Decoupled Ankle Rehabilitation Mechanisms’ Design And Application

One of the most rough problems for the patients who are suffering the ankle injuries especially for the hemiplegic after stroke is the ankle rehabilitation, while current ankle rehabilitative robots generally present single-function characteristic, different limbs coupled together and can’t fully satisfy rehabilitative robots’ comfort criterion etc. Based on the tractive therapy of Traditional Chinese Medicine, In this paper, we presented a novel mechanism used for ankle rehabilitation robot, linkage dimensions were optimized and a mutual rehabilitation interface system was established as well. Main contents of this paper are as follows:On the premise of introducing “The synthesis rule of limbs for decoupled translational parallel mechanism” and “The synthesis rule of limbs for decoupled rotational parallel mechanism”, Compared with the “Realization conditions of rotational degrees of freedom of the mechanism” and “Realization conditions of translational degrees of freedom of the mechanism”, Comprehensive application of “Selection criterion of the input pair”. Based on the screw theory, the type synthesis method of 2R1 T decoupled parallel mechanism theory(R means rotation, T means translation) has been presented. Its basic synthesis process was provided,corresponding examples are provided as well.According to the mechanisms’ DOF(degree of freedom), all the types of the branches can be determined, Select one type from them as the first branch, According to the decoupled translationalotational rules and Rotation Conditions, determine other branches’ type, confirm the limbs’ input pair and arrange limbs rationally, then many 2R1 T decoupled mechanisms can be gained according the above theory.Separate domestic and overseas currently ankle rehabilitative robots into 3 categories, compare and analyze their motions and rehabilitative process respectively, introduce the tractive therapy of Traditional Chinese Medicine, Compared with the rehabilitative norms of ankle, select the best one 2R1 T decoupled mechanism, gained according to the above theory, as the prototype for analyzing, Aimed at the decoupled mechanism, a parameter optimization method is presented, then based on the GA an example is proposed to illustrate the specific process.Based on the parameter optimization, basic 2R1 T model of the prototype is established by the modeling software, then via simulating, kinematics analysis is also provided, which accordingly demonstrates the feasibility of the prototype to be used as an ankle rehabilitation robot; by analyzing the prototype’s velocity and acceleration, discussing the mutative inertia of the prototype, prototype’s driving functions can be optimized, which makes it more conformed to rehabilitative robot comfort principles; According to the Labview software, interactively rehabilitative interfaces were established preliminarily, which tremendously improve the enjoyment during the rehabilitative process.