A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... ·...
Transcript of A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... ·...
![Page 1: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/1.jpg)
Ankur Sarker*, Chenxi Qiu†, and Haiying Shen* *Dept. of Computer Science, University of Virginia, USA
† College of Information Science and Technology, Pennsylvania State University, USA
A Decentralized Network in Vehicle
Platoons for Collision Avoidance
![Page 2: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/2.jpg)
• Introduction
• System Design
• Interference avoidance
• The minimum number of channels
• Performance Evaluation
• Conclusions
Outline
2
![Page 3: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/3.jpg)
Introduction As a future form of road transportation system, vehicle platoon has great potential.
![Page 4: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/4.jpg)
Introduction In a platoon, one leader vehicle and several follower vehicles drive in a single lane, maintain a safety inter-vehicle distance.
. . .
![Page 5: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/5.jpg)
Introduction • Vehicle platoon provides-
– Higher traffic throughput
– Better traffic flow control
– Increase energy efficiency
• Inter-vehicle communication is crucial
– Avoid unwanted collisions between vehicles
– Strictly maintain safety distance
![Page 6: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/6.jpg)
Introduction Existing centralized approaches -
•Platoon wrt sensor failures (ITS ‘14)
•Model predictive controller (CTS ‘11)
•Platoon dynamic beaconing (INFOCOM’13)
However-
•Do not consider dynamic joining/leaving of vehicles
•Introduce single point of failure
•Limited number of vehicles
•Safety cannot be guaranteed
![Page 7: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/7.jpg)
Introduction Proposed decentralized approach-
•Vehicles have short range communication device
•Guarantee vehicles’ safety
•Increase the number of vehicles
•Dynamic formation of platoon
![Page 8: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/8.jpg)
Introduction How to reduce signal interference?
Multiple active transmissions is crucial for safety
![Page 9: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/9.jpg)
Introduction How to reduce signal interference?
Efficient channel allocation technique using platoon features.
Multiple active transmissions is crucial for safety
![Page 10: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/10.jpg)
Introduction
• Utilize platoon architecture
• Distribute channels based on interference range
• Allow minimum number of channels
Our proposed method: Fast and Light weight
Autonomous channel allocation technique
Advantages • Decide communication channel automatically • Reduce signal interference
![Page 11: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/11.jpg)
• Introduction
• System Design
• Interference avoidance
• The minimum number of channels
• Performance Evaluation
• Conclusions
Outline
11
![Page 12: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/12.jpg)
Vehicle channel allocation problem
12
Given: •A finite set of senders S and their respective receivers R in a geometric plane, decoding threshold γth, and a constant Λ.
Problem: •Using Λ channels, whether there exists a schedule, such that the SINR received by each vehicle receiver is higher than γth?
![Page 13: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/13.jpg)
Overview of Proposed Approach
13
Number of Channels: •Determine the minimum number of channels based on signal interference.
