An Open-Sourced Network-Based Large-Scale Simulation Platform for Shared Mobility Operations

效果图

Background

Establish an open-sourced network-based simulation platform for shared mobility operations. The simulation explicitly characterizes drivers’ movements on road networks for trip delivery, idle cruising, and en-route pick-up.

Contributions

• We develop a comprehensive, multi-functional and open-sourced simulator for ride-sourcing service, which can be used by both researchers and industrial practitioners on a variety of operational tasks. The proposed simulation platform overcomes a few challenges faced by previous simulators, including the closeness to reality, representation of customers’ and drivers’ heterogeneous behaviors, generalization for different tasks.

• The simulator provide interfaces for the training and testing of different tasks, such as testing of optimization algorithms, training/testing of reinforcement learning based approaches for matching and repositioning, evaluations of economic models for equilibrium analysis and operational strategy designs.

• Based on a vehicle utilization based validation task, some RL based experiments, and one task for theoretical model evaluation, the simulator is validated to be effective and efficient for ride-sourcing related researches. In the future, the simulator can be easily modified for completing other tasks, such as dynamic pricing, ride-pooling service operations, control of shared autonomous vehicles, etc.

Install

  1. Download the code.

git clone git@github.com:HKU-Smart-Mobility-Lab/Transportation_Simulator.git

  1. Download the dependencies and libraries.

conda env create -f environment.yml

Download Data

Here, we provide you data for Manhattan that we used in our experiments. You can download it from Onedrive.(https://connecthkuhk-my.sharepoint.com/:f:/g/personal/ctj21_connect_hku_hk/EuHy9dMKNy1CkZf5K87GMlYBAI54ZPeGzjanbrpBTZO5CQ?e=95BBYF). And due to the data privacy, we can not provide you the data for Hong Kong and Chengdu.

Survey Data

We conducted a survey in NYC, and one hundred people participated in this survey. The content and results of the questionnaire can be found in the Survey_E-hailing_Taxi_Service_Studies.xlsx file. Hope that this data can help you for your research. And if you use these data in your research, please cite our paper: Feng S., Chen T., Zhang Y., Ke J.* & H. Yang, 2023. A multi-functional simulation platform for on-demand ride service operations. Preprint at ArXiv:2303.12336. https://doi.org/10.48550/arXiv.2303.12336.

File Structure

- simulator
-- input
  -- graph.graphml
  -- order.pickle
  -- driver_info.pickle
-- output
  -- some output files
-- test
  -- test scripts
-- utils
  -- driver_generation.py
  -- find_closest_point.py
  -- handle_raw_data.py
-- dispatch_alg.py
-- simulator_pattern.py
-- simulator_env.py
-- A2C.py
-- sarsa.py
-- main.py
-- config.py
-- LICENSE.md
-- api_doc.md
- readme.md
Data preparing

There are three files in 'input' directory. You can use the driver data and order data provided by us. Also, you can run python handle_raw_data.py to generate orders' information, run python driver_generation.py to generate drviers' information.

In config.py, you can set the parameters of the simulator.

't_initial' # start time of the simulation (s)
't_end'  # end time of the simulation (s)
'delta_t' # interval of the simulation (s) 
'vehicle_speed' # speed of vehicle (km / h)
'repo_speed'  # speed of reposition
'order_sample_ratio' # ratio of order sampling
'order_generation_mode'  # the mode of order generation
'driver_sample_ratio' : 1, # ratio of driver sampling
'maximum_wait_time_mean' : 300, # mean value of maximum waiting time
'maximum_wait_time_std' : 0, # variance of maximum waiting time
"maximum_pickup_time_passenger_can_tolerate_mean":float('inf'),  # s
"maximum_pickup_time_passenger_can_tolerate_std"
"maximum_price_passenger_can_tolerate_mean"
"maximum_price_passenger_can_tolerate_std"
'maximal_pickup_distance'  # km
'request_interval': 5,  #
'cruise_flag' :False, # 
'delivery_mode':'rg',
'pickup_mode':'rg',
'max_idle_time' : 1,
'cruise_mode': 'random',
'reposition_flag': False,
'eligible_time_for_reposition' : 10, # s
'reposition_mode': '',
'track_recording_flag' : True,
'driver_far_matching_cancel_prob_file' : 'driver_far_matching_cancel_prob',
'input_file_path':'input/dataset.csv',
'request_file_name' : 'input/order', #'toy_requests',
'driver_file_name' : 'input/driver_info',
'road_network_file_name' : 'road_network_information.pickle',
'dispatch_method': 'LD', #LD: lagarange decomposition method designed by Peibo Duan
# 'method': 'instant_reward_no_subway',
'simulator_mode' : 'toy_mode',
'experiment_mode' : 'train',
'driver_num':500,
'side':4, # grid side length
'price_per_km':5,  # ¥ / km
'road_information_mode':'load',
'north_lat': 40.8845,
'south_lat': 40.6968,
'east_lng': -74.0831,
'west_lng': -73.8414,
'rl_mode': 'reposition',  # reposition and matching
'method': 'sarsa_no_subway',  #  'sarsa_no_subway' / 'pickup_distance' / 'instant_reward_no_subway'   
'reposition_method' #2C_global_aware',  # A2C, A2C_global_aware, random_cruise, stay  
Real Road Network Module

We use osmnx to acquire the shortest path from the real world. You can set 'north_lat', 'south_lat', 'east_lng' and 'west_lng' in config.py , and you can get road network for the specified region.

Mongodb Module

If your road network is huge, yu can use mongodb to store the road network information and add index on node id which uniquely identifies a node on the road network. You can use the following code to connect your local database route_network and collection route_list which stores the information. After that, you can use find_one interface to achieve the shortest path list easily.

myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["route_network"]
mycollect = mydb['route_list']

re_data = {
            'node': str(ori_id) + str(dest_id)
        }
re = mycollect.find_one(re_data)
Price Module

You can set the maximum order price that is normally distributed and acceptable to passengers by modifing maximum_price_passenger_can_tolerate_mean' and maximum_price_passenger_can_tolerate_std.

Cruising and Repositioning Module
Dispatching Module

In dispatch_alg.py, we implement the function LD, we use binary map matching algorithm to dispatch orders.

Experiment

You can modify the parameters in config.py, and then excute python main.py. The records will be recorded in the directory named output.

Tutorials

Technical questions

We welcome your contributions.

Contributors

This simulator is supported by the Smart Mobility Lab at The Univerisity of Hong Kong and Intelligent Transportation Systems (ITS) Laboratory at The Hong Kong University of Science and Technology.

Ownership

The ownership of this repository is Prof. Hai Yang, Dr. Siyuan Feng from ITS Lab at The Hong Kong University of Science and Technology and Dr. Jintao Ke from SML at The Univerisity of Hong Kong.

Citing

If you use this simulator for academic research, you are highly encouraged to cite our paper:

Feng S., Chen T., Zhang Y., Ke J.* & H. Yang, 2023. A multi-functional simulation platform for on-demand ride service operations. Preprint at ArXiv:2303.12336. https://doi.org/10.48550/arXiv.2303.12336