# Case Study of an Integrated Design and Technical Concept for a Scalable Hyperloop System
## 5 Physical Definition
### Pods  
The pods consist of pressurized passenger or cargo modules mounted on service modules. The service module features most of the technical equipment, including the levitation, propulsion, and power supply system, while the passenger module runs the environmental control system and onboard electronics. A cargo module could be filled with pallets, Unit Load Devices (ULDs), or even a car.  
Figure 10 shows a rendering of a possible seating configuration in economy class. The volumes opposite the two doors can be used for a toilet, a luggage rack, a wheelchair, or bicycles. Table 11 summarizes the dimensions of the pod and the cabin. The entire passenger or cargo module is transportable by truck or container and can be manufactured similar to the pressurized compartments of airplanes.  
An important design decision is the aisle in the cabin. It is the driving factor for the diameter of the capsule and the tube. Without the aisle, every row of seats would require its own door, and an onboard toilet would be hardly possible. Additionally, the space helps create a comfortable atmosphere, which is crucial. Toilets could be excluded for shorter trips but are considered. People with reduced mobility are accommodated in boarding, seating, and emergency procedures.  
\begin{table}
\begin{tabular}{l c} \hline \hline
**Description** & **Value** \\ \hline Tube thickness & 0.15 m \\ Inner tube diameter (max speed) & 5.70 m \\ Cross-sectional area guideway (max speed) & 0.93 m\({}^{2}\) \\ BR (max speed) & 0.26 \\ Inner tube diameter (nom speed) & 5.10 m \\ Cross-sectional area guideway (nom speed) & 0.82 m\({}^{2}\) \\ BR (nom speed) & 0.33 \\ Tube span (pillar distance) & 35.00 m \\ Length of tube segment & 2.50 m \\ Concrete density & 2.30 \(\frac{1}{\text{m}^{3}}\) \\ Mass tube segment & 21.19 t \\ Mass tube span & 296.62 t \\ \hline \hline \end{tabular}
\end{table}
Table 10: Tube characteristics. Values with a grey background are calculated, while others are input values.  
The life support system of the passenger module cannot rely on bleed air like planes. Therefore, CO\({}_{2}\) scrubbers and HEPA filters will be integrated into the air conditioning system. Refilable oxygen bottles will compensate for the breathing of passengers. Pressure fluctuations will be controlled using an additional pressurized air bottle.  
Table 12 provides a feasibility check of the pod mass budget in absolute and relative numbers. Additionally, the mass of the distributed systems is divided by 14 (7 boogies with two drivetrain modules each) to see the mass budget per module.  
\begin{table}
\begin{tabular}{l c} \hline \hline
**Description** & **Value** \\ \hline Seats per pod & 21 \\ Cabin height (at aisle) & 1.90 m \\ Seat width & 0.46 m \\ Seat pitch & 0.86 m \\ Passenger module outer diameter & 2.50 m \\ Cabin length & 9.00 m \\ Pod length & 12.00 m \\ Pod cross-sectional area & 6.47 m\({}^{2}\) \\ \hline \hline \end{tabular}
\end{table}
Table 11: Pod dimensions.  
Figure 10: Rendering of a pod with maximum packaging for 21 passengers plus one person with reduced mobility in an isometric view (**A**) and front view (**B**).  
\begin{table}
\begin{tabular}{l c c} \hline \hline
**Description** & **Relative** & **Absolute** & **Value Per** \\  & **Value** & **Value** & **Module** \\ \hline Passenger + baggage per seat & & 100 kg \\ Passenger + baggage total & & 2100 kg \\ Interior + life support per seat & & 70 kg \\ Interior + life support total & & 1470 kg \\ Payload & 23.8\% & 3570 kg \\ Fairing & 3.3\% & 500 kg \\ Pressure vessel structure & 15.3\% & 2300 kg \\ Cooling & 4.7\% & 700 kg \\ Service module structure & 6.7\% & 1000 kg \\ Electronics (inverter, harness, communication, control) & 6.7\% & 1000 kg \\ Battery & 9.3\% & 1400 kg \\ EDS & 3.7\% & 550 kg \\ IPS & 1.9\% & 280 kg \\ Propulsion & 6.0\% & 900 kg \\ Levitation & 18.7\% & 2800 kg \\ \hline Total pod mass & & 15,000 kg \\ \hline \hline \end{tabular}
\end{table}
Table 12: Pod mass breakdown. Values with a grey background are calculated, while others are input values.