Energy Savings by Optimization of Thrusters Allocation during Complex Ship Manoeuvres

The International Maritime Organization adopted a strategy to reduce the total annual GHG emissions from international shipping by at least 50% by 2050, compared to 2008 levels. The European Union proposed an even farther reaching transformation: the European Commission adopted a set of proposals to make the EU’s transport policies fit for reducing net greenhouse gas emissions by at least 55% by 2030, compared to 1990 levels. Therefore, all industrial actions in line and consistent with these strategies are essential. One of such activities may be a gradual transition from the most common independent controls of transport ships’ thrusters, propellers, and rudders to an integrated, power optimized, 3 degrees of freedom joystick control. In this paper, the full mission bridge simulator (FMBS) research on potential energy savings and, consequently, a GHG emission reduction, while steering a RoPax twin-screw ferry equipped with bow thrusters by a joystick control, is presented. The task of navigators engaged in the research was to steer the vessel either via classic engine, rudder, and thruster levers or via a joystick while (1) following the predefined straight track, (2) rotating at the turning area, and (3), finally, crabbing (moving sideways) until stopping at the quay fenders. The conclusions are that energy savings of approximately 10% can be expected for berthing manoeuvres controlled by a joystick, compared to independent actuators’ controls. These conclusions have been drawn from a statistical analysis of the ship’s energy consumption during typical manoeuvring phases of 18 berthing operations performed in FMBS.

Development of a Remote-Controlled Drone System by Using Only Eye Movements: Design of a Control Screen Considering Operability and Microsaccades

In recent years, the number of bedridden patients, including amyotrophic lateral sclerosis (ALS) patients, has been increasing with the aging of the population, owing to advances in medical and long-term care technology. Eye movements are physical functions that are relatively difficult to be affected, even if the symptoms of ALS progress. Focusing on this point, in this paper, in order to improve the quality of life (QOL) of bedridden patients, including ALS patients, we propose a drone system connected to the Internet that can be remotely controlled using only their eyes. In order to control the drone by using only their eyes, a control screen and an eye-tracking device were used in this system. By using this system, for example, the patients in New York can operate the drone in Kyoto using only their eyes, enjoy the scenery, and talk with people in Kyoto. In this drone system, since a time delay could occur depending on the Internet usage environment, agile operation is required for remotely controlling the drone. Therefore, we introduce the design of the control screen focused on remote control operability and human eye movements (microsaccades). Furthermore, considering the widespread future use of this system, it is desirable to use a commercial drone. Accordingly, we describe the design of a joystick control device to physically control the joysticks of various drone controllers. Finally, we present experimental results to verify the effectiveness of this system, including the control screen and the joystick control device.

Joystick Steering in Recreational Boats Using L1 Adaptive Control

This paper addresses the challenge of commissioning recreational boats with joystick control systems when the boat's physical parameters are not known. The work was conducted through matlab simulations and scale-model physical testing. The outcome is a working nonlinear, closed-loop control methodology shown on a small-scale prototype boat. The control methodology, L1 adaptive control (L1AC), provides adaptive velocity and angular velocity control. The control system delivers performance levels that could reduce the cost of commissioning boats with joystick control, improve overall performance, and potentially enable the technology to support new boat markets.

Control and Evaluation of a Motorized Attendant Wheelchair With Haptic Interface

Attendant wheelchairs provide a means to transport patients or mobility to people with walking disability. They can be attendant propelled, which are highly maneuverable in confined spaces, but offer no power assistance. Also, they can be electric powered with joystick control interface, which provides power assistance, but not as maneuverable as the attendant propelled wheelchair. With the objective of providing power assistance and having excellent maneuverability, this paper presents a motorized attendant wheelchair with haptic interface. Its control approach is based on virtual/desired dynamics, which is not the true dynamics of the wheelchair, but a mathematical model describing the motion behavior of a desired system. The desired dynamics takes the user's applied force/torque and yields desired velocities of the wheelchair. In the evaluation, tasks in confined spaces that require a lot of maneuvers were given and performed using the motorized wheelchair with haptic and joystick control interfaces. The results in terms of task completion times showed that motorized wheelchair with haptic significantly outperformed the motorized wheelchair with joystick interface. In addition, the performance of the motorized with haptic interface and attendant propelled wheelchairs were evaluated at two different loads. At heavy load, the task completion times of motorized wheelchair with haptic interface were comparable to the attendant propelled wheelchair.