Design and control of a novel 3D casting manipulator

Abstract

This paper focuses on casting manipulation and presents an innovative mechanism that allows objects placed in a three-dimensional space to be reached with a relatively small robot. Casting manipulation is a technique by which a robotic end-effector is thrown and its ballistic flight is controlled through a tether cable so as to reach a target object. Previous work presented a solution that is viable only when the position of the target object is perfectly known or aligned with the throwing plane. Our work extends the technique by use of a novel mechanical design of the arm, and a suitable control scheme for the flight of the end-effector, which makes it applicable for objects placed at generic positions in a threedimensional environment. Effectiveness of the casting robot was shown during the first ESA Lunar Robotics Challenge, where our team came in the second place.

Rough Terrain Traveling Method Using an Elastic Telescopic Arm and a Tether

“…First, compared with the previous method using tethers [1]- [3], the proposed method allows the moving vehicle equipped with an ETA to move on rough terrain without using multiple robots. Second, compared to the method of attaching the gripper to a random sturdy object in the external environment by casting [4] [5], the hook can be quasi-statically fixed to the external environment by precisely controlling the position of the arm Fig. 4.…”

“…towing with the tether attached to the gripper. Studies on the casting manipulation of grippers [4] [5] fix the tether to the external environment by casting. However, these methods have problems such as uncertainty, hazard of casting of the grippers, and difficulty in manufacturing a driving mechanism with a wide range of reduction ratios that can handle both winding and casting.…”

Interacting with Obstacles Using a Bio-Inspired, Flexible, Underactuated Multilink Manipulator

“…Mochiyama cast an end-effector connected by a flexible elastic rope to the ground using a pneumatic system, and aimed it at a desired target location [17]. Fagiolini developed a simple two-DOF system that spins an end-effector at a high velocity, and then releases and casts it to a target [18]. In all the above-mentioned works, the authors model the system using ODEs by describing the deformable object as a set of links.…”

Modeling and Control of a Cable-Suspended Sling-Like Parallel Robot for Throwing Operations

“…Later, the same authors proposed in [33] the idea of controlling the EE motion in midair, by controlling the tension of the string to which the EE is attached. In [34], this approach was extended to a 3-DoF spatial parallel robot; later on, in [35], a casting robot was proposed using a serial robot arm mounted on a mobile robot. In [36], a robotic arm launched a probe to a target location while the probe orientation was kept fixed during the launch motion.…”

“…Throwing robots were also applied for entertainment purposes [19,25], for instance in juggling [17], therefore we also envision an application for our work to a robotic game-playing platform: the robot could be used to launch a ball towards players and catch it back from them, taking advantage of the large DW of CSPRs to move across a playing field. Another interesting application would be in hostile environments, such as space [34,35] or disaster-stricken areas [33,36,37], for example to launch a grappling device [37] or a penetrator [36] (with an attached wire) towards a target point in order to retrieve samples or to attach a tether. Finally, we also suggest that our robot could be used in a casting configuration for fly-fishing purposes, by throwing a hook in a body of water.…”