sub-systems

The mission sequence should be imaged well, discussed, and should beshared well in the team.

CanSat?

21 What is in CanSat?Bus system and Mission system

Bus System

Mission System

System for survival in space andmanagement of whole system

e.g. experimental module,observation sensor, camera, …

Power subsystemCommunicationAttitude determination and control (ADC)

Command and Data handling (C&DH)StructureParachute(Harness)

Parachute

22 What is in CanSat?


VoltageTemperatureCurrentMagnetismSun lightAccelerationAngular velocityGPS

MotorNichrome wire

Sensor example

Actuator example


VoltageTemperatureCurrentMagnetismSun lightAccelerationAngular velocityGPS

MotorNichrome wire

Sensor example

Actuator example

Sensor & Actuator are closely concerned with other subsystems (electrical power supply, communication, structure, command & data handling) and affected each other.― data amount(Memory size, downlink format), number of sensor &

actuator, sampling interval(MPU spec), control algorithm, control interval, layout, noise(Filter, Operation), etc…

The desired performance not by itself alone but as a system is required.

Design the sensor & actuator under the consideration of the communication and interaction with other subsystems.


Separation

Autonomous Flight

Launch Ground stationObjective point

Downlink

Uplink


Separation

Autonomous Flight


Downlink

Uplink

The mission sequence should be imaged well, discussed, and should be shared well in the team.

Imagine all the possible events and anomalies which may happen on CanSat and prepare countermeasures for them as many as possible.


Separation

Autonomous Flight


Downlink

Uplink

Step1:Sensor and Actuator selection

Consider requirement(weight, dimension), environmental condition(vibration, acceleration, thermal), flight time, etc…from past experience

Consider Mission Sequence & clarify requirements(1) Set up CanSat and put it into a rocket and turn on switch A.

(2) Rocket side prepare launch(you cannot contact and not predict the time)

(3) Launch with high acceleration(CanSat may measure something in a rocket and write in memory)

(4) CanSat Starts certain operation triggered by some switch at the timing of release from the rocket.

(5) Downlink mission data as well as write in memory.

(6) Landing may trigger also another actions….


Sensoring: to be detected considering what kind of sensors are available and how easy to implement―Temperature, Pressure, GPS, Accelerometer, Sun light, Gyro, Ultra violet, Sound, Infra red,…

Actuation: available actuators, power, force, etc…―Motor, Nichrome line to cut nylon wire, Magnet, Utilization of shock of landing, Spring, Gravity,…

High level actions: combination of sensor, actuator & other systems―Guidance/control with GPS(comeback), camera, stand up, moving a er landing,…

Step1:Sensor and Actuator selectionWhat kind of sensors & actuator are available. How easy to implement―Spec(How accurate?, How often?), Environmental tolerance, Powerconsumption, Data form(Digital/Analog) and Interface(I2C, Serial, UART),Size, Weight, Operating voltage… ）


Direction control start!

Mission Example

Parachute separation!

30 What should we consider? Mission Example

Release from the Rocket

Launch!

Parachute deployment

Power ON

Save sensor data(GPS & Pressure)

Altitude <=1600ftParachute release

(Pressure & Nichrome wire)

Parafoildeployment

Direction control(Servo Motor & GPS)

Landing

Parachute separation!

Direction control start!

31 What should we consider? Mission Example


Launch!


Power ON



(Pressure & Nichrome wire)

Parafoildeployment


Landing



Actuator

Sensor


OBCEEPROM Servo Motor

GPS

Relay switch

Nichrome wire

Battery 3.7V

5V Regulator

3.3V Regulator

Parafoil

Battery 3.2V

Parachute

5V line

Data communication line

Other line

Pressure

3.2V line

Battery 3.7V CommunicationReceiver Transmitter

3.7V line

PWM

Flag

Serial communication


3.3V line



Actuator

Sensor



GPS

Relay switch

Nichrome wire

Battery 3.7V

5V Regulator

3.3V Regulator

Parafoil

Battery 3.2V

Parachute

Pressure


PWM

Flag



5V line


Other line

3.2V line

3.7V line

3.3V line

34 What should we consider? Analog Sensor with A/D converter, Filter and Amp.

Digital Sensor

35 What should we consider? A/D converter

A/D converter convert analog data from sensors

into digital data. 10bit A/D converter can express

analog data into 10bit digital data. In case of reference voltage is

5V…0V →「0000000000」3V →「1001100110」5V →「1111111111」

0V~5V is expressed in 210=1024steps.

36 What should we consider? Serial & Parallel communication

01011110

01011110

0 1 0 1 1 1 1 0

sending side receiving side

CLK Line Data Line

b7b6b5b4b3b2b1b0

b7b6b5b4b3b2b1b0

input output

1

0

0

0

1

01

1

1 0 1 0 0 1 0 1

Serial communication(I2C,UART,SPI,…) Serial communication is a process of

sending data one bit at a time,sequentially.

Parallel communication Parallel communication is a process

of sending data several data signalssimultaneously over several parallelchannels.

37 What should we consider? Servo motor

Pulse width modulation

Pulse width modulation(PWM) Pulse Width Modulation is a

simple method for controllinganalog devices via a digitalsignal. It’s a very efficient wayto drive motors.

38 What should we consider? Servo motor

【Sample Program】 1. #include<16f877.h> 2．#fuses HS, NOWDT, NOPROTECT, PUT, BROWNOUT, NOLVP 3．#use delay (CLOCK = 10000000) 4．void main() 5．{ 6． int i; 7． while(1) 8． { 9． for(i=0;i<10;i++) 10． { 11． output_high(pin_b3); 12． delay_us(1500); 13． output_low(pin_b3); 14． delay_us(16500); 15． } 16． } 17．}

V+

0V

Pulse width =1500us

Period=18000us

39 What should we consider? Nichrome wire to cut nylon wire

+3.2V

D1DIODE

+

-VcSW1STTL

PIC in

+V5V

Q1PNP

WireNichromR2

1k

Relay drive circuit

PIC signal Relay switch condition

High OFF

Low ON

Nichrome wire with Relay drive circuit PIC’s high/low signal can control the

relay switch condition(On/OFF).

