Study on Automatic Collision Avoidance System andnfas.autonomous-ship.org/events/icmass19/71_icmass19.pdf · 2019-12-16 · CONCEPT OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRING •

Study onAutomatic Collision Avoidance System

and Method for Evaluating Collision Avoidance Manoeuvring Results

Shinya Nakamura : Japan Marine Science Inc.Naoki Okada : Japan Marine Science Inc.Satoru Kuwahara : Japan Marine Science Inc.Koji Kutsuna : MTI Co., Ltd.Takuya Nakashima : Mitsubishi Research Institute, Inc.Hideyuki Ando : MTI Co., Ltd.

MTEC / ICMASS 2019

INTRODUCTION

• Development of an automatic collision avoidance system for unmanned Autonomous ships(Remote maneuvering)

• Development of evaluation method of automatic collision avoidance maneuvering results

Goals of Study

2

CONCEPT OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRING

•Ship manoeuvring which minimizes the economic loss, constantly selects a low-risk course from an early stage and reduces the encounter situation where the manoeuvring load is high

Strategic Collision Avoidance Manoeuvring

3


• There are many ambiguous expressions in the current COLREGs (ex Action by stand-on vessel, she shall take such action as will best aid to avoid collision)

• Therefore, the desirable automatic system takes action to reduce the risk before the “Conduct of Vessels In Sight of Another" defined by the COLREGs is applied.

• It should be avoided that the rules of “Action by stand-on vessel” apply


4

Conduct of vessels in sight of one another

Rule 17 Action by stand-on vessel

………… The vessel required to keep her course and speed finds herself so close that collision cannot be avoided by the action of the give-way vessel alone, she shall take such action as will best aid to avoid collision


• Developed an automatic collision avoidance system considering the realization of strategic collision avoidance manoeuvring

A method of altering her course or changing her speed to reduce the risk before rules defined by CORLEGs is applied


5

Collision Risk

Highest Ev(Xij)Altering course 24deg. at the Present Speed

𝐸𝐸𝐸𝐸 𝑋𝑋𝑖𝑖,𝑗𝑗 = 𝑃𝑃𝑃𝑃 𝑋𝑋𝑖𝑖,𝑗𝑗 − 𝛼𝛼 � max 𝑅𝑅 𝑋𝑋𝑖𝑖,𝑗𝑗

Clossing situationTarget ShipLoa 175m, 12kts

Own ShipLoa 175m, 12kts

Altering Co. Port 60deg. to Stb’d 60 deg. (i)

Preference of Manoeuvre(Minimizes the economic loss)

Risk

Lev

el

Pref

eren

ce L

evel

CONCEPT OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRINGPr

efer

ence

Lev

el

6

How to calculate the collision risk by using exclusive area

𝑅𝑅 𝑋𝑋𝑖𝑖,𝑗𝑗 = 𝑀𝑀𝑀𝑀𝑀𝑀 𝑅𝑅𝑥𝑥 ,𝑅𝑅𝑦𝑦 � 1 −𝑇𝑇𝑇𝑇𝑇𝑇𝑀𝑀𝑊𝑊𝑊𝑊𝑇𝑇𝑇𝑇𝑀𝑀

a

c

bd

Distance

Direction ofRelative Movement

Vt

Own ShipVo

Vt

VR

Relative y -axis

Relative x -axis

Absolute Y-axis

Ry k

Rx k

1.0

1.0Target Ship

Function indicating collision risk

Yt

Xo

Yo

Xt Absolute X -axis

Function indicating collision risk

Ry

Rx

Own Ship

Target Ship


Collision Risk:Select larger one of Rx and Ry

7

×20×2


8

EVALUATION METHOD OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRING RESULTS

Towards level certification of automatic collision avoidance system

9

•The desirable automatic collision avoidance system should reduce the risk before rules defined by CORLEGs is applied

Therefore ………..

