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Semi-trucks, specifically class-8 trucks, have recently become a platform of interest for autonomy systems. Platooning involves multiple trucks following each other in close proximity, with only the lead truck being manually driven and the rest being controlled autonomously. This approach to semi-truck autonomy is easily integrated on existing platforms, reduces delivery times, and reduces greenhouse gas emissions via fuel economy benefits. Level 1 SAE fuel studies were performed on class-8 trucks operating with the Auburn Cooperative Adaptive Cruise Control (CACC) system, and fuel savings up to 10-12% were seen. Enabling platooning autonomy required the use of radar, global positioning systems (GPS), and wireless vehicle-to-vehicle (V2V) communication. Poor measurements and state estimates can lead to incorrect or missing positioning data, which can lead to unnecessary dynamics and finally wasted fuel.

Power electronics is playing an increasingly important role in vehicle systems. The voltage rating of automotive power electronics is predominantly determined by the transient immunity requirement, which considerably exceeds the maximum operating voltages of 12V and 24V automotive power systems, and imposes a large cost penalty. In contrast, the emerging 42V systems require a much improved bus voltage regulation to maintain system affordability. In this paper, we introduce a new class of transient voltage suppressors termed as MOSTVS, which provides a more accurately controlled clamping voltage than the conventional Zener diodes and MOVs over a wide range of current and temperature. The new MOSTVS concept, based on power MOSFET and polysilicon thin-film technologies, makes it possible to relax the breakdown voltage requirement of automotive power electronics and result in significant cost reduction.

Autonomy for multiple trucks to drive in a fixed-headway platoon formation is achieved by adding precision GPS and V2V communications to a conventional adaptive cruise control (ACC) system. The performance of the Cooperative ACC (CACC) system depends heavily on the reliability of the underlying V2V communications network. Using data recorded on precision-instrumented trucks at both ACM and NCAT test tracks, we provide an understanding of various effects on V2V network performance: Occlusions - non-line-of-sight (NLOS) between the Tx and Rx antenna may cause network signal loss. Rain - water droplets in the air may cause network signal degradation. Antenna position - antennas at higher elevation may have less ground clutter to deal with. RF interference - interference may cause network packet loss. GPS outage - outages caused by tree cover, tunnels, etc. may result in degraded performance. Road curvature - curves may affect antenna diversity.