A casting manipulator is a robot that launches a payload as a projectile then alters the ballistic trajectory by pulling on an attached tether. Prior work in casting manipulation has focused on applying impulses through the tether to place the payload at a specific location and then retract it. In the spirit of whole-body and whole-arm manipulation, we propose that the tether itself can be used to act on the environment, rather than serving only as a means of directing the projectile. As a first step in this direction, we consider the case of throwing an end-weighted line to wrap a target above and away from the launch point. We explore the necessary conditions for successfully wrapping a target, including the various types of wrapping and the conditions required to make these wraps.

Large debris created after natural disasters restrict access to inner parts of affected regions and slows down disaster relief operations. Power shovels are often used to clear wreckage but the process can take a lot of time. Moreover, it is dangerous to involve human workers in such conditions due to loose debris collapsing and causing severe damage. To speedup access to inner areas, instead of removing obstacles, they can be surmounted with the assistance of a carefully maneuvered power shovel arm. In this paper, an autonomous obstacle surmounting technique for an unmanned power shovel is proposed. Out of different sequences, the one that optimizes the total energy consumption is selected as the best candidate for surmounting a given obstacle by dynamic simulations. The experiments conducted using a miniaturized power shovel show the effectiveness of the proposed method.

This paper presents a high-speed transportation of capsule by launch. One of the main issues for the transportation is how to decelerate the capsule during its flight to avoid a large landing impact. In order to stop the capsule temporally in the air just before its landing, we propose a flight control method by multidirectional tension of wires. Since the capsule is connected with both auxiliary weights and reel system via wires, it can be geometrically constrained not to move by multiple pull of the wires. We develop the motion planner which makes the capsule reach the target at the desired speed, and control algorithm for it. The proposed method is applied to the soft landing of the capsule. The effectiveness of the proposed method is verified through the experiment.

Supposing a space mission of setting monitoring devices at suitable positions on the moon, we discuss how to apply a casting manipulation to the mission. This paper addresses a mechanism of a casting manipulator system and control method to launch a penetrator to the desired position. First, we discuss launching methods, and focus on a method by using rotation of a boom. We then propose the mechanism that keeps a posture of the penetrator equipped at the tip of the boom constant for the absolute coordinate system during its rotation. This mechanism prevents the wire which connects the penetrator and the robot's base from winding the boom. Analyzing a position error of landing point caused by delay of releasing the penetrator, we propose the motion control of the boom to reduce the error. Finally, we develop the system and verify the effectiveness of the proposed method through experiment.

This paper deals with the practical problem as to how a humanoid robot opens a door in an office environment. Among the several tasks for the door opening, we focus on the recognition of a door and grasping its knob and propose a systematic touch scheme that combines the visual and touch data to grasp a knob safely and robustly. The visual recognition of a door and its knob is done by feature matching by a feature classifier and a segmentation method with minor assumptions about a knob, respectively. The position of a knob from the visual recognition is refined by the proposed touch scheme where a robot touches a knob several times with a hand equipped with a force-torque sensor. We realize that in the on-line experiment, a robot recognizes a door and its knob, and grasps the knob and partially opens the door.

This paper deals with the practical problem of how a humanoid robot recognizes a door and its knob in an office environment. This is the initial work where a humanoid robot recognizes, approaches, and opens a door. We propose an integrated solution for visual recognition of a door and its knob with minor constraints. In our approach, the door recognition is transformed into the classification problem of feature points, which can be done quickly enough to conduct it on-line. The knob is extracted by a segmentation method and a few thresholds: blob size, blob ratio, and the distance from the floor. We show in the experiment that our humanoid robot can recognize a door and its knob reliably and quickly.

We have been developing a casting manipulator that includes a flexible light wire in the link mechanism to enlarge the workspace of the manipulator. In this paper we focus on the motion of collecting an object via casting manipulation. We propose a method of moving the object in the air by coordinating the motions of swinging the arm and winding the wire. Then, we develop a mechanical device that changes the apparent elasticity of the wire to transmit force to the object effectively. We also develop the motion generator that provides the optimal collect motion. We confirm the effectiveness of the proposed method through simulations. Finally, we conduct experiments using casting manipulator hardware and realize the quick motion of collecting the object.

