Abstract: It is desirable to have a mobile robot that can move and perform various tasks over irregular terrain. However, conventional systems are not reliable or sufficiently adaptable for practical application. A traditional method for climbing stairs is to use grouser-attached tires or tracks that can grip the edges of the stairs. However, with this method, usually only one grouser on each side of the vehicle grips the stairs because the spacing between the grousers does not necessarily coincide with the distance between the steps. In the present paper, a new stair-climbing crawler with high gripping force on the stairs is developed. Powder-filled blocks are attached to the face of the tracks so that the belt can change shape to match the edge of the steps. A large friction force is therefore obtained due to the soft deformation of the blocks at every point along the belt. The results from these stair-climbing experiments prove that the newly developed crawler with powder-filled belts is more reliable than other experimental crawlers when ascending and descending stairs. The current crawler, with powder-filled belts, can carry heavy loads. The maximum payload capacity is approximately 60 kg when ascending stairs at an angle of 30°. Furthermore, the proposed crawler can change direction when climbing stairs or obstacles, which improves the turning efficiency of the crawler.