EVALUATION METHOD OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRING RESULTS

Towards level certification of automatic collision avoidance system

Evaluation by“Relative distance" and “Bearing change rate“

Three areas are defined according to the encounter situation with other ships

It was formulated in an experiment in which 12 captains and pilots participatedTotal Number of data reached approx. 30,000 points

10

Unacceptable areaThe area where own ship commence to avoid or expect another ship to avoidAcceptable area

“Danger area”“Caution area”“Safety area”

Safety area → It means collision avoidance manoeuvring that dose not give anxiety to the target ship

Automatic collision avoidance manoeuvringthat dose not give anxiety to the target ship

2.3 miles 2.3 miles

View fromOwn Ship

View fromTarget Ship

Time

0:00

Bow

Cro

ssin

g

Di s t. [Miles]

[Head-on / Crossing Situation]

Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

11

Not give anxiety Give anxiety

2.1 miles 2.1 miles

Time

0:30

Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

View fromOwn Ship



12


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.9 miles 1.9 miles

Time

1:00


View fromOwn Ship


13


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.8 miles 1.8 miles

Time

1:30

View fromOwn Ship



14


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.6 miles 1.6 miles

Time

2:00


View fromOwn Ship


15


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.5 miles 1.3 miles

Time

2:30


View fromOwn Ship


16


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.2 miles 1.1 miles

Time

3:00


View fromOwn Ship


17


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

1.1 miles 1.0 miles

Time

3:30


View fromOwn Ship


18


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

0.9 miles 0.8 miles

Time

4:00


View fromOwn Ship


19


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

0.8 miles 0.6 miles

Time

4:30


View fromOwn Ship


20


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

0.6 miles 0.5 miles

Time

5:00


View fromOwn Ship


21


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

0.4 miles0.5 miles

It is a situation still shows own ship starboard side to the other target ship at the distance is 0.4mile. It can be said that it isa situation giving anxiety

Time

5:30


View fromOwn Ship


Bow Crossing 0.4 miles

22

Not give anxiety

0.3 miles

Time

6:00


View fromOwn Ship


Bow

Cro

ssin

g

Di s t. [Miles]


Danger Caution

Safety Safety

CautionDanger


Dist. [Miles]

Bow

Cro

ssin

g

though collision can be avoided …….

Manoeuvringthat Dose Not Give Anxiety to the Target Ship

Manoeuvringthat Dose Give Anxiety to the Target Ship

Deduction Point：0 Deduction Point：-75.3

23


Weighting coefficient ➡ Danger：-2, Caution：-1 Calculated based on the ratio of time in the area

Deduction Point 0 → It means desirable collision avoidance manoeuvring that dose not give anxiety to the target ship.

This evaluation area chart is effective for safety evaluation of automatic collision avoidance systems.

Comparison of Manoeuvring Results by Automatic Collision Avoidance System and Manoeuvring Result by Human

Verification experiments using a full mission simulator Comparison of the maneuvering results of "Automatic Collision avoidance system""Veteran captain“ and "Inexperienced Officer"

24

Experimental Scenario in Actual Congested Sea Area

0 20NM

Head-on Vessels,Same way Vessels

<056>

<020>

<003>

Own ShipPlaned Route

For Osaka, Kobe


25


26

計画針路Planed Route

Veteran CaptainPerforming a large course change to clearly show the intention

Inexperienced OfficerJudgment of avoidance is slightly delayed and enters caution area, and deviation from planned course is large

Automatic SystemWhile ensuring a sufficient heading change that does not give anxiety to other ships, it seeks an optimal solution, so there is a slight deviation from the planned course compared to a veteran captain


Comparison by own ship’s track chart

27

Relative distance and bearing change rate of all encounter vesselsAutomatic System

Deduction Point： 0Veteran Captain

Deduction Point： 0Inexperienced OfficerDeduction Point： -5.7


Danger Danger Danger

Caution Caution Caution

Safety Safety Safety

Safety Safety Safety

Caution Caution Caution

Dist [Miles] Dist [Miles] Dist [Miles]

Bow Crossing Bow Crossing Bow Crossing

Stern Crossing Stern Crossing Stern Crossing

Bear

ing

chan

ging

rate

[deg

/min

]

Bear

ing

chan

ging

rate

[deg

/min

]

Bear

ing

chan

ging

rate

[deg

/min

]


There was no deduction point in manoeuvring of the automatic system and the veteran captain.

