Adaptive Backstepping Sliding Mode Control of Trajectory Tracking for Robotic Manipulators

To achieve precise trajectory tracking of robotic manipulators in complex environment, the precise dynamic model, parameters identification, nonlinear characteristics, and disturbances are the factors that should be solved. Although parameters identification and adaptive estimate method were proposed for robotic control in many literature studies, the essential factors, such as coupling and friction, are rarely mentioned as it is difficult to build the precise dynamic model of the robotic manipulator. An adaptive backstepping sliding mode control is proposed to solve the precise trajectory tracking under external disturbances with complex environment, and the dynamic response characteristics of a two-link robotic manipulator are described in this paper. First, the Lagrange kinetic method is used to derive the precise dynamic model which includes the nonlinear factor with friction and coupling. Moreover, the dynamic model of two-link robotic manipulator is built. Second, the estimate function for the nonlinear part is selected, and backstepping algorithm is used for analyzing the stabilities of the sliding mode controller by using Lyapunov theory. Furthermore, the convergence of the proposed controller is verified subject to the external disturbance. At last, numerical simulation results are reported to demonstrate the effectiveness of the proposed method

Constant Force PID Control for Robotic Manipulator Based on Fuzzy Neural Network Algorithm

The increased demand for robotic manipulator has driven the development of industrial manufacturing. In particular, the trajectory tracking and contact constant force control of the robotic manipulator for the working environment under contact condition has become popular because of its high precision and quality operation. However, the two factors are opposite, that is to say, to maintain constant force control, it is necessary to make limited adjustment to the trajectory. It is difficult for the traditional PID controller because of the complexity parameters and nonlinear characteristics. In order to overcome this issue, a PID controller based on fuzzy neural network algorithm is developed in this paper for tracking the trajectory and contact constant force simultaneously. Firstly, the kinetic and potential energy is calculated, and the Lagrange function is constructed for a two-link robotic manipulator. Furthermore, a precise dynamic model is built for analyzing. Secondly, fuzzy neural network algorithm is proposed, and two kinds of turning parameters are derived for trajectory tracking and contact constant force control. Finally, numerical simulation results are reported to demonstrate the effectiveness of the proposed method

Real Life Nutrition Assessment

The aim of this case study is to improve the current snack program in Sandpiper Child Care Services Centre in order to provide nutritionally adequate snacks to the children. The study follows the five-step nutrition care process (NCP), and dietary and ecological assessment are chosen as our areas of focus. Snack calendars provided by the childcare center are analyzed for the nutrition and energy content of each snack item, and surveys are conducted with the staff about their nutritional education background. From the assessment, we discovered the limited incorporation of all four food groups in snack preparation as well as a lack of awareness of healthy snack preparation amongst the child care staffs. From the assessment and the analysis of the results, a PES statement is developed: Imbalanced macronutrient intake related to childcare staffs’ lack of nutritional knowledge evidenced by low awareness of balanced diet in staff reported in surveying and lack of variety in food group selections in snack preparation. In order to improve the current situation, short-term and long-term intervention plans are proposed. Regarding short-term, alternative recipes with nutrient dense snacks are provided. On the other hand, for long-term, nutrition workshops for the staff every 6 months are suggested to refresh their nutritional knowledge. The goal of the interventions would be to improve staff’s nutrition knowledge and promote healthy eating habits in the children at the childcare. The same questionnaire used in assessment will be redistributed to staffs after interventions for monitoring purposes. Even though there are limitations in the case study, such as the limited representation of children’s dietary habits due to restricted observation opportunities, this study hopes to increase the awareness of providing nutritious food in childcare centres of the general public especially the childcare centres’ stakeholders, which are the parents and child care staffs. Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”Land and Food Systems, Faculty ofUnreviewedUndergraduat