Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
PhD Defense | July 1, 2025
Abenezer Girma Taye
Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
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Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
Fatalities
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Challenges with the current ground-based transportation
In 2023, 40,990 people lost their lives in motor vehicle crashes in the United States [1]
[1] National Highway Traffic Safety Administration.
Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
Fatalities
Traffic Congestion
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Challenges with the current ground-based transportation
In 2024, average U.S. driver lost 43 hours to traffic congestion [2]
[2] INRIX Global Traffic Scorecard
Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
Fatalities
Traffic Congestion
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Challenges with the current ground-based transportation
The largest contributor to U.S. greenhouse gas emissions 29% [3]
[3] U.S. Environmental Protection Agency
Emission
Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
Fatalities
Traffic Congestion
Expensive
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Challenges with the current ground-based transportation
The second-largest expense in a typical American household [4]
[4] Bureau of Transportation Statistics
Emission
Enhancing Safety and Energy-Efficiency in Advanced Air Mobility Through Trajectory Planning and Mission Feasibility Assessment Strategies
Fatalities
Traffic Congestion
Expensive
Stressful
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Challenges with the current ground-based transportation
Higher risk of depression and anxiety - elevate cardiovascular health risks [5]
[5] Yuliya Y Shitova. The impact of long-distance travel to work on the health of commuting labour migrants: a literature review. Population and Economics, 2024.
Emission
Advance Air Mobility (AAM)
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Image credit – airdatanews, Getty/PhonlamaiPhoto, Unmanned Airspace
What is AAM? “An emerging sector in the aerospace industry that aims to safely and efficiently integrate highly automated aircraft into the national airspace system (NAS)” |
[6] https://www.faa.gov/air_traffic/publications/atpubs/aim_html/chap11_section_6.html
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[7] Video credit: https://www.jobyaviation.com/
AAM Challenges
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[8] George Price, Douglas Helton, Kyle Jenkins, Mike Kvicala, Steve Parker, Russell Wolfe, Felix A Miranda, Kenneth H Goodrich, Min Xue, Karen Tung Cate, et al. Urban air mobility operational concept (opscon) passenger-carrying operations. 2020.
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AAM Challenges
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Safe and Scalable Real-Time Trajectory Planner for UAM Operations
Chapter 2
Energy-Efficient Trajectory Planning and Mission Feasibility Assessment Framework
Chapter 3
Online Mission Feasibility Assessment and Contingency Management Framework
Chapter 4
[8] George Price, Douglas Helton, Kyle Jenkins, Mike Kvicala, Steve Parker, Russell Wolfe, Felix A Miranda, Kenneth H Goodrich, Min Xue, Karen Tung Cate, et al. Urban air mobility operational concept (opscon) passenger-carrying operations. 2020.
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AAM Challenges
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Online Mission Feasibility Assessment and Contingency Management Framework
Chapter 4
Energy-Efficient Trajectory Planning and Mission Feasibility Assessment Framework
Chapter 3
Safe and Scalable Real-Time Trajectory Planner for UAM Operations
Chapter 2
LLM-based Flight Planning
[DASC, 2024]
Energy-Aware Traffic Management
[SciTech, 2025]
eVTOL Charging Infrastructure Planning
[Aviation, 2024]
Computer Vision based
Autonomous Landing
[Aviation, 2025]
[8] George Price, Douglas Helton, Kyle Jenkins, Mike Kvicala, Steve Parker, Russell Wolfe, Felix A Miranda, Kenneth H Goodrich, Min Xue, Karen Tung Cate, et al. Urban air mobility operational concept (opscon) passenger-carrying operations. 2020.
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Problem Statement Summary
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Develop trajectory planning and mission feasibility assessment strategies to
enable safe, scalable, energy-efficient, and resilient operations in AAM.
Overarching Research Objective
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Problem Statement Summary
14
Develop trajectory planning and mission feasibility assessment strategies to
enable safe, scalable, energy-efficient, and resilient operations in AAM.
Overarching Research Objective
How can we generate energy-efficient trajectories and assess mission feasibility?
How can we assess the feasibility of a flight mission online and manage a contingency?
How can we ensure both safety and scalability
in UAM trajectory planning?
Chapter 2
Chapter 3
Chapter 4
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Safe and Scalable Trajectory Planner for
Urban Air Mobility Operations
[9]Abenezer G. Taye, Josh Bertram, Chuchu Fan, and Peng Wei. “Reachability-based online safety verification for high-density urban air mobility trajectory planning,” AIAA AVIATION 2022 Forum, 2022.
