Soft robots are made of soft materials and have good flexibility and infinite degrees of freedom in theory. These properties enable soft robots to work in narrow space and adapt to external environment. In this paper,...
Soft robots are made of soft materials and have good flexibility and infinite degrees of freedom in theory. These properties enable soft robots to work in narrow space and adapt to external environment. In this paper, a 2-DOF soft pneumatic actuator is introduced, with two chambers symmetrically distributed on both sides and a jamming cylinder along the axis. Fibers are used to constrain the expansion of the soft actuator. Experiments are carried out to test the performance of the soft actuator, including bending and elongation characteristics. A soft robot is designed and fabricated by connecting four soft pneumatic actuators to a 3D-printed board. The soft robotic system is then established. The pneumatic circuit is built by pumps and solenoid valves. The control system is based on the control board Arduino Mega 2560. Relay modules are used to control valves and pressure sensors are used to measure pressure in the pneumatic circuit. Experiments are conducted to test the performance of the proposed soft robot.
In this paper, a human robot shared control strategy is developed and tested on a Baxter robot. Using the proposed method, the human operator only needs to consider the motion of the end-effector of the manipulator, w...
详细信息
In this paper, a human robot shared control strategy is developed and tested on a Baxter robot. Using the proposed method, the human operator only needs to consider the motion of the end-effector of the manipulator, while the manipulator will avoid obstacle by itself without sacrificing the end effector motion performance. An improved obstacle avoidance strategy based on the joint space redundancy of the manipulator is designed. A dimension reduction method is presented to solve the over defined problem of avoiding velocity to achieve a more efficient use of the redundancy. By employment of an artificial parallel system of the teleoperate manipulator and the task switching weighting factor, the proposed control method enable the robot restoring back to the commanded pose smoothly when the obstacle is removed. By implementing the dimension reduction method, the trajectory of each joint of the manipulator can be controlled at the same time to achieve the restoring task. Thus, the proposed control method can eliminate the impact of the obstacle on the remaining task. Satisfactory experiment results demonstrate the effectiveness of the proposed methods.
Triboelectric nanogenerator (TENG) has been proved to be a promising technology for harvesting decentralized energy. However, the application fields of the traditional TENGs are limited by the high crest factor. Here ...
详细信息
To tackle with mobile robot path planning problem, we developed a novel path planning method utilized 3D grid map. Firstly we construct point cloud map using mobile robot equipped with 3D-LRF, then we transform point ...
详细信息
To reproduce the characteristics of human hand motion, this paper proposes a novel four-degree-of-freedom prosthetic hand that combines the advantages of coupled motion and self-adaptive motion. A coupled-adaptive und...
详细信息
Existing in-pipe robots have insufficient adaptability when dealing with accidents in unfamiliar pipe environments. Developing a pipe robot that can be designed and manufactured quickly is one solution. The tensegrity...
Existing in-pipe robots have insufficient adaptability when dealing with accidents in unfamiliar pipe environments. Developing a pipe robot that can be designed and manufactured quickly is one solution. The tensegrity structure is a self-stressing spatial structure formed by the interaction of rigid members and flexible cables, which has the advantages of simple structure, good flexibility, deformability, and impact resistance. Inspired by this structure, we design a novel worm-like tensegrity robot for different pipe environments, which can be manufactured rapidly at low cost. Firstly, a robotic module based on the tensegrity structure is designed inspired by the motion patterns of worm-like organisms. Then, the design process of the module is presented based on the mathematical analysis of the deformation. Finally, a prototype of the tensegrity robot is developed using simple and low-cost parts in less than an hour. To test the motion performance, load performance, and inspection capability of the tensegrity robot, we designed a series of experiments on horizontal pipes, vertical pipes, elbows, and steel pipes. Experimental results show that the worm-like tensegrity robot is simple in structure, easy to manufacture, low in cost, and good in performance.
A cable-driven hyper-redundant manipulator is especially suited for manipulations in confined spaces. In most of the existing approaches, a controller is often designed to actuate the joints by pulling the correspondi...
A cable-driven hyper-redundant manipulator is especially suited for manipulations in confined spaces. In most of the existing approaches, a controller is often designed to actuate the joints by pulling the corresponding cables without the feedback from remote sensors at the joints. The un-modeled elongations of these cables due to unknown tensions often cause a decrease in control precision. To improve the performance of such a manipulator, this paper presents an investigation where miniature potentiometers are integrated into the joints for angle feedback. Furthermore, a puller-follower controller is developed to control the three cables of a universal joint for not only closed- loop joint angle control but also cable tension preservation. Applying the Hooke's Law, the cable tension is represented by its deformation. In this way, the controller is designed to realize both the desired angles and the cable deformations, without force sensing on the cables. Finally, experiments on a single joint and multiple joints were conducted to verify the effectiveness of this proposed controller.
This paper proposes a vision-based Semantic Unscented FastSLAM (UFastSLAM) algorithm for mobile robot combing the semantic relationship and the unscented FastSLAM. The landmarks are detected by a binocular vision, and...
详细信息
This paper proposes a vision-based Semantic Unscented FastSLAM (UFastSLAM) algorithm for mobile robot combing the semantic relationship and the unscented FastSLAM. The landmarks are detected by a binocular vision, and the semantic observation model can be created by transforming the semantic relationships into the semantic metric map. Semantic Unscented FastSLAM can be used to update the localization of the landmarks and robot pose even when the encoders inherits large accummative errors that may not be corrected by the loop closure detection of the vision system Experiments have been carried out to demonstrate that the Semantic Unscented FastSLAM algorithm can achieve much better performance in indoor autonomous survalience than Unscented FastSLAM.
Needle-based procedures, such as biopsy and percutaneous tumor ablation, highly depend on the accuracy of needle placement. The accuracy is significantly affected by the needle-tissue interaction no matter what needle...
详细信息
ISBN:
(数字)9781728173955
ISBN:
(纸本)9781728173962
Needle-based procedures, such as biopsy and percutaneous tumor ablation, highly depend on the accuracy of needle placement. The accuracy is significantly affected by the needle-tissue interaction no matter what needles (straight or steerable) are used. Due to the unknown tissue mechanics, it is challenging to achieve high accuracy in practice. This paper hence proposes a needle design with an articulated tip for increased steerability and improved needle path consistency. Due to the passive needle tip articulation, tissue mechanics always plays a dominant role such that the needle creates similar paths with approximately piece-wise constant curvature in different tissues. Kinematics model for the proposed needle is presented. The algorithms of path planning and needle tip pose estimation under external imaging modality are developed. Experimental verifications were conducted to demonstrate the needle's steerability as well as the target-reaching capability with obstacles avoidance.
暂无评论