Slip Information Detection And Motion Monitoring Technology Of Deformable Object Grasp

Deformable object grasp and rigid object grasp are quite different and the de-formable object grasp also has a significant impact on life and production(e.g.,deformable object manipulation of medical rehabilitation and surgery assistant robot).But the re-search on deformable object grasp and motion monitoring are still undeveloped do-mains.Efficient and reliable slip sensor and motion monitoring play critical roles in grasp object.This paper provides a new method for slip detection based on video pro-cessing,which can offer multidimensional sensing information and it is applicable for gripping deformable objects.And an efficient motion monitoring method based on slip sensor is also present.The macro cameras mounted inside the gripper can capture the dynamic slip and distortion of the object.The features of interest points,detected by the SURF algorithm in subsequent frames,are used to identify the properties of object and calculate the object's changes.To determine the object's slippage,nine detecting windows in the camera view can detect nine tracks of the slippage.Besides,the object's distortion and direction of tangential force on the surface can be determined from these tracks,which helps to the estimation of the object's damage.Experiments on homogeneous and textured materials show that this method can detect the object's slippage accurately,and meanwhile provides the tracks of the slip-page,distortion information and the force situation.Furthermore,tests for comparison were carried out and the results show that this sensor has a high accuracy in detecting slippage and distortion and the error is acceptable,which has an significant impact in deformable object grasp.With a better function in detecting slip,the proposed slip sensor can be applied in motion monitoring of the object in the grasp process.Robots grasp objects in our daily life and move the objects from a place to another,however,in this operation,the collision with the environment and the failure of grasp due to wrong calculation or detecting error can't be inevitable.It proves that the slip detection and motion monitoring are vital for stable grasp.In this paper,further,based on slip detection sensor,motion monitoring of the in-handed object are studied.The change of position can be detected using the slip sensor based on video processing.With three slip sensors mounted in the grasper fingers,the in-handed object's mo-tion change in the 3D space can be recorded.Using the record of object's motion change,the rotation matrix and translation matrix can be generated and then the mod-el of object's motion based on time can be built.With the results of the calculation,every Euler angle can be calculated.Three slip sensors were tested with a grasper in experiment part.The object is rotated around the fixed axis and moved in a straight line.The results of the monitoring method and the output of measuring equipmen-t were compared.The comparison shew that the motion monitoring method in this paper possesses a high detecting accuracy.The methods of detecting slip and motion monitoring have a magnificent in grasp field and expand its frontier.