[10]Abenezer G. Taye, Roberto Valenti, Akshay Rajhans, Anastasia Mavrommati, Pieter J. Mosterman, and Peng Wei. “Safe and scalable real-time trajectory planning framework for urban air mobility,” Journal of Aerospace Information Systems (JAIS), 2024.
Motivation: Urban air mobility
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|
[10] Urban Air Mobility (UAM) Concept of Operations (ConOps) Version 2.0. 2020
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Motivation
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Urban air mobility (UAM) is -
Multi-Agent System
Safety-Critical
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Motivation
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Safety is the first design requirement
Multi-Agent System
Safety-Critical
Scalability is the second design requirement
General Idea
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Motivation
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Safety is the first design requirement
Multi-Agent System
Safety-Critical
Scalability is the second design requirement
General Idea
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Contributions
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Safe and scalable UAM
trajectory planner
Action shielding mechanism
to enhance safety
Reward shaping mechanism
to enhance safety
State
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Problem Formulation
Ownship
Intruder
Intruder
Unsafe
Area
Unsafe
Area
Free-flight based urban air mobility operation
Goal
Vertiport
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Problem Formulation
Ownship
Intruder
Intruder
Unsafe
Area
Unsafe
Area
Assumptions
Vertiport
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Problem Formulation
Ownship
Intruder
Unsafe
Area
Markov Decision Process
Reachability Analysis
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MDP Formulation
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Formulation: Markov decision process based safe and scalable trajectory planner |
Urban Air Mobility Scenario
Reward Function
V
Unsafe
area
Unsafe
area
Ownship
Vertiport
Guidance Model [4]
[11] Beard, R. W., and McLain, T. W., Small unmanned aircraft: Theory and practice, Princeton University Press, 2012
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MDP Formulation
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State transition
Formulation: Markov decision process based safe and scalable trajectory planner |
Action set
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Reachability Analysis
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Formulation: A reachable set of a system refers to a set that contains all possible future states of the system Data-driven reachability analysis tool known as DryVR [12] |
Compute discrepancy parameters
Compute sensitivity parameters
Compute distance between trajectories
[12] Fan, C., Qi, B., Mitra, S., and Viswanathan, M., “DryVR: Data-Driven Verification and Compositional Reasoning for Automotive Systems,” Computer Aided Verification, edited by R. Majumdar and V. Kunčak, Springer International Publishing, Cham, 2017
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Reachability Analysis
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Working Procedure
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Compute rewards
Future states
Value
function
Update
states
Best
actions
Goal reached?
Remove aircraft
Aircraft 1
Assign initial and goal states
Update
states
Best
actions
Value
function
Compute rewards
Future states
Goal reached?
Remove aircraft
Aircraft 2
Assign initial and goal states
Update
states
Goal reached?
Best
actions
Value
function
Compute rewards
Future states
Remove aircraft
Aircraft N
Assign initial and goal states
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Simulation Results
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Aircraft
Future 10 sec trajectory
Goal state
Traveled path
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Simulation Result for 8 Agents
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Simulation Result for 16 Agents
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Simulation Result for 32 Agents
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Results
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Experimental Settings: 25 Experiments for each case Near Mid Air Collision (NMAC) 🡪 152m horizontal and 30m vertical separation [6] All experiments are conducted on Intel(R) Xeon(R) W-2133 cores running at 3.60GHz |
[13] S. Chen, A. Evans, M. Brittain and P. Wei, “Integrated Conflict Management for UAM with Strategic Demand Capacity Balancing and Learning-based Tactical Deconfliction”, IEEE Transactions on Intelligent Transportation Systems, vol. 25, no. 8, Jan. 2024.
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Action Shielding
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Objective: Filter out actions that result in unsafe states [14] |
Future States
Shield
Dead-lock Control Actions
[14] K.nighofer, B., Lorber, F., Jansen, N., and Bloem, R., “Shield synthesis for reinforcement learning,” Leveraging Applications of
Formal Methods, Verification and Validation: Verification Principles. ISoLA 2020, Rhodes, Greece, Springer, 2020
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Reward Shaping
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State
Objective: Modify the reward received by the agent to guide the agent toward desired behaviour [15] |
Modified
Reward
Reward Shaping
Function
Difference of
Potentials
[15] Ng, A. Y., Harada, D., and Russell, S., “Policy invariance under reward transformations: Theory and application to reward
shaping,” International Conference on Machine Learning (ICML), Vol. 99, 1999
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Energy-Efficient Trajectory Planning and Mission Feasibility Assessment Framework
[16] Abenezer Taye, Ellis L. Thompson, Peng Wei, Timothy Bonin, and James C. Jones. “Probabilistic evaluation for flight mission feasibility of a small octocopter in the presence of wind,” AIAA AVIATION 2023 Forum.
