Design of Hybrid Cells to Facilitate Safe and Efficient Human–Robot Collaboration During Assembly Operations

Abstract

This paper presents a framework to build hybrid cells that support safe and efficient human–robot collaboration during assembly operations. Our approach allows asynchronous collaborations between human and robot. The human retrieves parts from a bin and places them in the robot's workspace, while the robot picks up the placed parts and assembles them into the product. We present the design details of the overall framework comprising three modules—plan generation, system state monitoring, and contingency handling. We describe system state monitoring and present a characterization of the part tracking algorithm. We report results from human–robot collaboration experiments using a KUKA robot and a three-dimensional (3D)-printed mockup of a simplified jet-engine assembly to illustrate our approach.

Dynamic Affect-Based Motion Planning of a Humanoid Robot for Human-Robot Collaborative Assembly in Manufacturing

“…The pHRI were expressed in terms as described below: Safety: The safety criterion included injury, accident, damage, collision, and impact that could harm the human, robot, materials, and the environment during the assembly [11,16]. The number of collisions, injuries, and damages that occurred during the assembly were the objective criteria to evaluate safety.…”

“…We developed a one human-one robot hybrid cell as shown in Figure 3 [16], where a human and a robot (Baxter,research version [42]) collaborated with each other to accomplish the selected assembly task. The robot had two arms, an infrared (IR) rangefinder sensor at the wrist, vision cameras at the head and wrists, and a face screen at the head that could be used to display its affective states, assembly instructions, and text messages if any [16,42]. As Figure 3 shows, in the hybrid cell, the parts were initially put at "A" and "C", then the parts were sequentially manipulated to "E" (a position near the human), As Figure 2 shows, in current practices in industries, these parts are stored on shelves.…”

“…We believe that the recent advancements in lightweight and low-cost flexible industrial robots, e.g., Baxter [5], Kinova [6], and KUKA [7], can be used to provide flexibility and ensure cost-effectiveness in assembly through proper collaboration between humans and robots, which can also greatly improve assembly performance in terms of productivity, quality, and safety [8]. Being motivated by the above prospects, Human-Robot Collaboration (HRC) in assembly has become an active area of research, and a significant number of contributions have been made toward HRC in assembly [9][10][11][12][13][14][15][16][17][18][19][20][21].…”

“…At present, the formation of the humanrobot hybrid cell for HRC assembly is being prioritized due to its advantages, such as convenient task allocation, easy resource mobilization, and ease of communication and supervision [11,16]. A few detached initiatives are taken for the evaluation of HRC in assembly in human-robot hybrid cells; for example, safety and efficiency are evaluated in [16], and safety and cognitive workload are analyzed in [11]. Nonetheless, the scope of the evaluation is limited, and the evaluation methods and metrics are not so appropriate.…”

Human-Robot Interaction Review: Challenges and Solutions for Modern Industrial Environments

“…-1) Simplified risk analysis based on historically occupied regions 2) Planning algorithms to perform optimal human-robot movements on shared environments 3) AR assistance for task developing or robot programming [160]- [163] [130], hybrid cells for simultaneous assembly between an operator and a robot [55], [131], [132], use of augmented reality as a support system for operators on a collaborative assembly [133], dual-arm cooperative and flexible assembly [134] and the installation of heavy and bulky components [135]. There are also support activities to assembly task as a chaotic bin-picking task for low volume assemblies [136].…”