In this paper, we proposed a 3D printed soft robot gripper with modular design for lunch box packing. The gripper consists of a rigid base and three soft fingers. A snap-lock mechanism was designed for easy attach-detach assembly of the gripper without using screws. All components were 3D printed and the soft finger structure is based on the principle of fluidic elastomer actuator. Three finger designs, and soft gripper grasping and lifting deformable objects were investigated through finite element (FE) analysis and experiments. Results suggested that different finger designs yielded different curvature along the finger and generated different stress distribution once pressurized. The proposed gripper could grasp and lift objects with variable shapes and softnesses.

This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor’s main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human–robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery) robot, and includes its design, fabrication, and evaluation tests.

In order to determine the cause of and to treat an abnormal heart rhythm, electrophysiological studies and ablation procedures of the heart sensorized catheters are required. During catheterization, force sensors at the tip of the catheter are essential to provide quantitative information on the interacting force between the catheter tip and the heart tissue. In this paper, we are proposing a small sized, robust, and low-cost three-axis force sensor for the catheter tip. The miniaturized force sensor uses the fiber-optic technology (small sized multi-cores optical fiber and a CCD camera based on image processing to read out the forces by measuring light intensity, which are modulated as a function of the applied force. In addition, image processing techniques and a Kalman filter are used to reduce the noise of the light intensity signals. In this paper, we explain the design and fabrication of our three-axis force sensor and our approach for reducing noise levels by applying a Kalman filter model, and finally discuss the calibration procedure. Moreover, we provide an assessment of the performance of the proposed sensor.

This paper describes the modeling of a soft three-axis force sensor. The sensor has a cylindrical cantilever beam made of silicone rubber that compresses and bends when normal and tangential forces are applied. The displacement of the beam's end is calculated by measuring the change of the magnetic field emitted by a permanent magnet embedded in the soft beam, at fixed points in space. Spring theory and bending theory are used to calculate the normal and tangential force components. The normal forces calculated by the proposed model and the measured values have an error less than 5% validating the analogy of the sensor to a soft cantilever beam under compression and bending. The proposed mathematical model is simple and faster than a finite-element model, and accurately represents the non-linear behavior of the sensor's physical effects to applied loads.

Flexible soft and stiffness-controllable surgical manipulators enhance the manoeuvrability of surgical tools during Minimally Invasive Surgery (MIS), as opposed to conventional rigid laparoscopic instruments. These flexible and soft robotic systems allow bending around organs, navigating through complex anatomical pathways inside the human body and interacting inherently safe with its soft environment. Shape sensing in such systems is a challenge and one essential requirement for precise position feedback control of soft robots. This paper builds on our previous work integrating multiple optical fibres into a soft manipulator to estimate the robot's pose using light intensity modulation. Here, we present an enhanced version of our embedded bending/shape sensor based on electro-conductive yarn. The new system is miniaturised and able to measure bending behaviour as well as elongation. The integrated yarn material is helically wrapped around an elastic strap and protected inside a 1.5mm outer-diameter stretchable pipe. Three of these resulting stretch sensors are integrated in the periphery of a pneumatically actuated soft manipulator for direct measurement of the actuation chamber lengths. The capability of the sensing system in measuring the bending curvature and elongation of the arm is evaluated.

The following paper presents the concept of a layer jamming based soft glove for hand tremor suppression, its implementation, validation of the soft glove for hand tremor suppression and evaluation of the effect of layer jamming actuator placement. Wearable tremor suppression devices can avoid the side effects which occur due to available medical treatments, but contemporary methods are bulky and negatively affects the voluntary motions of the hand. Hence, a soft tremor suppression device can be developed to overcome the issues faced in contemporary wearable devices. A hand tremor suppression device using layer jamming was proposed in the study. In this study, experimentation for the material selection for layer jamming elements, evaluation of the layer jamming element placement and validation of the soft glove were conducted to characterize and evaluate the performance of the soft glove. Layer jamming material selection was done by measuring the deflection against an applied load. The performance of the soft glove was evaluated by measuring the suppression of a simulated tremor for the dorsal and palmar configurations. Performance evaluation shows a maximum tremor reduction of 78.32% in the palmar side element configuration in comparison to 38.23% in the dorsal side. Performance evaluation shows promising results in the suppression of hand tremors using the proposed soft glove and the results suggest that the palmar side element configuration can achieve higher tremor reduction comparatively.