Document Type : Research Paper


Mechanical Engineering Department, University of Technology, Baghdad, Iraq.


The object identification properties with tactile sensing are valuable in  interaction with the environment for both humans and robots, and it is the core of sensing used for exploration and determining properties of objects that are inaccessible from visual perception. Object identification often involves with rigid mechanical grippers, tactile information and intelligent algorithms. This paper proposes a methodology for feature extraction techniques and discriminates objects for different softness using adaptive robotic grippers, which are equipped with force and angle sensors in each four fingers of an underactuated robot hand. Arduino microcontroller and the Matlab program are integrated to acquire sensor data and to control the gripping action. The neural-network method used as an intelligent classifier to distinguish between different object softness by using feature vector acquired from the force sensor measurements and actuator positions in time series response during the grasping process using only a single closure grasping. The proposed method efficiency was validated using experimental paradigms that involving three sets of model objects and everyday life objects with various shapes, stiffness, and sizes.


  • Feature vector was acquired from force and actuator sensors in time series response.
  • Arduino microcontroller and the Matlab program are integrated to acquire sensor data.
  • Neural-Network used as an intelligent classifier to distinguish the object softness.


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