Boredom and Distraction in Multiple Unmanned Vehicle Supervisory Control

Operators currently controlling unmanned aerial vehicles report significant boredom, and such systems will likely become more automated in the future. Similar problems are found in process control, commercial aviation and medical settings. To examine the effect of boredom in such settings, a long-duration low-task-load experiment was conducted. Three low-task-load levels requiring operator input every 10, 20 or 30 min were tested in a 4-h study, using a multiple unmanned vehicle simulation environment that leverages decentralized algorithms for sometimes-imperfect vehicle scheduling. Reaction times to system-generated events generally decreased across the 4 h, as did participants' ability to maintain directed attention. Overall, the participants spent almost half of the time in a distracted state. The top performer spent the majority of time in directed and divided attention states. Unexpectedly, the second-best participant, only 1% worse than the top performer, was distracted for almost one-third of the experiment, but exhibited a periodic switching strategy, allowing himself to pay just enough attention to assist the automation when needed. Indeed, four of the five top performers were distracted for more than one-third of the time. These findings suggest that distraction due to boring, low-task-load environments can be effectively managed through efficient attention switching. Future work is needed to determine optimal frequency and duration of attention state switches, given various exogenous attributes, as well as individual variability. These findings have implications for the design of and personnel selection for supervisory control systems where operators monitor highly automated systems for long durations with only occasional or rare input.United States. Office of Naval Research. Multidisciplinary University Research Initiative (N00014-08-C-070

Proof-of-Concept Evaluation of a Low-Cost and Low-Weight Tractor for Small-Scale Farms

About 80% of farms in India are less than five acres in size and are cultivated by farmers who use bullocks for farming operations. Even the smallest tractors available in the Indian market are too expensive and large, and not designed to meet the unique requirements of these farmers. To address these needs, we have developed a proof-of-concept lightweight (350 kg) tractor in collaboration with Mahindra and Mahindra Limited, an Indian tractor manufacturer. Given the challenges of accurately predicting traction in Indian soils by applying existing terramechanics models, an alternative design approach based on Mohr-Coulomb soil-failure criterion is presented. Analysis of weight, power and drawbar of existing tractors on the market, a single wheel traction test, and a drawbar test of a proof-of-concept small tractor prototype suggest that ~200kg is the maximum drawbar force that could be achieved by a 350kg tractor of conventional design. In order to attain higher drawbar performance of 70% of the tractor weight needed for specific agricultural operations, additional design changes are required. An approach for increasing traction by adding tires is investigated and discussed. Additional research on weight distribution, dynamic drawbar testing and tread design is suggested as future work.MIT Tata Center for Technology and DesignMahindra Limite

Synthesis, Characterization, and Study of Catalytic Activity of Chiral Cu(II) and Ni(II) Salen Complexes in the α-Amino Acid C-α Alkylation Reaction

A new family of Cu(II) and Ni(II) salen complexes was synthesized and fully characterized through various physicochemical methods. Their catalytic activity was evaluated in the phase transfer Cα-alkylation reaction of the Schiff bases of D,L-alanine ester and benzaldehyde derivatives. It was found that the introduction of a chlorine atom into the ortho- and para-positions of the phenyl ring of the substrate resulted in an increase in both the chemical yield and the asymmetric induction (ee 66–98%). The highest enantiomeric excess was achieved in the case of a Cu(II) salen complex based on (S,S)-cyclohexanediamine and salicylaldehyde at −20 °C. The occurrence of a bulky substituent in the ligand present in the complexes led to a drastic decrease in ee and chemical yield. For instance, the introduction of bulky substituents at positions 3 and 5 of the phenyl ring of the catalyst resulted in a complete loss of the stereoselectivity control in the alkylation reaction