Autonomous Vehicle technology is quickly expanding its market and has found in Silicon Valley, California, a strong foothold for preliminary testing on public roads. In an effort to promote safety and transparency to consumers, the California Department of Motor Vehicles has mandated that reports of accidents involving autonomous vehicles be drafted and made available to the public. The present work shows an in-depth analysis of the accident reports filed by different manufacturers that are testing autonomous vehicles in California (testing data from September 2014 to March 2017). The data provides important information on autonomous vehicles accidents’ dynamics, related to the most frequent types of collisions and impacts, accident frequencies, and other contributing factors. The study also explores important implications related to future testing and validation of semi-autonomous vehicles, tracing the investigation back to current literature as well as to the current regulatory panorama.

Equations are derived to predict the electrical behavior of a threephase superconducting alternator connected to a full-wave bridge rectifier. This is accomplished by expanding a previous analysis for conventional rectified alternators and adding computational improvements. The significance of the work is that it provides a means of calculating certain critical variables such as the ac current in the superconducting field winding and the ac voltage harmonics at the rectified output. A numerical example based on a machine designed for airborne applications is included.Recent advancements in superconducting alternators have created a strong interest in using these machines for airborne electric power supplies. The predominant advantage of this power source is its relatively low weight for applications requiring multimegawatt outputs at several kilovolts. This low weight characteristic occurs because of two factors: 1) even with the required cryogenic equipment, the superconducting alternator system weighs much less than a conventional altemator; 2) the higher armature voltages of the superconducting machine may eliminate the need for heavy output inverters and transformers. These low weight, high voltage attributes are discussed in further detail in [1 ] through [12]. A very recent example of such a machine is also described by McCabria et al. in [13]. This particular machine develops 10 MVA at 5 kV and weighs approximately 1000 lbs (alternator weight only). This same reference also includes projected estirnates for a 25 MVA machine weighing between 1882 and 2160 lbs, depending on rated output voltage (again, these figures only include the weight of the alternator).The potential advantages of superconducting alternators have prompted extensive research in this area, most of which has concentrated on ac loads (again see [1 ] through [13]). Applications for these machines also exist in high power dc systems, however, where the alternator is connected to a rectifier bridge followed by a large filter choke. This mode of operation has been studied in detail for conventional alternators (see [14] through [17]), but until now, no such analysis has been presented for the superconducting machine.One of the more rigorous analyses of conventional rectified alternators is that presented by Franklin [16], [17] for salient pole machines. By assuming constant flux linkages for the rotor windings, this study derives a set of nonlinear equations in terms of the electrical variables of interest. Certain approximations then lead to a linearization involving a constant K factor, and an explicit solution is obtained. The advantages of this approach are readily apparent since it provides a closed form expression for each of the variables, once the proper K factor has been found. The determination ofK is somewhat distracting, however, since it is load dependent and requires the use of numerical methods. In the following section it will be shown that this K factor can actually be eliminated from the final solution if a Newton-Raphson alg...

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The authors are with the Department of Electrical Engiaeering, Unithe demerit of small AT in V band. Second, the &e width about versity of Toledo, Toledo, OH 43606.