There are many kinds of large, heavy objects, or objects with geometrical constraints in our daily life, but non-fixed robots such as humanoid robots are still not able to manipulate them sufficiently well. In this paper we focus on a swing door as a heavy object with geometrical constraints, and present a method for the humanoid robots to open it by using impulsive forces. We first discuss on momentum transfer from the robot to the door. Then we propose a method of generating a whole body motion to impact on the door. We analyze the dynamic model of the door, and we confirm the validity of our method through simulation. At last, we realize a motion of the robot opening a swing door quickly by the method in experiment with the HRP-2 robot hardware.

A motion control method of lifting a heavy object up to a higher position with humanoid robots is developed. The key issue of lifting motion is how to reduce the load on humanoid arms in which low-power actuators are implemented. The use of singular postures of arms is well-known to avoid actuator saturation of the arms. By combining two different kinds of humanoid motions such as accelerating an object upward and sliding the body into under the object, we propose a method that enables to transit one singular posture of arms to another while lifting the object. Simulation results show the effectiveness of the proposed method for reducing the load on the arms. We realize a motion of lifting a heavy object dynamically with the humanoid robot HRP-2 through experiment.

We have developed a casting manipulator that includes a flexible light string in the link mechanism to enlarge the workspace of the manipulator. In the casting manipulation, an end-effector is launched to its target by releasing the string connected to it, and its trajectory is controlled by the tension of the string. In this paper, we present the midair control of the end-effector. As a simple way, we propose the braking technique to apply impulsive force to the end-effector by braking the movement of the string. Examining dynamic characteristics of the string when an impulsive force applies to it, we show that the midair motion of the end-effector can be controlled by the braking technique. Then, we apply the braking technique to the multiple braking control of the trajectory. We confirm the effectiveness of the proposed method through simulations and experiments using casting manipulator hardware.

This paper describes a motion generation method for dynamic lifting by a humanoid robot. The proposed technique suggests the possibility of taking advantage of the whole body motion in order to facilitate the lifting movement. In particular, the idea is to perform a preliminary motion in order to generate a momentum which is instantaneously transferred to the object as an impulsive force. This allows the humanoid to lift up an object that could not be lifted up only by continuous force. However an impulsive force may make the humanoid unstable. Then, we propose to set the center of percussion (CoPn) of the whole system at the center of the support polygon of the humanoid when it lifts up the object. We also propose a design method of a preliminary motion of the humanoid that generates a sufficient momentum to lift up an object without any slip, tumble and hop of the whole system. The effectiveness of the proposed method is confirmed by simulation and experiment.

In this paper, we present a method to control casting manipulation by means of real-time visual feedback. Casting manipulation is a technique to deploy a robotic end-effector at large distances from the robot’s base, by throwing the end-effector and controlling its ballistic flight using forces transmitted through a light tether connected to the end-effector itself. The tether cable can also be used to retrieve the end-effector and exert forces on the robot’s environment. Previous work has shown that casting manipulation is able to catch objects at a large distance, proving it viable for applications such as sample acquisition and return, rescue, etc. In previous experiments, the position of the target object was known exactly. In this paper, we present a first attempt at closing a real-time control loop on casting manipulation using visual feedback of moving targets. As accurate planning methods developed for off-line open-loop planning cannot be used in real-time, we develop a simplified model and control algorithm, whose effectiveness is demonstrated through experiments.

In this paper, we present a method to control Kendama by casting manipulation. Casting manipulation is a technique to control an end-effector in the air by throwing the end-effector and controlling its ballistic flight using impulsive forces transmitted through a light string connected to the end-effector itself. First, we examine dynamic characteristics of a flexible string against impulsive force. We propose a method of identifying the viscoelastic model parameters of the string through free-fall experiments. Then the technique of braking the string is applied to the trajectory control with consideration of the time delay and slip of the brake. We conduct the rebound experiments by the braking technique to confirm its effectiveness. We analyse the work space where the suitable motion of end-effector for Kendama game is generated by multiple braking. Kendama game, motion of making the perforated ball impaled on the stick, is demonstrated by casting manipulator hardware.

