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SUMMARYThis paper tackles the problem of motion planning and control of a car-like robot in an obstacle-ridden workspace. A kinematic model of the vehicle, governed by a homogeneous system of first-order differential equations, is used. A solution to the multi-tasking problem of target convergence, obstacle avoidance, and posture control is then proposed. The approach of solving the problem is two-fold. Firstly, a novel velocity algorithm is proposed to drive the car-like robot from its initial position to the target position. Secondly, a single layer artificial neural network is trained to avoid disc-shaped obstacles and provide corresponding weights, which are then used to develop a function for the steering angles. Thus, our method does not need a priori knowledge of the environment except for the goal position. With the help of the Direct Method of Lyapunov, it is shown that the proposed forms of the velocity and steering angle ensure point stability. For posture stability, we model the two parallel boundaries of a row-structured parking bay as continua of disk-shaped obstacles. Thus, our method is extendable to ensuring posture stability, which gives the desired final orientation. Computer simulations of the generated path are presented to illustrate the effectiveness of the method.

SUMMARYThis paper formulates a new scalable algorithm for motion planning and control of multiple point-mass robots. These autonomous robots are designated to move safely to their goals in a priori known workspace cluttered with fixed and moving obstacles of arbitrary positions and sizes. The control laws proposed for obstacle and collision avoidance and target convergence ensure that the equilibrium point of the given system is asymptotically stable. Computer simulations with the proposed technique and applications to a team of two planar (RP) manipulators working together in a common workspace are presented. Also, the robustness of the system in the presence of noise is verified through simulations.

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Poor achievement in mathematics is an issue of great concern for many countries across the globe. Fiji is one of the countries in the South Pacific experiencing the same trends, pressures, and concerns. This study aims to seek the views of stakeholders (students, teachers, heads of departments, and school heads) with regards to the causes of poor achievement in mathematics at the senior grades of secondary schools in the districts of Ba and Tavua, Fiji. A descriptive design using both quantitative and qualitative approaches were utilized whereby data were collected from 201 upper secondary school respondents comprising 171 students, 16 mathematics teachers, 7 department heads, and 7 school heads from seven randomly selected schools in the districts of Ba and Tavua. The study found that the students had a negative attitude toward mathematics. It was also found that an ineffective mathematics curriculum in secondary schools was the reason behind poor performance in the subject. Moreover, many of the primary school teachers lacked potential and competence to teach mathematics at primary school levels, and this largely contributed toward the lack of interest amongst students, hence translating into poor achievement at both upper and lower secondary levels. On the other hand, however, it was gathered that secondary school teachers were rather positive, good quality, performing, and fully qualified as far as the teaching of mathematics and delivery of the subject matter was concerned. Review and amendments to the year 12 and 13 mathematics curriculum, use of technologies to teach mathematics, improving the quality of primary school mathematics teachers, reducing the emphasis on exams, introducing internal assessments, projects, and field work in the mathematics curriculum were a few of the significant recommendations made from this study.