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This paper presents a preliminary investigation on a one-degree-of-freedom programmable inertia generator. An inertia generator is a hand-held haptic device that has a programmable inertia. By moving internal masses in reaction to accelerations induced by the user, the effective intertia of the device is modified in order to render a prescribed perceived inertia. In this paper, a one-degree-of-freedom device with one internal moving mass is proposed. The dynamic modelling of the system is first presented. Then, a controller is designed to produce the appropriate motion of the internal mass in reaction to the acceleration induced by the user. A prototype is presented and experimental results are discussed.

This paper presents an intelligent assistive robot designed to help operators in lifting and moving large payloads through direct physical contact (hands-on-payload mode). The mechanical design of the robot is first presented. Although its kinematics are similar to that of a cable-suspended system, the proposed mechanism is based on articulated linkages, thereby allowing the payload to be offset from the rail support on which it is suspended. A dynamic model of the robot is then developed. It is shown that a simplified dynamic model can be obtained using geometric assumptions. Based on the simplified dynamic model, a controller is then presented that handles the physical human-robot interaction and that provides the operator with an intuitive direct control of the payload. Experimental validation on a full-scale prototype is presented in order to demonstrate the effectiveness of the proposed robot and controller.

This article presents a novel robotic assistive device for the handling of large payloads. The design of the robot is based on the application of the following fundamental mechanical principles: inertia is minimized, a parallel closed-loop cable/belt routing system is used to kinematically decouple the transmission from fixed actuators and to the end-effector, and variable static balancing is used to minimize the actuation forces required for vertical motion. As a result, the device requires only low power, thereby improving safety, and can be operated manually, even in the event of a power failure (with minimum backup power for brake release). A novel force/torque sensor is also introduced along with a control algorithm based on variable admittance that provides a very intuitive interface for physical human-robot cooperation. Finally, a full-scale prototype integrating all of the above concepts is presented.

This paper investigates the design and experimental development of planar programmable inertia generators. An inertia generator is a hand-held haptic device that has a programmable inertia. By moving internal masses in reaction to accelerations induced by the user, the effective inertia of the device is modified in order to render a prescribed inertia. In this paper, a one-degree-of-freedom device with one internal moving mass is first proposed. The corresponding dynamic model is developed and the rendering capabilities of the device are investigated. Then, a controller is designed to produce the appropriate motion of the internal mass in reaction to the acceleration induced by the user. A prototype is presented and experimental results are discussed. A mechanical architecture is then proposed for the design of a planar three-degree-of-freedom inertia generator. The corresponding dynamic model is derived, and it is shown that the generalized inertia matrix of the proposed mechanism is always of full rank. The rendering capabilities of the device are also investigated. Finally, simulation results obtained with the three-degree-of-freedom inertia generator are reported and discussed.

This paper presents an intelligent assistive robot designed to help operators in lifting and moving large payloads through direct physical contact (hands-on-payload mode). The mechanical design of the robot is first presented. Although its kinematics are similar to that of a cable-suspended system, the proposed mechanism is based on articulated linkages, thereby allowing the payload to be offset from the rail support on which it is suspended. A dynamic model of the robot is then developed. It is shown that a simplified dynamic model can be obtained using geometric assumptions. Based on the simplified dynamic model, a controller is then presented that handles the physical human-robot interaction and that provides the operator with an intuitive direct control of the payload. Experimental validation on a full-scale prototype is presented in order to demonstrate the effectiveness of the proposed robot and controller.

This paper presents a cable-suspended crane system to assist operators in moving and lifting large payloads. The main objective of this work is to develop a simple and reliable system to help operators in industry to be more productive while preventing injuries. The system is based on the development of a precise and reliable cable angle sensor and a complete dynamic model of the system. Adaptive horizontal and vertical controllers designed for direct physical human-robot interaction are then proposed. Different techniques are then proposed to estimate the payload acceleration in order to increase the controller performances. Finally, experiments performed on a full-scale industrial system are presented.

This paper presents a cable-suspended crane system to assist operators in moving and lifting large payloads. The main objective of this work is to develop a simple and reliable system to help operators in industry to be more productive while preventing injuries. The system is based on the development of a precise and reliable cable angle sensor and a complete dynamic model of the system. Adaptive horizontal and vertical controllers designed for direct physical human-robot interaction are then proposed. Different techniques are then proposed to estimate the payload acceleration in order to increase the controller performances. Finally, experiments performed on a full-scale industrial system are presented.