Purpose: The installation of industrial robots requires security barriers, a costly, time-consuming exercise. Collaborative robots may offer a solution; however, these systems only comply with safety standards if operating at reduced speeds. The purpose of this paper is to describe the development and implementation of a novel security system that allows human–robot coexistence while permitting the robot to execute much of its task at nominal speed. Design/methodology/approach: The security system is defined by three modes: a nominal mode, a coexistence mode and a gravity compensation mode. Mode transition is triggered by three lasers, two of which are mechanically linked to the robot. These scanners create a dynamic envelope around the robot and allow the detection of operator presence or environmental changes. To avoid velocity discontinuities between transitions, the authors propose a novel time scaling method. Findings: The paper describes the system’s mechanical, software and control architecture. The system is demonstrated experimentally on a collaborative robot and is compared with the performance of a state-of-art security system. Both a qualitative and quantitative analysis of the new system is carried out. Practical implications: The mode transition method is easily implemented, requires little computing power and leaves the trajectories unchanged. As velocity discontinuities are avoided, motor wear is reduced. The execution time is substantially less than a commercial alternative. These advantages can lead to economic benefits in high-volume manufacturing environments. Originality/value: This paper proposes a novel system that is based on industrial material but can generate dynamic safety zones for a collaborative robot.

In this paper, a force/vision control strategy is proposed in order to separate soft deformable materials using cooperative robots. The separation is performed by repeating a series of cuts, called passages, along a curved trajectory. The vision control is used to locally update the robot trajectory in response to both on-line deformations and off-line modeling errors. The force controller is used to ensure that the cut is performed without global deformation or damage to the surrounding area. The second robot is used to facilitate the cutting by applying external forces to the object. The control scheme is validated experimentally by cutting soft foam material.

Cable-Driven Parallel Robots (CDPRs) have several advantages over conventional parallel manipulators most notably a large workspace. CDPRs whose workspace can be further increased by modification of the geometric architecture are known as Reconfigurable Cable Driven Parallel Robots(RCDPRs). A novel concept of RCDPRs, known as Mobile CDPR (MCDPR) that consists of a CDPR carried by multiple mobile bases, is studied in this paper. The system is capable of autonomously navigating to a desired location then deploying to a standard CDPR. In this paper, we analyze the Static equilibrium (SE) of the mobile bases when the system is fully deployed. In contrast to classical CDPRs we show that the workspace of the MCDPR depends, not only on the tension limits, but on the SE constraints as well. We demonstrate how to construct the Available Wrench Set (AWS) for a planar MCDPR wih a point-mass end-effector using both the convex hull and Hyperplane shifting methods. The obtained results are validated in simulation and on an experimental platform consisting of two mobile bases and a CDPR with four cables.

In this paper, the modeling, simulation and control of a robotic meat cutting cell is described. A dual-arm system is used in the separation task, one arm cuts the meat along a deformable guide line while the second arm graps and pulls the meat to further increase the opening of the valley. The steps taken to model the cell in order to ensure a realistic interaction between the robots and the flexible object are outlined. A control scheme, using an external vision and force sensors, is proposed that copes with on-line object deformation. The proposed control scheme is validated using the simulator environment.