Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades

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Presentation transcript:

Towards Online Electric Vehicle Scheduling for Mobility-On-Demand Schemes Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades EUMAS 2018

TOC Introduction Problem Domain Scheduling Algorithms: Short Mode, Long Mode MoD Software Package: Web Platform, Mobile App Testing and Evaluation Summary Let’s get started!

1-1. Introduction Current personal transportation model is based on ICE vehicles They cause high air and sound pollution They are accountable for 74% of global CO₂ emissions They suffer from low utilization rates of 30-35% EVs powered by electricity from renewable sources No tailpipe pollutants emitted High utilization rate of more than 90% Important role towards sustainable transportation Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

1-2. Introduction Mobility-on-Demand (MoD) systems One-way, vehicles can be picked up or dropped off at any of the stations Two-way, vehicles have to be dropped off at their initial station Free-floating, there are no stations, the customer can use any public parking The vision of Future Smart Cities MoD systems Using fleets of EVs Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

1-3. Introduction Challenges of EVs Limited range, they need to be charged regularly Sparse charging infrastructure, "chicken and egg problem" EVs are still more expensive than ICE vehicles How to incorporate EVs into MoD systems? Charging capacity should be managed and scheduled The maximum number of requests should be serviced Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

2-1. Problem Domain The MoD system Follows the one-way scheme Has preconfigured stations in a geographic area When a request is received, a scheduling algorithm is applied A suitable vehicle is assigned to the trip request The Agents (customers) Announce their intention to travel between two stations Choose the start time of the trip Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

2-2. Problem Domain The scheduling algorithm Accepts the customer requests for trips Decides on whether to accept or deny the requests Based on vehicles locations and their charge level Based on all already scheduled trips data For accepted requests, it schedules a vehicle for a trip How can the algorithm ensure that The maximum number of customers will be serviced? Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

