Abstract-Remote control of vehicles is a difficult task for operators. Support systems that present additional task information may assist operators, but their usefulness is expected to depend on several factors such as 1) the nature of conveyed information, 2) what modality it is conveyed through, and 3) the task difficulty. In an exploratory experiment, these three factors were manipulated to quantify their effects on operator behavior. Subjects (n = 15) used a haptic manipulator to steer a virtual nonholonomic vehicle through abstract environments, in which obstacles needed to be avoided. Both a simple support conveying near-future predictions of the trajectory of the vehicle and a more elaborate support that continuously suggests the path to be taken were designed (factor 1). These types of information were offered either with visual or haptic cues (factor 2). These four support systems were tested in four different abstracted environments with decreasing amount of allowed variability in realized trajectories (factor 3). The results show improvements for the simple support only when this information was presented visually, but not when offered haptically. For the elaborate support, equally large improvements for both modalities were found. This suggests that the elaborate support is better: additional information is key in improving performance in nonholonomic steering tasks.

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During operation of slow dynamic systems such as heavy machinery, users must account for inherent lag in the system dynamics, often via the less intuitive rate control mode. The slow response of these systems requires predictive control based on an understanding of the input-output relationship of system dynamics. In practical applications, such as learning to control an excavator, training can be a long and therefore costly process. This paper investigates the use of haptic shared control (HSC) to support learning of a system with slow dynamics. Previous work has failed to reach a consensus on the effectiveness of training with HSC, although a few recent studies have demonstrated improvements in tasks with timecritical components. Here, subjects learned to perform a pursuit task while controlling a linear system with slow dynamics using a 1-DOF haptic manipulator, either with or without HSC during training. To prevent reliance on the guidance forces, HSC was only present on intermittent trials and decreased in strength over time. Both groups quickly learned the task and showed similar performance after training, regardless of whether or not they trained with HSC.

Recent developments for deep-sea mining have shown multiple scenarios of gaining mineral deposits of Seafloor Massive Sulfides (SMS). One of the problems for these scenarios is the overall large energy consumption of processing rock material which are a technological challenge and are increasing production costs. This paper compares two methods for deep-sea rock excavation on their energy consumption, based on rudimentary calculations. The best known scenario for gaining mineral deposits from the seabed is to excavate rock materials with a crown or drum cutter and pump the fluidized crushed materials to the vessel at the surface. This process requires high cutting forces deep-sea due to the hyperbaric effect at large water depths, when cutting with full cavitation. This high energy consuming process therefore requires a considerable amount of subsea installed power. An alternative scenario is to use a hydraulic grab for excavating mineral deposits and not crush all the materials entirely subsea. Using a grab would be very beneficial in rough terrains and unstable seafloor conditions, compared to track-driven vehicles typically used for crown or drum cutters. Also specific cutting forces are much lower when using a grab, because it is not cutting at full cavitation in hyperbaric conditions. However the main advantage is to keep most of the rock intact which allows the material to be crushed at the surface. Mechanically uplifting large pieces of rock therefore could have the advantage that most of the required power can be installed at the surface, rather than subsea for the traditionally proposed hydraulic pumping systems. The rock can then be further crushed under atmospheric pressure at the surface, avoiding the hyperbaric effect. The combination of using a grab and further crushing at atmospheric conditions is more energy efficient and therefore requires substantially less installed subsea power. Using rudimentary calculations, a great reduction of energy consumption is found for using a grab compared to typically used crown or drum cutters. Substantially less subsea installed power is required for excavating the mineral deposits with a grab. Although additional crushing needs to be done at the surface, the overall required installed power for using a grab still can be much less than fully subsea excavating and crushing.