Research On Adaptive Control Strategy Of Double Triangle Boom Of Rock-drilling Robot

Using computer to realize the highly automation of hydraulic drill rig is a chief development of hydraulic rock drilling equipment, and double triangle boom is widely used in hydraulic drill rig for its fine behavior. Double triangle boom is a kind of directly positioning mechanism, it can remove the drill rod to a target position directly in its operating range. In order to avoid interference and realize direct and accurate positioning, it is necessary to control the boom to along a planed track precisely. Starting from the practical nonlinear object of the double triangle positioning mechanism, and aiming at the control for trajectory tracking and positioning of the boom, this paper makes research on identification, prediction and control of general nonlinear systems, and then uses the result back to the special object of the boom. The main contents are as follows.Firstly, the development of hydraulic rock-drilling equipment at home and abroad is surveyed, the status quo of the research on nonlinear control system is discussed, and the selection of the motion control strategy of double triangle boom is demonstrated, then the reasonableness of adopting adaptive control strategy is pointed out. Secondly, according to the structure and the motion characteristic of double triangle boom, a rectangular coordinates and a oblique coordinates are set up, then the dimension relation relevant to the boom is derived from geometrical analysis, thus laying the basis for the moving velocity programming of the supporting cylinders and the scale conversion in the measurement of the posture of the boom. Thirdly, by analyzing the motion characteristic of the boom, a method for the whole course moving velocity programming of the supporting cylinders of the boom is presented, and thereby the condition to control the boom for stable motion and directly positioning is created. Fourthly, starting with the basic equations of hydraulic systems, by modeling the boom and its hydraulic system in mechanism, a simplified model of the parallel translation linkage of the boom is obtained, and the four model forms of input-output continuous-time transfer function, continuous-time statespace expression, input-output discrete-time model and discrete-time statespace expression are deduced. By analyzing the structure of the boom and the load-bearing of the cylinders, the formulas and the methods for estimating the model parameters and the bearing force of the cylinders are presented. As a result, the foundation for the control system design and simulation is set up. Fifthly, after the recursive input-output models of deterministic and stochastic nonlinear systems being introduced, the existence theorem of the time-varying linear model for describing stochastic nonlinear systems is given and demonstrated. By analyzing the defect and in order to improve the behavior of the closed loop prediction of systems, three novel practical input-output discrete-time models: an inhomogeneous time-varying linear model, an inhomogeneous incremental time-varying linear model and an incremental simple linear regression model are put forward, the existence theorem of the three models are also given and demonstrated. Sixthly, in order to estimate the parameters of the incremental simple regression model, a projection algorithm and a weighted limited memory regression algorithm are deduced, and a new rolling multiple model weighted average algorithm is proposed. A recursive least squares with forgetting factor algorithm and a projection algorithm are also given to estimate the parameters of the inhomogeneous time-varying linear model and the inhomogeneous incremental time-varying linear model. The three models and therelative parameter estimation approach provide general systems with unknown structure with facilities for identification and prediction. Seventhly, as we know, the moving velocity of valve-controlled cylinders is approximately proportional to the input voltage of the servo amplifier of electro-hydraulic proportional valve when the cylinders are in st...