Research On The Highly-Simulated Chewing Platform Of Food Materials

The food development, storage and keeping, as well as the trade and distribution are closely bound up with the evaluation on the food texture. The physical character detection is one of the most important parts of food texture evaluation, which includes the detection on the food features of hardness, viscoelastic, crisp, resistance to chew, and etc. All of these play an important guiding role in human diet health. Due to the different test environments, test parameters, oral cavity structures, and chewing behaviors, the food properties inspection instruments, which are widely used today, usually provide different property readings than human being’s actual tastes and feelings. Evaluations by test panels also have various disadvantages of being expensive, not efficient, and hard to be standardized. In view of such a situation, to develop chewing robot imitating humans chewing movement is especially important.The paper aims for designing a highly-simulated chewing platform which can imitate mandibular movement in performance, and put forward a structure design applying classical Stewart parallel structure to six-degree-of-freedom chewing movement. At the same time, the paper is aimed to do research on a series of kinematics and dynamics of the highly-simulated chewing platform, to prove that the design scheme is practical.1. Referring to characteristics of human’s chewing movement and applying six-of-freedom parallel robot technology, the model of chewing simulation platform was designed. After having a detailed understanding of the required mathematics basic knowledge of parallel mechanism researching and considering that the high dexterity is the important indicator of chewing movement, then based on Jacobian matrix about the speed, did local dexterity analysis of parallel-drive structure, thus the main structure parameter was confirmed. For ease of explaining space position change, applicable coordinate system was established, and kinematics including location, speed and acceleration was analyzed. In stationary state, the static equilibrium relevance between force on the end of the actuator and driving force of the joints was exported, thus Jacobian matrix was reached.2. On the basis of the inverse position kinematics solution, combining the influence factors of workspace and mandibular movement trajectory and scope; respectively on condition that giving a certain attitude and the given collection, the search of workspace was got by adopting multilayer nested loop. Through the research of the workspace of the selected reference point, change rule of workspace was analyzed. As can be seen from the analysis results, the workspace of the robot change regularly and the size can meet with the human’s masticatory movement range.3. Lagrange method was selected to build a dynamic model of the simulated chewing platform. After defining generalized coordinates, as well as considering load, did detailed deduction on the parameter of the system of kinetic energy and potential energy, then inputted the relevant calculation results and deduced each item of kinetics equation. Establishing the kinetics equation of the simulated chewing platform plays a certain guiding role in building other dynamic model of parallel mechanism.4. In the ADAMS condition, set up the virtual prototype model of the simulated chewing platform, gave examples of moving platform simulating specific human chewing movement, then simulated the virtual prototype to get some results. At the same time, the simulation results can not only indicate the robot has a good performance but also lay a good foundation for the research of high quality control method.