2-3. Problem Domain The implementation How to store and manage all the data? How to calculate travel times and energy cost between locations? How to properly calculate and schedule vehicle trips? How to implement a software package with the algorithm? The simulation and test How to generate requests and perform testing? How to evaluate the test results? Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-1. Scheduling Algorithm: Short Mode Start station: Station A Step 1: Receive trip requests from customers Finish station: Station B 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-2. Scheduling Algorithm: Short Mode Start station: Station A Step 2: Calculate trip duration and energy cost based on station coordinates Finish station: Station B Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-3. Scheduling Algorithm: Short Mode Start station: Station A - Vehicles: EV1(86%, 10:15), EV2(5%, 10:20), EV3(22%, 10:35) Step 3: Get available vehicles in Station A, before start time, without future routes Finish station: Station B Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-4. Scheduling Algorithm: Short Mode Start station: Station A - Vehicles: EV1(86%, 10:15), EV2(5%, 10:20), EV3(22%, 10:35) Step 4: Get available vehicles in Station A, with enough charge level Finish station: Station B Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-5. Scheduling Algorithm: Short Mode Start station: Station A - Vehicles: EV1(86%, 10:15), EV2(5%, 10:20), EV3(22%, 10:35) Step 5: Assign the candidate vehicle with the maximum charge level to the new trip Finish station: Station B Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 10:15 10:20 10:25 10:30 10:35 10:40 10:45 10:50 10:55 11:00 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-6. Scheduling Algorithm: Short Mode Advantages Fast execution Simple implementation Efficient for short term trip requests Disadvantages The algorithm searches for vehicles located in a Start station without future routes Assigned vehicles remain unavailable until their future trip is finished Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-7. Scheduling Algorithm: Long Mode Start station: Station A Step 1: Receive trip requests from customers Finish station: Station B 10:15 10:20 10:25 10:30 10:35 10:40 10:45 ... 12:55 13:00 10:15 10:20 10:25 10:30 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-8. Scheduling Algorithm: Long Mode Start station: Station A Step 2: Calculate trip duration and energy cost based on station coordinates Finish station: Station B - Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 ... 12:55 13:00 10:30 10:35 10:40 10:45 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-9. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV1(7%, 10:15), EV2(6%, 10:20), EV3(22%, 10:18) Step 3: Get available vehicles in Station A, before start time, without future routes Finish station: Station B - Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 ... 12:55 13:00 10:30 10:35 10:40 10:45 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-10. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV1(7%, 10:15), EV2(6%, 10:20), EV3(22%, 10:18) Step 4: Get available vehicles in Station A, with enough charge level Finish station: Station B - Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 ... 12:55 13:00 10:30 10:35 10:40 10:45 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-11. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV3(22%, arrives: 10:18, leaves: 12:55) Step 5: Get available vehicles in Station A, before start time, with 1 future route Finish station: Station B - Energy required for trip: 8% 10:15 10:20 10:25 10:30 10:35 10:40 10:45 ... 12:55 13:00 10:30 10:35 10:40 10:45 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-12. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV3(22%, arrives: 10:18, leaves: 12:55), EV4(20%, 12:10) Step 6: Get substitute vehicles in Station A, before EV3 start time, without future routes Finish station: Station B - Energy required for trip: 8% Substitute station: Station C 10:15 10:20 10:25 10:30 10:35 ... 12:10 12:55 13:00 10:30 10:35 10:40 10:45 11:20 11:25 11:30 11:35 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-13. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV3(22%, arrives: 10:18, leaves: 12:55), EV4(20%, 12:10) Step 7: Get substitute vehicles, with enough charge level for the EV3 future route Finish station: Station B - Energy required for trip: 8% Substitute station: Station C 10:15 10:20 10:25 10:30 10:35 ... 12:10 12:55 13:00 10:30 10:35 10:40 10:45 11:20 11:25 11:30 11:35 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-14. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV3(22%, 10:18), EV4(20%, arrives: 12:10, leaves: 12:55) Step 8: Assign the substitute vehicle EV4 to the future route of EV3, now EV3 is free Finish station: Station B - Energy required for trip: 8% Substitute station: Station C 10:15 10:20 10:25 10:30 10:35 ... 12:10 12:55 13:00 10:30 10:35 10:40 10:45 11:20 11:25 11:30 11:35 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-15. Scheduling Algorithm: Long Mode Start station: Station A - Vehicles: EV3(22%, 10:18), EV4(20%, arrives: 12:10, leaves: 12:55) Step 9: Assign the candidate vehicle with the maximum charge level to the new trip Finish station: Station B - Energy required for trip: 8% Substitute station: Station C 10:15 10:20 10:25 10:30 10:35 ... 12:10 12:55 13:00 10:30 10:35 10:40 10:45 11:20 11:25 11:30 11:35 Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

3-16. Scheduling Algorithm: Long Mode Advantages Fast execution It also considers the future routes of other vehicles It tries to find substitutes and make current assigned vehicles, free Efficient for both short and long term trip requests Disadvantages Complex implementation Implements only one swap between candidate and substitute vehicles Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-1. MoD Software Package Purpose A MoD company can monitor the state and locations of their EVs Station and customer data can be managed through an efficient UI Customers can make trip requests and bookings A central system integrates the Short Mode and Long Mode algorithms Ensuring that the highest number of people will be served in a given period Components Web Platform: to handle the MoD company activities and customer trip requests Mobile App: to handle customer activities, e.g. sending trip requests Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-2. MoD Software Package Architecture Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-3. MoD Software: Web Platform Administrator functionalities Upload map XML file with station coordinates Upload vehicle XML file with vehicle characteristics Manage user, station, vehicle and trip data Other functionalities Handle incoming customer trip requests Process the requests based on the Short Mode or Long Mode algorithm Accept or deny the trip requests Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-4. MoD Software: Web Platform Implemented with Java Spring MVC, a web framework with bundled modularity Spring Security, for authentication and authorization Spring Batch, for processing a high volume of batch operations RESTful web service, for sending stations data to the mobile app TCP connection, for accepting a large number of trip requests Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-5. MoD Software: Web Platform Architecture Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-6. MoD Software: Mobile App Customer functionalities Register and login to their profile Select start station, finish station and start time to request a trip See their history of the trip requests and their state (accepted or denied) Other functionalities Trip requests are sent to the web platform After the process by the web platform, the mobile app saves the state of the request (accepted or denied) Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-7. MoD Software: Mobile App Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-8. MoD Software: Mobile App Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