[17] Abenezer G. Taye and Peng Wei. “Flight mission feasibility assessment of urban air mobility operations under battery energy constraint,” AIAA SCITECH 2024 Forum.
[18] Abenezer G. Taye and Peng Wei. “Energy-efficient trajectory planning and feasibility assessment framework for drone package delivery,” Journal of Aerospace Information Systems (JAIS), 2025.
Motivation: Drone package delivery
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Problem: Enhance safety and energy-efficiency of drone package delivery operations |
Zipline [1]
DroneUp [2]
Amazon Prime Air [3]
Wing [4]
UPS Flight Forward [5]
NASA [6]
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Motivation: Drone package delivery
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|
[19] Unmanned Aircraft System (UAS) Traffic Management (UTM) Concept of Operations (ConOps) Version 2.0. 2020
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Motivation: Drone package delivery
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Objective: Develop energy-efficient trajectory planner + feasibility assessment framework |
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Objective
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Problem Formulation
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Safe and energy-efficient trajectories
Our problem has two major challenges
Mission feasibility assessment
Pre-departure flight planning and battery energy related flight mission feasibility assessment
Cleared for flight
Hold
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Contributions
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Energy-efficient trajectories
Mission feasibility assessment
Flight test validation
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Hierarchical Framework
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Working procedure of the proposed framework
Multi-Agent Trajectory
Planning
Mission Feasibility Assessment
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Upper Layer
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Trajectory Planner: Markov decision process based safe and energy-efficient trajectory planner |
Reward Function
Energy-Efficiency
Reachability Analysis
Package Delivery Scenario
Guidance Model [9]
[20] Corbetta, M., Banerjee, P., Okolo, W., Gorospe, G., and Luchinsky, D. G., “Real-time uav trajectory prediction for safety monitoring in low-altitude airspace,” AIAA AVIATION 2019 forum, 2019
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Upper Layer
Energy-Efficiency: A set of energy-efficiency reward functions have been developed |
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Energy Cost Function
Objective: Train an energy cost function |
Data collection
Future states
Battery simulation
Energy consumption
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Trajectory Deviation Reward
Objective: Compute the angle between each future state and the shortest path |
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Wind-Aware Planning
Objective: Compute the angle between velocity at each future state and wind field. |
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Results
Package Delivery Scenario: Collected CFD simulated wind data for a region near the city of Boston [10] |
[21] Baskar, D., and Gorodetsky, A., “A Simulated Wind-field Dataset for Testing Energy Efficient Path-Planning Algorithms for
UAVs in Urban Environment,” AIAA AVIATION 2020 FORUM, 2020
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Results
Package Delivery Scenario: Two aircraft conducting a package delivery mission from a depot |
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Results
Power Profile Comparison: Two aircraft conducting a package delivery mission from a depot |
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Lower Layer
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[22] Daigle, M., and Kulkarni, C. S., “Electrochemistry-based battery modeling for prognostics,” Annual Conference of the PHM Society, Vol. 5, 2013
Objective: Performs battery feasibility assessments for the generated trajectories |
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Lower Layer
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Objective: Performs battery feasibility assessments for the generated trajectories |
Electro-chemical-based model adopted from [12]
A detailed octocopter dynamics adopted from [11]
[23] Ahmed, I., Quinones-Grueiro, M., and Biswas, G., “A high-fidelity simulation test-bed for fault-tolerant octo-rotor control using reinforcement learning,” 2022 IEEE/AIAA 41st Digital Avionics Systems Conference (DASC), IEEE, 2022
[24] Daigle, M., and Kulkarni, C. S., “Electrochemistry-based battery modeling for prognostics,” Annual Conference of the PHM Society, Vol. 5, 2013
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Final Decisions
Flight Operator
Framework Workflow
Aircraft Type
Flight Planning and Feasibility Assessment
Framework
Battery SoC
Cleared for Flight
Hold the Aircraft
Keep Charging the Aircraft
Wind Forecast
Delivery
Locations
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Decision Making
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Objective: Performs battery feasibility assessments and make decisions based of the assessment |
Cleared for flight
Hold
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Decision Making
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Objective: Performs battery feasibility assessments and make decisions based of the assessment |
Cleared for flight
Hold
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Validation
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Objective: Hardware validation of the feasibility assessment framework |
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Validation
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Objective: Hardware validation of the feasibility assessment framework |
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Real-Time Flight Mission Feasibility Assessment and Contingency Management Framework
[*] The content of this chapter has been submitted to the 36th International Conference on Principles of Diagnosis and Resilient Systems (DX 2025) and is currently under review.
