Opportunistic networking for improving the energy efficiency of multi-hop cellular networks
where mvehicle is vehicle mass, Jwheel is wheel inertia, Opportunistic networking for improving the energy efficiency of multi-hop cellular networks b is viscous damping coefficient, rwheel is wheel radiusis wheel speed, and are vehicle and wheel accelerations, respectively. Furthermore, fslip , faero, frolling are wheel slip, aerodynamic resistance, and rolling resistance forces, respectively, and τdifferential and τbrake are differential and brake torques, respectively, and they are given by is the normal tire force, is the friction coefficient, ,max is the wheel slip for force saturation, where A is the vehicle frontal area, ρair is the air density, Cd is the aerodynamic drag coefficient, and x˙ is vehicle velocity, where ai are empirical coefficients, and P is the tire pressure, and where is viscous damping coefficient, FCoulomb is the static Coulomb force, and cbrake is the brake command from the driver.
The parameter values are given in Table in the Appendix. Finally, this section describes the architecture used for communicating the coupling variables over the Internet between Warren and Ann Arbor. Opportunistic networking for improving the energy efficiency of multi-hop cellular networks Different communication architecturesexist in the literature, including both wave variable-based and event-based architectures. This work adopts an eventbased communication architecture similar to Xi and Tarn and Elhajj primarily because of its ease of practical implementation. The event-based framework may also have additional attractive stability-, transparency-, and synchronizationrelated properties under some assumptions of isomorphism between its “event domain” and the time domain.
Opportunistic networking for improving the energy efficiency of multi-hop cellular network
This paper does not explore the validity of these underlying assumptions in the context of ID-HIL simulation. Instead, it focuses on evaluating the transparency properties of the framework directly using experimental data. Ongoing work by the authors is also examining different approaches to improving these transparency properties, Warren site acts as the client and the Ann Arbor site acts as the server. Opportunistic networking for improving the energy efficiency of multi-hop cellular networks Warren site sends updated transmission speed and throttle signals at a frequency Communication flowchart for the Warren site. Communication flowchart for the Ann Arbor site. regardless of whether it receives a response or not. Ann Arbor site, on the other hand, only responds to the packets it receives, it only sends an updated transmission torque signal when it receives a packet from Warren. illustrate the communication flowcharts for Warren and Ann Arbor sites, respectively. The signals received at both sites are incorporated into the local models through filters to allow a smoother transition and protect the hardware.
Specifically, the Warren site uses a filter that linearly increases the transmission torque value from its previous value to its new value in The Ann Arbor site, on the other hand, uses a first order filter of the form with a time constant of and thus, a settling time of approximately. Therefore, on both sites, the signals reach their new values by the next communication event, which happens every according to the simulation clock of the Warren site. This paper does not consider synchronization of the clocks in the ID-HIL setup. It is acknowledged that working with asynchronous clocks may introduce further degradation in transparency, but it is also noted that such adverse effects of lack of synchronization will also be captured by the proposed transparency analysis. The communication is handled using the User Datagram Protocol UDP is preferred over the Transmission Control Protocol TCP in this work because of its minimalistic, expense of a guarantee of delivery, Opportunistic networking for improving the energy efficiency of multi-hop cellular networks ordering, or duplicate protection. This means that the packets may arrive out of order, in duplicates, or not at all, but as a benefit of this lack of network interface level error checks, the communication delay is reduced, which is more critical for the purposes of ID-HILS.