**3.2 Quality of service: four components**

Whatever the means of transportation - shuttle, taxi, car share, moped, bicycle, scooter etc. – users expect a satisfactory quality of service. While the quality of service has been adequately defined and described for collective transit systems in the Transit Capacity and Quality of Service Manual [11], for shared mobility services that are more diverse a more generic definition is required. To that end, an analysis framework comprising four components was put forward as follows [4]:


come to them, so the access time depends on the operating speed. For selfservice solutions, users must arrive at the vehicle, which implies walking pace. In both cases, the initial distance between the user and the service plays an important role: it will depend on the number of vehicles in service, their level of occupancy and the size of the ring network.

As for the fleet of vehicles, let us assume that it represents modal homogeneity. Each vehicle is capable of travelling at an average speed of *v*0. The size of the vehicle will depend on the mode of transportation: let *K* represent the number of places on board. For two-wheeled vehicles *K* ¼ 1, whereas *K* ¼ 4 or thereabouts for cars and *K* ¼ 12 for shuttle buses. Each vehicle is shared, in that it constitutes a component

• Each vehicle runs productively, in cyclical fashion, with an average workload

• Each point receives a guaranteed frequency of service (for shuttles), or else the availability across the whole zone is homogenous (for shared vehicles). This

• Multi-passenger vehicles can be pooled without the need for a detour: the only condition is that the vehicle must stop to let passengers come on and off. These elementary logistical tasks are distributed between the vehicles in circulation.

The average distance of the rides made by passengers, which we can denote as *LR* for ride length, is a factor in the rate of occupancy of vehicles, and also of the exposure of passengers to the delays required for other passengers to board and alight the service. Average operating speed *v* depends on all of the factors mentioned above:

• In terms of infrastructure, the circumference *C* and the speed of travel *v*0,

• In terms of the vehicles themselves, the passenger capacity *K* and the time

• In terms of the overall service, the size of the fleet *N* and the number of hours

There exists a substantial body of knowledge, theoretical as well as methodological, to design transportation networks and services. The classical textbook [12] provides travel demand models for traffic simulation, therefore enabling for traffic and revenue forecasting. Its domain of application encompasses roadway networks and public transport networks involving lines. The more advanced book [13] also considers more diverse forms of public transport, including on-demand services (chapter 8): on representing service operations, the production costs can be modelled,

As the said models of travel demand and transportation supply involve spatial finesse, they are solved numerically. The set of analytical conditions to depict e.g. an optimal system state is typically very large so that little insight might be gained from its inspection. By contrast, the models presented hereafter are analytical, owing to the postulates of ring shape and, more generally, homogeneity in space and time. Then, the models are endowed with circular symmetry, which is crucial to characterise the system state in a simple way and to obtain the few system state variables as easy-to-interpret analytical formulas of the model parameters.

too, and compared to service revenues in order to assess service profitability.

• In terms of demand, the volume *Q* and the average ride length *LR*,

taken for passengers to alight/board the service *t*S,

H for which the service runs during the day.

**4. Technical and economic modelling**

**171**

Keeping the fleet of vehicles attached to the ring circuit ensures that:

means that any user can access the service at any point.

of a fleet whose total size is *N*.

*Towards Shared Mobility Services in Ring Shape DOI: http://dx.doi.org/10.5772/intechopen.94410*

of *Q=N* trips per day.

This Availability category might also include the transaction operations between users and the service: information, pricing, payment and invoicing, reserving a vehicle or selecting a destination for taxi and shuttle services. It falls to the operator to simplify the corresponding tasks required of users as far as possible.

### **3.3 Ring-shaped services and quality of service**

**Conductance**. Running vehicles on a ring-shaped line avoids wasting time on detours, pick-ups and set-downs outside the designated circuit. This allows us to optimise the *availability* of each vehicle in service, and thus maximise the availability of the service for potential users.

Avoiding detours helps to increase the *speed* of journeys made on the ring. Speed also depends upon infrastructure design on the ground, with certain measures which may be taken to improve the fluidity of travel. Considering the best interests of the circuit as a whole, it is advisable to decide upon a suitable speed of travel, determined with reference to the urban environment and in order to satisfy all users and occupants of the space.

**Pleasure**. *Protection and comfort* depend first and foremost on the vehicles used: when determining which vehicles to acquire for the service, a number of specifications should be outlined in this respect. The design of the infrastructure also plays a role in ensuring the safety of individuals, ensuring that there is sufficient space for vehicles to move, guaranteeing sufficient visibility, smoothing out potential problem points and using appropriate signage to draw attention to them.

**Maintenance**. This depends on the preventive and curative measures taken by service operators, as well as the behaviour of passengers, other road users and residents. The ring format facilitates the logistics of curative interventions. It also lends itself to CCTV surveillance and on-site surveillance: these functions could well be integrated into the broader system of surveillance for the city's traffic and parking.

**Ease of use**. It is worth focusing in particular on the *availability* of the service: it will depend upon the ratio between the level of demand and the size of the fleet, among other factors including the circumference of the ring, the average distance travelled by passengers and the operating speed. The complex interplay of these factors is rendered more complex still by the fact that quality of service will have an influence on the level of demand. This is why we have developed specific technical and economic models for mobility services in ring form.