Problem Setting
Mission Feasibility
Depot Location
Delivery Location
Delivery Drone
Energy Consumption Model
Future
Trajectory
Learning based
Battery State Predictor
Battery state at
End of Flight
Research Problems
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Related Works
Energy Consumption Model
Future
Trajectory
Learning based
Battery State Predictor
Battery state at
End of Flight
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Proposed Framework
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Convert Power Profile
To Current Profile
Learning-based
Battery Model
Battery State Prediction
Initial and Final
Locations
Flight Plan
Generator
Identify Flight
Segments
Power
Consumption
Model
Power Consumption Prediction
Perform Feasibility
Assessment
Proceed?
Reroute
Feasibility Assessment and Decision Making
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Initial and Final
Locations
Flight Plan
Generator
Identify Flight
Segments
Power
Consumption
Model
Power Consumption Prediction
Power and Current Profile Prediction
Power Consumption Model
[25] Gina Sierra, M Orchard, Kai Goebel, and C Kulkarni. Battery health management for small-size rotary-wing electric unmanned aerial vehicles: An efficient approach for constrained computing platforms. Reliability Engineering & System Safety, 2019.
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Initial and Final
Locations
Flight Plan
Generator
Identify Flight
Segments
Power
Consumption
Model
Power Consumption Prediction
Power and Current Profile Prediction
Power Consumption Model
Power-to-Current Conversion
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Proposed Framework
65
Convert Power Profile
To Current Profile
Learning-based
Battery Model
Battery State Prediction
Initial and Final
Locations
Flight Plan
Generator
Identify Flight
Segments
Power
Consumption
Model
Power Consumption Prediction
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Proposed Framework
66
Convert Power Profile
To Current Profile
Learning-based
Battery Model
Battery State Prediction
Batteries
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Proposed Framework
67
Convert Power Profile
To Current Profile
Learning-based
Battery Model
Battery State Prediction
Batteries
Dataset Construction
Model Training & Evaluation
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Dataset Generation
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Full Flight and Mid-Flight Current Profiles
Simulated Voltage Trajectories
[26] Daigle, M., and Kulkarni, C. S., “Electrochemistry-based battery modeling for prognostics,” Annual Conference of the PHM Society, Vol. 5, 2013
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Neural Differential Equations (Neural ODEs)
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General Idea
|
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Physics Informed Neural Network (PINN)
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General Idea
|
Equivalent Circuit Model
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Results
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Package Delivery Scenario: Developed a drone package scenario in the Dallas Fort Worth area |
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Results
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Results
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Package Delivery Scenario: Developed a drone package scenario in the Dallas Fort Worth area |
Infeasible
Short
EM3
EM1
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Results
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Cleared for flight
Re-route
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Results
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Cleared for flight
Re-route
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Results
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Package Delivery Scenario: Spatial visualization of voltage predictions along each flight trajectory |
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Results
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Summary
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Develop trajectory planning and mission feasibility assessment strategies to
enable safe, scalable, energy-efficient, and resilient operations in AAM.
Overarching Research Objective
Energy-efficient trajectory planning and feasibility assessment framework
Real-time feasibility assessment and contingency management framework
Safe and scalable UAM trajectory planner
Chapter 2
Chapter 3
Chapter 4
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Future Works
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Energy-efficient trajectory planning and feasibility assessment framework
Real-time feasibility assessment and contingency management framework
Safe and scalable UAM trajectory planner
Chapter 2
Chapter 3
Chapter 4
deployment
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Publications
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Dissertation Related
Non-Dissertation
Open-Source Code
Chapter 2
Chapter 3
Chapter 4
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Thank You!�Questions and Comments
Abenezer Taye
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Other Experiences
Community Service
Summer Internships
Teaching
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Results
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Package Delivery Scenario: Developed a drone package scenario in the Dallas Fort Worth area |
Infeasible
Short
EM3
EM1
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Physics Informed Neural Network (PINN)
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General Idea
|
Equivalent Circuit Model
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Physics Informed Neural Network (PINN)
85
General Idea
|
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Physics Informed Neural Network (PINN)
86
General Idea
|
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Physics Informed Neural Network (PINN)
87
General Idea
|
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Physics Informed Neural Network (PINN)
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General Idea
|
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Neural Differential Equations (Neural ODEs)
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General Idea
|
State
Encoder
Decoder
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Neural Differential Equations (Neural ODEs)
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General Idea
|
① Deterministic
Latent space = Voltage space
② Voltage prediction
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Neural Differential Equations (Neural ODEs)
91
General Idea
|
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