Autonomous channel selection: •Each vehicle selects the communication channel based on its segment ID in platoon
Goal: •Choose a channel allocation method so that communication overhead can be reduced
![Page 14: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/14.jpg)
The minimum number of channels
14
The required number of channels: •Based on the transmission range of vehicles (R), path loss exponent (α), decoding threshold γth, and segment distance δ •If the distance between two segments is kgδ •The safety distance between two segments is kgδ − δ •The interference generated from nearby vehicles is at most P(kgδ −δ)−α
![Page 15: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/15.jpg)
The minimum number of channels
15
The required number of channels:
•The sum interference received by each vehicle is at most P(g − 1)−αδ−αζ(α) •Then, the minimum number of channel, g, is equal to ⌈(Rαδ−αζ(α)γth)1/α+ 1⌉
[More details in the paper]
![Page 16: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/16.jpg)
The autonomous channel selection
16
![Page 17: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/17.jpg)
The autonomous channel selection
17
The channel selection:
•It associates each distance offset with each channel in g channels •A vehicle receives this table from its preceding vehicle after it joins the platoon. This table is kept in each vehicle’s storage •Since the partition is static over time, once the table is built, each vehicle does not need to change the FLA table anymore
![Page 18: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/18.jpg)
The autonomous channel selection
18
The channel selection:
•Using the FLA table, each vehicle only needs to know its distance from the leader vehicle •The leader vehicle’s current location is periodically propagated to all the follower vehicles • By piggybacking, leader’s location information is periodically sent from a preceding vehicle to its succeeding vehicle
![Page 19: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/19.jpg)
The autonomous channel selection
19
The channel selection:
•Based on the location, each follower vehicle can calculate its distance from the leader vehicle •Then, it checks the FLA table by the calculated distance offset and finds the corresponding channel
![Page 20: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/20.jpg)
The autonomous channel selection
20
The channel selection:
•For example, if the safety distance is 30m, the number of channels, g, is 5. If, a vehicle i estimates that the distance between the leader vehicle and itself is 195m •Then, vehicle i’s distance offset equals 195 mod (30 × 5) = 45m •Since 45 ∈ [30,60), it chooses channel 2 based on the FLA table
![Page 21: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/21.jpg)
• Introduction
• System Design
• Interference avoidance
• The minimum number of channels
• Performance Evaluation
• Conclusions
Outline
21
![Page 22: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/22.jpg)
Performance Evaluation: Settings
22
• Simulation
• Platoon Network • Network Simulator 3
• Channel allocation • Matlab
– 6-30 vehicles
[3] https://www.palmetto.clemson.edu/palmetto/.
• Comparison methods
– Centralized platoon network
– Graphed-based channel allocation
– SINR-based channel allocation
![Page 23: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/23.jpg)
Performance Evaluation: Results
23
• Average packet drop and delay wrt network
• Observation: Decentralized platoon network < Centralized platoon network
• Reason: In Decentralized platoon network, vehicles only communicate with neighbors.
Setting: different number of vehicles
![Page 24: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/24.jpg)
Performance Evaluation: Results
24
• Number of vehicles and safety violation wrt network
• Observation: Decentralized platoon network < Centralized platoon network
• Reason: In Centralized platoon network, the length of platoon limits the number of vehicles inside platoon. Also, Higher packet delay causes more safety violations.
Setting: different number of vehicles
![Page 25: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/25.jpg)
Performance Evaluation: Results
25
• Packet delivered ratio and delay wrt channel allocation methods
• Observation: FLA is better than Graph-based and SINR-based methods
• Reason: In FLA, each packet does not need to wait longer time for other packets.
Setting: different number of vehicles
![Page 26: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/26.jpg)
Performance Evaluation: Results
26
• Communication cost and safety violation wrt channel allocation methods
• Observation: FLA ≤ SINR-based ≤ Graph-based
• Reason: In FLA, vehicle can change its own channel based on its scored FLA table. Also, vehicle can adjust its position quickly in FLA to avoid collisions.
Setting: different number of vehicles
![Page 27: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/27.jpg)
• Introduction
• System Design
• Interference avoidance
• The minimum number of channels
• Performance Evaluation
• Conclusions
Outline
27
![Page 28: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/28.jpg)
Conclusion
28
• Fast and Light weight Autonomous channel allocation: allocates channel based on interference range
• Simulation in different scenarios evaluate:
• Reduce packet drop rate, packet delay, and communication cost
• Support more vehicles in platoon
• Reduce safety violation and provide more safety
• Future work: Study different channel allocation models for high-speed decentralized platoon network
![Page 29: A Decentralized Network in Vehicle Platoons for Collision Avoidancehs6ms/publishedPaper/... · 2016. 10. 21. · •Platoon dynamic beaconing INOOM í ï However- •Do not consider](https://reader035.fdocuments.us/reader035/viewer/2022071511/6130c3be1ecc515869444e30/html5/thumbnails/29.jpg)
Thank you!
Questions & Comments? Ankur Sarker
Department of Computer Science
University of Virginia
29