#### **3.4 Technical principles**

Combining a ring-shaped format with a fleet of vehicles provides significant opportunities for synergy. The ring circuit connects a number of points distributed along its circumference (*C*), attracting users from a band which is 2ℓ wide, with ℓ the range of attraction either side of the circuit. This ring has the potential to attract a certain amount of demand: let us call it *Q* number of journeys for each day the service is operational. The ring connects locations on a point to point basis: this function is clear when shown on a map, and must be obvious (legible) on the ground. Along the route, we can distribute logistical functions such as parking bays, recharging stations and cleaning stations, located together or separately as required. *Towards Shared Mobility Services in Ring Shape DOI: http://dx.doi.org/10.5772/intechopen.94410*

come to them, so the access time depends on the operating speed. For selfservice solutions, users must arrive at the vehicle, which implies walking pace. In both cases, the initial distance between the user and the service plays an important role: it will depend on the number of vehicles in service, their level

This Availability category might also include the transaction operations between

**Conductance**. Running vehicles on a ring-shaped line avoids wasting time on detours, pick-ups and set-downs outside the designated circuit. This allows us to optimise the *availability* of each vehicle in service, and thus maximise the avail-

Avoiding detours helps to increase the *speed* of journeys made on the ring. Speed

also depends upon infrastructure design on the ground, with certain measures which may be taken to improve the fluidity of travel. Considering the best interests of the circuit as a whole, it is advisable to decide upon a suitable speed of travel, determined with reference to the urban environment and in order to satisfy all users

**Pleasure**. *Protection and comfort* depend first and foremost on the vehicles used: when determining which vehicles to acquire for the service, a number of specifications should be outlined in this respect. The design of the infrastructure also plays a role in ensuring the safety of individuals, ensuring that there is sufficient space for vehicles to move, guaranteeing sufficient visibility, smoothing out potential problem points and using appropriate signage to draw attention to them. **Maintenance**. This depends on the preventive and curative measures taken by service operators, as well as the behaviour of passengers, other road users and residents. The ring format facilitates the logistics of curative interventions. It also lends itself to CCTV surveillance and on-site surveillance: these functions could well be integrated into the broader system of surveillance for the city's traffic and parking. **Ease of use**. It is worth focusing in particular on the *availability* of the service: it will depend upon the ratio between the level of demand and the size of the fleet, among other factors including the circumference of the ring, the average distance travelled by passengers and the operating speed. The complex interplay of these factors is rendered more complex still by the fact that quality of service will have an influence on the level of demand. This is why we have developed specific technical

Combining a ring-shaped format with a fleet of vehicles provides significant opportunities for synergy. The ring circuit connects a number of points distributed along its circumference (*C*), attracting users from a band which is 2ℓ wide, with ℓ the range of attraction either side of the circuit. This ring has the potential to attract a certain amount of demand: let us call it *Q* number of journeys for each day the service is operational. The ring connects locations on a point to point basis: this function is clear when shown on a map, and must be obvious (legible) on the ground. Along the route, we can distribute logistical functions such as parking bays, recharging stations and cleaning stations, located together or separately as required.

users and the service: information, pricing, payment and invoicing, reserving a vehicle or selecting a destination for taxi and shuttle services. It falls to the operator

to simplify the corresponding tasks required of users as far as possible.

*Models and Technologies for Smart, Sustainable and Safe Transportation Systems*

of occupancy and the size of the ring network.

**3.3 Ring-shaped services and quality of service**

and economic models for mobility services in ring form.

ability of the service for potential users.

and occupants of the space.

**3.4 Technical principles**

**170**

As for the fleet of vehicles, let us assume that it represents modal homogeneity. Each vehicle is capable of travelling at an average speed of *v*0. The size of the vehicle will depend on the mode of transportation: let *K* represent the number of places on board. For two-wheeled vehicles *K* ¼ 1, whereas *K* ¼ 4 or thereabouts for cars and *K* ¼ 12 for shuttle buses. Each vehicle is shared, in that it constitutes a component of a fleet whose total size is *N*.

Keeping the fleet of vehicles attached to the ring circuit ensures that:


The average distance of the rides made by passengers, which we can denote as *LR* for ride length, is a factor in the rate of occupancy of vehicles, and also of the exposure of passengers to the delays required for other passengers to board and alight the service.

Average operating speed *v* depends on all of the factors mentioned above:


## **4. Technical and economic modelling**

There exists a substantial body of knowledge, theoretical as well as methodological, to design transportation networks and services. The classical textbook [12] provides travel demand models for traffic simulation, therefore enabling for traffic and revenue forecasting. Its domain of application encompasses roadway networks and public transport networks involving lines. The more advanced book [13] also considers more diverse forms of public transport, including on-demand services (chapter 8): on representing service operations, the production costs can be modelled, too, and compared to service revenues in order to assess service profitability.

As the said models of travel demand and transportation supply involve spatial finesse, they are solved numerically. The set of analytical conditions to depict e.g. an optimal system state is typically very large so that little insight might be gained from its inspection. By contrast, the models presented hereafter are analytical, owing to the postulates of ring shape and, more generally, homogeneity in space and time. Then, the models are endowed with circular symmetry, which is crucial to characterise the system state in a simple way and to obtain the few system state variables as easy-to-interpret analytical formulas of the model parameters.