28

Relative distance and bearing change rate of all encounter vessels



【Crossing from Port 】【Crossing from Port 】

【Head-on / Crossing from Starboard 】【Head-on / Crossing from Starboard 】

Baw

Cro

ssin

g

Baw

Cro

ssin

g

Baw

Cro

ssin

g

Baw

Cro

ssin

g

Ster

n Cr

ossin

g

Ster

n Cr

ossin

g

Ster

n Cr

ossin

g

Ster

n Cr

ossin

g

Danger Danger

Caution Caution

Caution Caution

The system dose not calculate only immediate danger. Therefore the automatic system is better at preventing “lack of situational awareness”

29

Automatic SystemDeduction Point： -1.4

Veteran CaptainDeduction Point： -15.4

Cement carrierGT: Deadweight tons:LOA:Lpp:Draft:Speed:

“Kouzan Maru”14,902t22,053t160.9m153.7m8.9m13.0kt

Verification Experiment on Actual Ship

TOKYOLT: 2019.Jan.18 JST1530h

UBEAT:2019.Jan.20 JST1100h

Number of AIS Ships：5,911Ships

30

Off the Coast of Yokohama Immediately after leaving Tokyo

Preference Course : Stb’d 10 deg.Preference order

Risk

Own ShipCrossing Ships

Same-way Ship

Preference CourseCaution

Caut

ion

Bow

Cro

ssin

gSt

ern

Cro

ssin

gBe

arin

g Ch

angi

ng ra

te [d

eg./m

in.]

[Head-on / Crossing Situation] [Same-way Si tuation]

Dist. [Miles] Dist. [Miles]

Danger Caution

Alter Course → Stb’d 10deg.

Relative Track ChartTrack Chart

Own Ship Own Ship

Crossing Ships

Crossing Ships

Same-way ShipSame-way Ship

Yokohama

Alter Course to Stb’d 10 deg.

2 1 0 1 Dist. [Miles] 8 6 4 2 0 Dist. [Miles]

2

1

0

1

D

ist.

[Mile

s]

6

4

2

0

D

ist.

[Mile

s]


Crossing ships from Stb’d side are encountered with the Manouevring area being restricted by same-way ships

Yokohama

Risk

Preference Order

31

Congested Water around Japan Coast

Own Ship

Own Ship

Head-on Ships

Head-on Ships

2 1 0 1 Dist. [Miles]

2

1

0

1

D

ist.

[Mile

s]

8 6 4 2 0 Dist. [Miles]

Alter Course to Stb’d 8 deg.

Track Chart Relative Track Chart

8

6

4

2

0

D

ist.

[Mile

s]

DangerCaution

Caution

Caut

ion

[Head-on / Crossing Situation] [Same-way Situation]

Bow

Cro

ssin

gSt

ern

Cro

ssin

gBe

arin

g Ch

angi

ng ra

te [d

eg./m

in.]

Dist. [Miles] Dist. [Miles]

Alter Course → Stb’d 8 deg.

Own ShipRisk

Preference orderPreference Course : Stb’d 8 deg.

Head-on Ships

Preference Course


In the Situation of Encounter with Head-on Ships

32

Conducted the world’s first Maritime Autonomous Surface Ships (MASS) trial performed in accordance with the IMO’s Interim Guidelines for MASS

“IRIS LEADER”, a large NYK-operated PCTC having a gross tonnage of 70,826 tons, was navigated day and night using the Automatic Collision Avoidance System during the period from 14 to 19 September 2019 from Xinsha, China, to the port of Yokohama, Japan. (https://www.nyk.com/english/news/2019/20190930_01.html)


33

Target Data: AIS + Radar TT

Conclusion

In order to carry out strategic collision avoidance manoeuvring, an automatic collision avoidance system constantly calculating optimal manoeuvring method was introduced.

A system that evaluates the situation that entered "Danger area" and "Caution area" using the relative distance and bearing change rate with a deduction-based evaluation system was proposed.

Validity verification of the developed automatic collision avoidance system was carried out compared to the manoeuvring results of veteran captain and officers.It was verified that the collision avoidance manoeuvring by the automatic collision avoidance system is almost equal to that by veteran captain.

Verification experiments were successfully conducted to verify the effectiveness of the proposed automatic collision avoidance system on the actual ship navigating in congested waters..

