This paper presents an approach for sonar feature map building. The approach is composed of extracting features at the data-level fusion stage and fusing the extracted features with the registered features in the map at the feature-level fusion stage. A data-level fusion model, termed three measurements association model (TMAM), has been developed for associating three measurements with a line or a point feature. By use of TMAM, different sets of measurements obtained from a single sonar sensor at consecutive steps are associated with the line and point features. Subsequently, the parameters of the identified features are estimated by use of the iterated least square estimation method. Finally, when a feature is extracted, a simple feature-level fusion strategy is used to update the map. The proposed approach has been tested both in simulation and on real data.

High-voltage power transmission line inspection robot must plan its behavior to detect the obstacles from the complex background according to their types when it is crawling along the power transmission line in order to negotiate reliably. In most cases, robot fulfills the task by its vision system. However, motion blur due to camera motion caused by wind or other unknown causes can significantly degrade the quality of the image acquired. This is a typical kind of the so called image restoration problem, which is a hard problem since no prior knowledge of the motion is available. For this purpose, a novel approach for image restoration is proposed. The restoration procedure consists of two stages: estimation of blur function parameters and reconstruction of images. Image degradation model is proposed first to identify blur function parameters, then a recurrent neural network is used to restore the blurred image. Experiments on real blurred images on power transmission line prove the feasibility and reliability of this algorithm. Our experiments show that the restoration procedure consumes only small amount of computation time.

Inspection robot must plan its behavior to detect the obstacles from the complex background according to their types when it is crawling along the power transmission line in order to negotiate reliably. However, in most instances, detecting the obstacles from the complex background is a hard task. For this purpose, a novel and fast visual obstacle recognition algorithm is designed based on the structure of the 220 KV power transmission line. Basic principle and architecture of the algorithm are given. By this approach, three typical obstacles on the power transmission line such as insulator strings, counterweights and suspension clamps can be recognized with high accuracy. Experiments in the real power transmission line show its effectiveness. This method can contribute to the process of the mobile robot negotiating obstacles