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Automated shuttles are small, low-speed (generally less than 25 mph) vehicles that do not require a human operator, though to date all have included an onboard human attendant. This project aims to assess the limitations that the EasyMile EZ10 Gen 3 low-speed automated vehicle (LSAV) encountered while operating on public roadways. The primary interests are to evaluate the infrastructure elements that posed the most challenges for the LSAV during its deployment. Further, the EasyMile EZ10 Gen 3 is advertised as being capable of operating at SAE International Level 4 Automated Driving System capability in certain ODDs. Accordingly, the team deployed the LSAV with the expectation that it would be operated at SAE Level 2 capability. The human safety operator was required to intervene in scenarios beyond the vehicle’s automated functional capability. The results of this analysis indicated that the LSAV operated at a lower than expected speed, experienced a high frequency of disengagements, and had a regular need for safety operator intervention. These results suggest that the EZ10 Gen 3 vehicle is not yet operating at SAE International Level 4 capability on routes with moderate complexity.

Electric scooters (e-scooters) are gaining in popularity due to their availability, accessibility, and low cost. However, there has been little research on how e-scooters behave on the road and interact with other road users. The Virginia Tech Transportation Institute, teaming with State Farm, conducted an observational study on the Virginia Tech campus. Video data were gathered through instrumented fixed cameras located at various intersections and high-volume pedestrian areas. The analysis focused on times with a high volume of e-scooter riders, which was the period from 10:00 a.m. to 4:00 p.m. A total of 492 e-scooter trips were recorded, and 473 of those were analyzed. The analysis showed that e-scooters pose the most threat to pedestrians due to their higher speed and the greater vulnerability of pedestrians. The results also showed that the e-scooter riders adjusted their operation rules based on the traffic environment. These results suggest that it might be safer for e-scooters to be operated on designated lanes, bike lanes, or roadways with a speed limit of 25 mph or less. Additional countermeasures to separate e-scooter traffic from vehicles may be required on roadways with faster speed limits. Further research is needed to confirm these recommendations.

Membrane technologies have been widely applied in surface water treatment for drinking water purification. The main obstacles to the large scale application of membranes include membrane fouling, energy consumption and high investment. This study systematically investigated the performance of a hybrid system including in-situ coagulation and membrane module. The key parameters of a membrane system, including initial flux, operation mode (intermediate or continuous, time intervals, backwashing and aeration) was comprehensively investigated. In addition, the treatment performance in terms of turbidity, organic matter removal, membrane fouling and cleaning, and the effect of coagulants, were also studied. It was found that flat ceramic membranes with in-situ coagulation for surface water treatment performed much better without aeration and frequent backwashing, which gave interesting and important implications for future applications of a flat ceramic membrane, especially in drinking water purification. The hybrid system can achieve a high-water flux of 150 L/m2&middot, h (LMH) for 8 h operation without aeration and backwash. The removal of turbidity, UV254 and COD can achieve 99%, 85% and 81%, respectively. The cake layer on the membrane surface formed from the coagulation flocs turned out to prevent the membrane to be exposed to organic pollutant immediately which minimized the fouling problem. In addition, the fouling layer on the membrane surface can be easily cleaned by air scouring and backwash at the end of experiments, with a water flux recovery of higher than 90%. These results in this study provided an alternative strategy for membrane fouling control and energy conservation.