34

35

Case 01 Case 02 Case 03 Case 04


～～14NM

Loa: 175m16.1 kts < 180>DCPA : 0.0NMT CPA : 26.1min

Loa: 200m16.1 kts < 000>

～～14NM


Loa: 200m16.1 kts < 000>

300m

～～14NM


Loa: 200m16.1 kts < 000>

300m

6NM

Loa: 175m5.0 kts < 000>

DCPA : 0.0NMT CPA : 29.8min

Loa: 200m16.1 kts < 000>

Head-on Head-on Head-on Overtake

3NM


Loa: 200m16.1 kts < 000>

3NM

3NM


Loa: 200m16.1 kts < 000>

3NM

～～10NM


Loa: 200m16.1 kts < 000>

10NM～～

10NM


Loa: 200m16.1 kts < 000>

10NM

～～

～～

Cross Cross Cross Cross

2



3NM


Loa: 200m16.1 kts < 000>

3NM30°

3NM


Loa: 200m16.1 kts < 000>

3NM 30°

～～10NM


Loa: 200m16.1 kts < 000>

10NM 30°

10NM


Loa: 200m16.1 kts < 000>

10NM30°

～～


～～10NM


Loa: 200m16.1 kts < 000>

10NM

40°10NM


Loa: 200m16.1 kts < 000>

10NM40°

～～


3

～～10NM


Loa: 200m16.1 kts < 000>

10NM 30°

10NM


Loa: 200m16.1 kts < 000>

10NM30°

～～


Case 21 Case 22 Case 23

～～10NM


Loa: 200m16.1 kts < 000>

10NM20°10NM


Loa: 200m16.1 kts < 000>

10NM 20°～～

Same WaySame Way

～～12NM


Loa: 200m16.1 kts < 000>

300m


7NM～～

Same WayCrossHead-on

～～12NM


Loa: 200m16.1 kts < 000>

300m


7NM～～

1,200m

300m

Loa: 175m18.0 kts < 000>DCPA : 0.6NMT CPA : -

12NM

Loa: 175m16.1 kts <180>

Own ShipLoa: 200m16.1 kts <000>

300m

Loa: 150m16.1 kts <270>

7NM

1,200m

300m

Loa: 150m16.1 kts <270>

Loa: 150m16.1 kts <270>

Loa: 150m16.1 kts <090>

Loa: 150m16.1 kts <106>

7NM

Loa: 175m18.0 kts <000>

Same WaySame Way

Same WayCrossHead-onCrossHead-on

4

～～10NM


Loa: 200m16.1 kts < 000>

10NM20°10NM


Loa: 200m16.1 kts < 000>

10NM 20°～～

15°0.00' N

15°10.00' N

129°40.00' E 129°50.00' E 130°0.00' E 130°10.00' EN

0 10NM

0 20000m

5

Bungo-Suidou

Planed Route

33°50.00' N

34°0.00' N

34°10.00' N

134°30.00' E 134°40.00' E 134°50.00' E 135°0.00' E 135°10.00' EN

0 10NM

0 20000m

Kii-Suidou

Planed Route

①② ④

③

⑤

⑥

⑦

36

Same WayCrossHead-on

12NM

Loa: 175m16.1 kts <180>

Own ShipLoa: 200m16.1 kts <000>

300m

Loa: 150m16.1 kts <270>

7NM

1,200m

300m

Loa: 150m16.1 kts <270>

Loa: 150m16.1 kts <270>

Loa: 150m16.1 kts <090>

Loa: 150m16.1 kts <106>

7NM

Loa: 175m18.0 kts <000>

SHIP: IRISLEADER[Loa=200 .0m, B=34 .8m]

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32Time[min]

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

OG[kts]

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32Time[min]

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

Rudder(S)[deg]

OG Speed [kts]

Rudder [deg.]

②

① ④

③

⑤

⑥

⑦

15°0.00' N

15°10.00' N

0 5NM

0 10000m 0 min 16.1 kts <000>

3 min 12.5 kts <008>

6 min 12.7 kts <011>

9 min 13.7 kts <010>

12 min 15.1 kts <011>

15 min 15.2 kts <010>

18 min 15.2 kts <012>

21 min 16.2 kts <002>

24 min 12.6 kts <357>

27 min 11.1 kts <358>

30 min 11.0 kts <359>

33 min 11.0 kts <358>

37

相対航跡図評価領域図

② ②①①

③

④

⑤

⑤

⑥

⑦

⑦

⑥

④

Own Ship

⑦

38

Documents

Study on Automatic Collision Avoidance System andnfas.autonomous-ship.org/events/icmass19/71_icmass19.pdf · 2019-12-16 · CONCEPT OF AUTOMATIC COLLISION AVOIDANCE MANOEUVRING •