Abstract:A supportive mobile robot for assisting the elderly is an emerging requirement mainly in countries like Japan where population ageing become relevant in near future. Falls related injuries are considered as a critical issue when taking into account the physical health of older people. A personal assistive robot with the capability of picking up and carrying objects for long/short distances can be used to overcome or lessen this problem. Here, we design and introduce a 3D dynamic simulation of such an assistive robot to perform pick and place of objects through visual recognition. The robot consists of two major components; a robotic arm or manipulator to do the pick and place, and an omnidirectional wheeled robotic platform to support mobility. Both components are designed and operated according to their kinematics and dynamics and the controllers are integrated for the combined performance. The objective was to improve the ac-curacy of the robot at a considerably high speed. Designed mobile manipulator has been successfully tested and sim-ulated with a stereo vision system to perform object recognition and tracking in a virtual environment resembling aroom of an elderly care. The tracking accuracy of the mobile manipulator at an average speed of 0.5m/s is 90% and is well suited for the proposed application.

Abstract:The enhanced definition of Mechatronics involves the four underlying characteristics of integrated, unified, unique, and systematic approaches. In this realm, Mechatronics is not limited to electro-mechanical systems, in the mul-ti-physics sense, but involves other physical domains such as fluid and thermal. This paper summarizes the mecha-tronic approach to modeling. Linear graphs facilitate the development of state-space models of mechatronic systems, through this approach. The use of linear graphs in mechatronic modeling is outlined and an illustrative example of sound system modeling is given. Both time-domain and frequency-domain approaches are presented for the use of linear graphs. A mechatronic model of a multi-physics system may be simplified by converting all the physical do-mains into an equivalent single-domain system that is entirely in the output domain of the system. This approach of converting (transforming) physical domains is presented. An illustrative example of a pressure-controlled hydraulic actuator system that operates a mechanical load is given.

Abstract:In the process of crowd movement, pedestrians are often affected by their neighbors. In order to describe the consistency of adjacent individuals and collectivity of a group, this paper learns from the rules of the flocking behavior, such as segregation, alignment and cohesion, and proposes a method for crowd motion simulation based on the Boids model and social force model. Firstly, the perception area of individuals is divided into zone of segregation, alignment and cohesion. Secondly, the interactive force among individuals is calculated based upon the zone information, velocity vector and the group information. The interactive force among individuals is the synthesis of three forces: the repulsion force to avoid collisions, the alignment force to keep consistent with the velocity direction, and the attractive force to get close to the members of group. In segregation and alignment areas, the repulsion force and alignment force among pedestrians are limited by visual field factors. Finally, the interactive force among individuals, the driving force of destination and the repulsion force of obstacles work together to drive the behavior of crowd motion. The simulation results show that the proposed method can not only effectively simulate the interactive behavior between adjacent individuals but also the collective behavior of group.

Abstract:Air traffic control is an essential obligation in the aviation industry to have safe and efficient air transportation. Year by year, the workload and on-job-stress of the air traffic controllers are rapidly increasing due to the rapid growth of air traveling. Controllers are usually dealing with multiple aircrafts at a time and must make quick and accurate decisions to ensure the safety of aircrafts. Heavy workload and high responsibilities create air traffic control a stressful job that sometimes could be error-prone and time-consuming, since controlling and decision-making are solely dependent on human intelligence. To provide effective solutions for the mentioned on the job challenges of the controllers, this study proposed an intelligent virtual assistant system (IVAS) to assist the controllers thereby to reduce the controllers’ workload. Consisting of four main parts, which are voice recognition, display conversation on screen, task execution, and text to speech, the proposed system is developed with the aid of artificial intelligence (AI) techniques to make speedy decisions and be free of human interventions. IVAS is a computer-based system that can be activated by the voice of the air traffic controller and then appropriately assist to control the flight. IVAS identifies the words spoken by the controller and then a virtual assistant navigates to collect the data requested from the controllers, which allows additional or free time to the controllers to contemplate more on the work or could assist to another aircraft. The Google speech application programming interface (API) converts audio to text to recognize keywords. AI agent is trained using the Hidden marko model (HMM) algorithm such that it could learn the characteristics of the distinct voices of the controllers. At this stage, the proposed IVAS can be used to provide training for novice air traffic controllers effectively. The system is to be developed as a real-time system which could be used at the air traffic controlling base for actual traffic controlling purposes and the system is to be further upgraded to perform the task by recognizing keywords directly from the pilot voice command.

Abstract:Leg amputations are common in accidents and diseases. The present active bionic legs use Electromyography (EMG) signals in lower limbs (just before the location of the amputation) to generate active control signals. The active con-trol with EMGs greatly limits the potential of using these bionic legs because most accidents and diseases cause se-vere damages to tissues/muscles which originates EMG signals. As an alternative, the present research attempted to use an upper limb swing pattern to control an active bionic leg. A deep neural network (DNN) model is implemented to recognize the patterns in upper limb swing, and it is used to translate these signals into active control input of a bionic leg. The proposed approach can generate a full gait cycle within 1082 milliseconds, and it is comparable to the normal (a person without any disability) 1070 milliseconds gait cycle.

Abstract:To keep coal workers away from the hazardous area with frequent accidents such as the roof fall and rib spalling in an underground coalmine, we put forward the solution with robotized self-moving anchor-supporting unit. The existing research shows that the surrounding rock of the roadway has self-stability, and the early or late support is not conducive to the safe and reliable support of the roadway, so there is a problem of support opportunity. In order to study the supporting effect and the optimal supporting time of the above solution, we established the mechanical coupling model of surrounding rock and advance support, and investigated the surrounding rock deformation and advance support pressure distribution under different reserved roof subsidence by using the numerical simulation software FLAC3D. The results show that the deformation of surrounding rock increases and finally tends to a stable level with the increase of pre settlement of roadway roof, and when the pre settlement of roof is between 8-15mm, the vertical pressure of the top beam of advance support reaches the minimum value, about 0.58MPa. Based on the above research, we put forward the optimum supporting time in roadway excavation, and summarized the evaluation method based on the mechanical coupling model of surrounding rock-advance support.