# Conceptual Design Optimization of Autonomous Electric Buses in Public Transportation

^{1}

^{2}

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## Abstract

**:**

## 1. Introduction

## 2. Methodology

#### 2.1. Derivation of Properties

#### 2.2. Formulation of the Objective Function

#### 2.3. Implementation of Simulation Models

#### 2.3.1. Inputs

#### 2.3.2. Package Calculation

#### 2.3.3. Vehicle Scheduling

#### 2.3.4. Route Simulation

#### 2.3.5. Longitudinal Dynamics Simulation

#### 2.3.6. Vehicle Assignment

#### 2.3.7. Lifecycle Cost Assessment (LCCA) Model

#### 2.3.8. Lifecycle Assessment Model (LCA)

_{2}/passenger-km.

#### 2.3.9. Property Evaluation and Parameter Variation

## 3. Case Study

## 4. Results

_{2}/passenger-km for vehicle sizes of 94 and 20 passengers, respectively, as shown in Figure 12b.

## 5. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 2.**Value Functions showing the correlation between the objective value and technical specifications. Value function of (

**a**) waiting time, (

**b**) seating ratio, (

**c**) seat pitch, (

**d**) standing space, (

**e**) vehicle top speed, (

**f**) wheelchair zones.

**Figure 5.**Determination of departure times using the graphical method in [46].

**Figure 6.**Powertrain Architectures of single motor rear wheel drive (

**a**) and (

**b**) dual wheel-hub motors.

**Figure 7.**Showing the vehicle schedule and the state of charge (top), and the location and trips assigned to the vehicle during the day (bottom).

**Figure 9.**(

**a**) Pareto optimal solutions of the vehicle concepts for the analyzed route. (

**b**) The effect of vehicle size on the costs and value to the users.

**Figure 11.**Influence of vehicle size on (

**a**) passenger waiting time, and (

**b**) number of scheduled trips.

Property | Attributes |
---|---|

Service Performance | Waiting time Travel time Seat availability |

Accessibility | Entry height Wheelchair zones Number of doors |

Comfort | Seat width Legroom Standing space Headroom Thermal comfort Ride comfort |

Functionality | Luggage storage Power outlets Bicycle storage |

Information | Human-machine interfaces |

Safety | Handrails and handles Seatbelts Security/surveillance cameras |

Longitudinal Dynamics | Top speed Acceleration Gradeability |

Environmental Performance | Lifecycle greenhouse gas emissions |

Costs | Total Cost of Ownership |

Vehicle Parameters | Lower Bound | Upper Bound | Type |
---|---|---|---|

Vehicle Height | 2100 mm | 3000 mm | Continuous |

Vehicle Length | 5000 mm | 13000 mm | Continuous |

Vehicle Width | 2500 mm | 2600 mm | Continuous |

Interior Layout | Layout 1 | Layout 2 | Categorical |

Wheelbase | 2500 mm | 9000 mm | Continuous |

Seat Pitch | 650 mm | 850 mm | Continuous |

Seat Width | 400 mm | 550 mm | Continuous |

Standing Space | 2 Passengers/m^{2} | 8 Passengers/m^{2} | Continuous |

Powertrain Topology | Topology 1 | Topology 2 | Categorical |

Total Power | 40 kW | 400 kW | Continuous |

Gear Ratio | 1 | 30 | Continuous |

Battery Capacity | 30 kWh | 350 kWh | Continuous |

Wheelchair Zones | 0 | 2 | Discrete |

Number of Doors | 1 | 2 | Discrete |

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**MDPI and ACS Style**

Pathak, A.; Scheuermann, S.; Ongel, A.; Lienkamp, M.
Conceptual Design Optimization of Autonomous Electric Buses in Public Transportation. *World Electr. Veh. J.* **2021**, *12*, 30.
https://doi.org/10.3390/wevj12010030

**AMA Style**

Pathak A, Scheuermann S, Ongel A, Lienkamp M.
Conceptual Design Optimization of Autonomous Electric Buses in Public Transportation. *World Electric Vehicle Journal*. 2021; 12(1):30.
https://doi.org/10.3390/wevj12010030

**Chicago/Turabian Style**

Pathak, Aditya, Silvan Scheuermann, Aybike Ongel, and Markus Lienkamp.
2021. "Conceptual Design Optimization of Autonomous Electric Buses in Public Transportation" *World Electric Vehicle Journal* 12, no. 1: 30.
https://doi.org/10.3390/wevj12010030