The presence of a tactile sensor is essential to hold an object and manipulate it without damage. The tactile information helps determine whether an object is stably held. If a tactile sensor is installed at wherever the robot and the object touch, the robot could interact with more objects. In this paper, a skin type slip sensor that can be attached to the surface of a robot with various curvatures is presented. A simple mechanical sensor structure enables the cut and fit of the sensor according to the curvature. The sensor uses a non-array structure and can operate even if a part of the sensor is cut off. The slip was distinguished using a simple vibration signal received from the sensor. The signal is transformed into the time-frequency domain, and the slippage was determined using an artificial neural network. The accuracy of slip detection was compared using four artificial neural network models. In addition, the strengths and weaknesses of each neural network model were analyzed according to the data used for training. As a result, the developed sensor detected slip with an average of 95.73% accuracy at various curvatures and contact points.

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Recently, research on vacuum actuators for holding and transporting objects has been actively conducted. In particular, many vacuum actuators are used to hold and transport several objects at once. However, there is a possibility that a problem of reducing vacuum efficiency may occur when several vacuum actuators are used simultaneously in the process of transporting multiple objects. The first factor is that, due to the diversity of the object’s shape, the vacuum pad of some actuators may not touch the object, so that gripping may not occur. Second, some actuators’ vacuum pad touches the object, but the pad is not completely blocked, resulting in air leakage. This paper used a spring mechanism to solve this problem and developed a vacuum gripping actuator that can block airflow into the actuator that is not used for vacuum efficiency when driving the system before the system is driven. Due to the spring inside the actuator that can play the role of passive compliance, the length can be adjusted, so even if the distance to the object is not constant, it can hold and transport several objects. Furthermore, the pretension of the spring makes it possible to block air inflow initially. We have also developed a brake system using pneumatic and tendon to hold the actuators to maintain each actuator’s length when holding and moving objects. We unified the driving method for operating both systems for simplicity by receiving pneumatic pressure from a pneumatic compressor.