4-9. MoD Software: Mobile App Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-1. Testing and Evaluation Step 1: Station data are uploaded via an XML file with station coordinates Evaluation of algorithms with real data on MoD locations Coordinates of charging stations in Bristol are used for our stations 27 stations are selected for our paradigm The city is categorized into 5 traffic levels to resemble realistic travel conditions We assume that the stations nearest to the center have a higher number of requests 54 vehicles with their initial locations at the stations closer to the city center Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-2. Testing and Evaluation Step 2: Parameters to use when generating the trip requests Parameters examined during evaluation The maximum number of trip requests in a day The maximum time that a user is allowed to request a vehicle in the future The start times density factor, that essentially means how ”close” or how ”further away” in time, the start times of the trip requests are The number of available EVs in the current MoD scheme Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-3. Testing and Evaluation Step 3: Generate trip requests based on a mix of evaluation parameters Requests for trips generated with our “trip requests tool” Generated data: user id, start station id, finish station id, start time Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-4. Testing and Evaluation Step 4: Run simulations on web platform and evaluate both algorithms The efficiency rate is the % of the requests that get accepted and are actually scheduled We select ranges of each of the 4 parameters Generate 400 requests for trips for each range Input these requests to the web platform Let the Short Mode algorithm decide whether to accept or deny the requests Re-import the requests and let the Long Mode algorithm decide Document the results Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-5. Testing and Evaluation Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-6. Testing and Evaluation Observations Long Mode has average gain of 1.40% which translates to 8.88 more minutes of travel time for every 60 requests Long Mode has 17.8% higher execution times than Short Mode Simulation with 27 stations and 54 EVs Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-7. Testing and Evaluation Observations Long Mode has 2.84% higher efficiency rate when start times are equally shared When start times of the requests are closer, both algorithms show the same performance Simulation with 27 stations and 54 EVs Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-8. Testing and Evaluation Observations Long Mode average gain of 2.08% which translates to 32.5 more minutes of travel time for every 120 requests Long Mode has 2.87% higher utilization rate than Short Mode Simulation with 27 stations and 54 EVs Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-9. Testing and Evaluation Observations With 18 EVs the Long Mode has an average gain of 1.83% When the number of EVs increases, Long Mode performance increases up to 2.08% and then it remains constant This is expected, the Long Mode incorporates only one swap with a substitute vehicle Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

5-10. Testing and Evaluation Conclusions from observations The Long Mode algorithm performs better than the Short Mode in all tests The Long Mode offers more gain, when the number of requests increase When the maximum time between the start times of the requests increases, the efficiency increases When the number of requests within the day increases, the efficiency rate drops The Long Mode algorithm has the advantage of looking ahead for vehicles that can substitute a current candidate vehicle, so it results in better efficiency rate, but it incorporates only one such swap, so the gains are relatively small in percentage Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

6-1. Summary Summary We studied a setting where EVs can be hired to drive in an one-way MoD scheme We proposed two scheduling algorithms for assigning EVs to trips The Short Mode is efficient for short term reservations The Long Mode is efficient for both short and long term ones We designed, implemented and tested a system that consists of a web platform for administrators and a mobile app for customers Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

6-2. Summary Summary We evaluated our algorithms in a setting using real data on MoD locations The Long Mode shows an average gain of 2.08% in respect to the Short Mode This translates to 32.5 more minutes of travel time for every 120 requests It achieves 2.87% higher utilization rate than Short Mode It also enhances customer satisfaction, as it is related directly to the number of requests accepted by the system We provided a software package and an easy way to test evaluate algorithms towards efficient online EV scheduling for MoD schemes Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

6-3. Summary Video demo: https://youtu.be/flyixErIE-A Source code (web platform): https://github.com/ioannisgk/evsharing-platform3-release Source code (mobile app): https://github.com/ioannisgk/evsharing-app-release Ioannis Gkourtzounis, Emmanouil S. Rigas and Nick Bassiliades, EUMAS 2018

Thank you! Towards Online Electric Vehicle Scheduling for Mobility-On-Demand Schemes Ioannis Gkourtzounis - ioannisgk@live.com Emmanouil S. Rigas - erigas@csd.auth.gr Nick Bassiliades - nbassili@csd.auth.gr