No abstract

Recently the necessity of autonomous or highly functional agricultural equipments is increasing because of decrease and aging of labors for farming. The development of autonomous vehicles in an orchard is required as one of the equipments because an orchard is usually on a hill or mountain where it is very tough for farmers to work. In this research, a new design method of an unmanned ground vehicle (UGV) in an orchard is proposed by using image-based control with a central catadioptric camera. A central catadioptric camera is very effective to keep target objects in the camera field of view because of its wide area view. The effectiveness of our proposed method is confirmed by experimental results in an orchard.

Nowadays, automation techniques for agriculture are being urgent tasks. In this paper, an Unmanned Ground Vehicle (UGV) in orchard is proposed as a base platform for monitoring trees, pesticide spraying, harvesting and so on. The control system is composed by a localization method in an orchard using 2D laser range finder and a map of trees, a robust control law based on nonlinear control theory, and a path regeneration algorithm to giude the vehicle smoothly to the target path. Experimental results in an orchard using a by-wire vehicle to which the control algorithm is applied are reported.

Various control methods based on visual information have been studied for mobile robots for years. Among them, image-based control is said to have high robustness against camera calibration errors. A drawback of image-based control is that the transitional behavior of the system is difficult to predict because it is not designed in the Cartesian space but in the image plane. Especially, unfavorable transitional behavior may cause the loss of target from the sight. In this paper, a design method of the image-based stabilizing control for a nonholonomic mobile robot is proposed not to go beyond the targets by using the state transformation. The effectiveness of the proposed method is confirmed by experiments with a two-wheeled mobile robot.