Separation!

40 What should we consider?Step2:Sensor and Actuator Assembly:System design & Operation check(Sensor & Actuator spec check)―Spec(How accurate?, How often?), Environmental tolerance, Power consumption, Data form(Digital/Analog) and Interface(I2C, Serial, UART),Size, Weight, Operating voltage… ）


Actuator

Sensor



GPS

Relay switch

Nichrome wire

Battery 3.7V

5V Regulator

3.3V Regulator

Parafoil

Battery 3.2V

Parachute

Pressure


PWM

Flag



5V line


Other line

3.2V line

3.7V line

3.3V line


Structure


Actuator

Sensor



GPS

Relay switch

Nichrome wire

Battery 3.7V

5V Regulator

3.3V Regulator

Parafoil

Battery 3.2V

Parachute

Pressure


PWM

Flag



5V line


Other line

3.2V line

3.7V line

3.3V line



Actuator

Sensor


OBC(PIC16F877)EEPROM Servo Motor

(S3102)

GPS(CCA-552JZ)

Relay switch

Nichrome wire

Battery 3.7V

5V Regulator

3.3V Regulator

Parafoil

Battery 3.2V

Parachute

5V line


Other line

Pressure(PSM001/2KPG)

3.2V line

Battery 3.7V Communication

Receiver Transmitter

3.7V line

PWM

Flag

Step3:Sensor and Actuator Integration & TestAssemble sensor & actuator with other subsystem as a CanSat.

Integration is carried out taking into consideration the problem which may arise at the time of integration. ―Power consumption, layout, algorithm, operation sequence, interference.

Try as many ground test as possible in various settings to ensure normal operation of CanSat.

Test is carried out to ensure normal operation of CanSat.―Integrated testing(performance check as a CanSat), Environmental Testing(thermal, vibration, etc), Calibration, Operation Testing

Satellite or CanSat cannot always be experimented or confirmed under the circumstance that is similar to the real one.

Results of number of experiments and confirmation tests are connected in order to build a trustworthy system.


3

3.2

3.4

3.6

3.8

4

4.2

4.4

0 5000 10000 15000 20000 25000

Main Battery

Servo Battery

Waiting for launch

Servo system is ON(1hour)

Voltage

[V]

Time [sec]

Electric power verification Test


Launch!


Power ON



(Pressure & Nichrom wire)

Parafoildeployment


Landing

44 What should we consider? Control Algorithm & Ground test

East longitude [deg.]

North latitud

e [deg.]

Direction of movement

(GPS)Neutral

Right small turn

Right large turn Left large turn

Left small turn

Objective point

45 What should we consider? Parafoil performance test

Wind-tunnel test

Flight Test

46 What should we consider? Interference

GPS-MPU

GPSRadio shielding sheet

47 What should we consider? Interference

Communication-Sensor

-0.4

-0.2

0

0.2

0.4

0.6

0 200 400 600 800 1000 1200

BxByBz

Mag

netic

flux

den

sity

[gau

ss]

Time [sec]

CW started


48

Balloon experiment

OPEN

Reel

CanSat

Balloon

100～150m

Ground Station

49 What should we consider? Balloon experiment


North latitud

e [deg.]

50 What should we consider? Balloon experiment


North latitud

e [deg.]

Step1:Sensor and Actuator selectionWhat kind of sensors & actuator are available. How easy to implement―Spec(How accurate?, How often?), Environmental tolerance, Power

consumption, Data form(Digital/Analog), Size, Weight, Operatingvoltage… ）

Step2:Sensor and Actuator AssemblyStep3:Sensor and Actuator Integration & TestPower consumption, layout, algorithm, operation sequence, interference,Integrated testing(performance check as a CanSat), EnvironmentalTesting(thermal, vibration, etc), Calibration, Operation Testing

・Imagine the flight as completely as possible!

・It is important to consider the interference between sub-systems.

・Confirm the sequence of the mission, and check the validity of the sensordata and the actuator motion, the success of the communication, the powerconsumption of the batteries, and so on.

51 What should we consider? Operation mode control

Mode Control Example by Level detection IC

Low battery voltage → Operation controlHigh battery voltage → Shunt control

52 What should we consider? Antenna deployment mechanism

53 What should we consider? Sun sensor

For example, our SPROUT mounts 6 sun sensors

Sun sensorPinhole

Hood

Position Sensitive Detector

54 What should we consider? Sun sensor(using solar cell current)

55 What should we consider? Calibration

56 What should we consider? Manufacturing

Bearing

Bearing Torque rod

Coil wire

Slide rail

57 What should we consider? CanSat for CubeSat

Mission ObjectiveAssembly, integration & test of part of CubeSat(Sensor, Data communication, Data save)Mission sequence simulation of part of CubeSat

Summary

I think, The main task of sensor is to detect a satellite condition, e.g. battery

voltage, solar cell current, thermal and attitude, etc. The main task of actuator is to control a satellite condition, e.g. orbit

and attitude, deployment of solar panel and antenna, etc. Imagine the flight as completely as possible!

In this lecture, I talked about Role of sensor and actuator. Design example of satellite and CanSat sensor and actuator subsystem.

cltp4 sensor actuator pdf配布用 - uniseccltp4_sensor_actuator.pdf · use case of satellite...

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