Learning to Grasp from 2.5D images: a Deep Reinforcement Learning Approach

--In this paper, we propose a deep reinforcement learning (DRL) solution to the grasping problem using 2.5D images as the only source of information. In particular, we developed a simulated environment where a robot equipped with a vacuum gripper has the aim of reaching blocks with planar surfaces. These blocks can have different dimensions, shapes, position and orientation. The experiments demonstrated the effectiveness of the proposed DRL algorithm applied to grasp tasks guided by visual depth camera inputs. When using the proper policy, the proposed method estimates a robot tool configuration that reaches the object surface with negligible position and orientation errors. This is, to the best of our knowledge, the first successful attempt of using 2.5D images only as of the input of a DRL algorithm, to solve the grasping problem regressing 3D world coordinates. I. INTRODUCTION In industrial environments, manipulator robots are usually designed to solve precise and predefined tasks. However, there are situations where it may be required to generalize the behaviour of the robots due to variations of size, shape, position, and orientation of the object to grasp. In these cases, the development of solutions according to mainstream standard computer vision and robotic control approaches can be complex and may lead to customized algorithms that cannot be easily generalized to different scenarios. Deep Reinforcement Learning addresses this task by merging the reinforcement learning and the deep learning domains, approximating the policy to learn with a deep neural network.