We have been developing a casting manipulator which includes flexible string in the link mechanism to enlarge the work space of the manipulator. In the casting manipulation, a gripper is thrown to its target by releasing the string at a suitable time after generating enough motion of the gripper by swinging. In the paper we deal with the midair motion control of the gripper after throwing it for catching a target. First, we point out the necessity of controlling the gripper in midair after throwing it. Then we propose the utilization of an impulsive force applied to the gripper in the air by restricting and releasing the motion of the string. Investigating the impulsive force generation through experiments, we proposed the plural braking control of the gripper and confirmed the effectiveness of the method by simulation results.

We have been developing a casting manipulator which includes a flexible arm made out of soft material like a string in the link mechanism to enlarge the work space of the manipulator. In casting manipulation, a gripper is thrown to its target by releasing the string at a suitable time after generating enough motion of the gripper by swinging. In this paper we deal with the catching motion control of the gripper. We consider the necessity of the midair control of the gripper for catching a target. In order to enlarge the reachable area of the gripper, we propose the method of controlling the movement of the string by the brake mechanism. We confirmed the effectiveness of the proposed multiple braking control by simulation results and experimental results.

We develop a casting manipulator which includes a flexible string in the link mechanism to enlarge the work space of the manipulator. During casting manipulation the gripper is thrown to the target by releasing the string at a suitable time after generating enough motion by swinging. In this paper we deal with the posture control of the gripper after the throwing motion. First, we point out the problems of planning for throwing the gripper while considering its posture when catching. Then we propose a method of applying an impulsive force to the gripper in the air through the string by restricting the motion of the string. Investigating the characteristics of the string through experiments, we confirm the effectiveness of the impulsive force. This method was evaluated by comparing the results of numerical simulations with those of our experiments using the experimental casting manipulator hardware.

We have been developing a casting manipulator which includes a flexible string in the link mechanism to enlarge the work space of the manipulator. During casting manipulation, a gripper is thrown to its target by releasing the string at a suitable time after generating enough motion by swinging. In this paper we deal with the midair control of the gripper after throwing it. First, we consider the factors which disturb the trajectory of the gripper, and point out the necessity of modifying the trajectory after throwing the gripper. Then we propose the utilization of an impulsive force applied to the gripper in the air through the string by restricting the motion of the string. Investigating the impulsive force generation through experiments, we confirmed the effectiveness of the method which was evaluated by comparing the results of numerical simulations with those of our experiments using the experimental casting manipulator hardware.

We have been developing a casting manipulator which includes a flexible string in the link mechanism in order to enlarge the work space of the manipulator. Like the casting motion of fly fishing, the necessary motion of the gripper, which is attached at the end of the string, is generated by swinging a rigid link The gripper is thrown to the target by releasing the string at the suitable time. In this paper we deal with the basic swing motion control of the casting manipulator. We describe a method of oscillating the casting manipulator by considering it as a two-degrees-of-freedom nonholonomic system By planning a time-periodic reference for the second joint while controlling the first joint, the desired swing motion of the system can be generated. The method was evaluated by comparing the results of numerical simulation and those of experiments using the casting manipulator hardware.

We have been developing a casting manipulator which includes a flexible string in the link mechanism in order to enlarge the work space of the manipulator. Like the casting motion of fly fishing, the necessary motion of the gripper, which is attached at the end of the string, is generated by swinging a rigid link. The gripper is thrown to the target by releasing the string at the suitable time. We deal with the swing motion and throwing motion of the casting manipulation. First, we describe a method of oscillating the casting manipulator by considering it as a two degrees of freedom nonholonomic system. The method of the swing motion generation is investigated through experiments. Next we propose a method of planning of throwing the gripper considering the time delay of releasing the gripper and frictional force which disturbs the flying motion of the gripper. The evaluation by comparing the results of numerical simulation with those of experiments using the casting manipulator hardware has shown the effectiveness of the proposed methods.

We propose a new type of manipulator, a casting manipulator, which includes flexible parts, such as a string, in the link mechanism. A gripper is attached at the end of the string. In order to let the gripper reach a target, the rigid link is swung until the necessary motion of the gripper is generated. The gripper is then thrown to the target by releasing the string at the suitable time. In this paper we describe the manipulation of a casting manipulator. We present a method of oscillating a casting manipulator by considering it as a two-degrees-of-freedom nonholonomic system. First, we propose a method to swing the manipulator for casting motion, and then discuss the selection of swing motion and decision of the timing for releasing the string.