A Safety-Aware Kinodynamic Architecture for Human-Robot Collaboration

Abstract

The new paradigm of human-robot collaboration has led to the creation of shared work environments in which humans and robots work in close contact with each other. Consequently, the safety regulations have been updated addressing these new scenarios. The mere application of these regulations may lead to a very inefficient behavior of the robot. In order to preserve safety for the human operators and allow the robot to reach a desired configuration in a safe and efficient way, a two layers architecture for trajectory planning and scaling is proposed. The first layer calculates the nominal trajectory and continuously adapts it based on the human behavior. The second layer, which explicitly considers the safety regulations, scales the robot velocity and requests for a new trajectory if the robot speed drops. The proposed architecture is experimentally validated on a Pilz PRBT manipulator.

Online Computation of Time-Optimization-Based, Smooth and Path-Consistent Stop Trajectories for Robots

“…In order to evaluate the convergence and the complexity of our proposed methodology, we follow a numerical approach. To do so, we optimize (21) for a set of randomly generated problems, on the set of minimum jerk trajectories. Each problem is constituted by 1.…”

“…In order to achieve path consistency, the authors of [21][22][23][24][25][26] implemented different techniques inside the control loop to dynamically choose the linear scaling of the desired trajectory. Multiple safety criteria are also considered in [27] and verified online to formally ensure path-consistent fail-safe stops.…”

“…( 2), (18) and either (19) or (20). (21) We implement the presented approach using the GSplines library [38] for curve representation and the IPOPT optimizer [39] using the options in Table 1.…”

“…To test the uniqueness of the solution, we solve (21) for each problem using three different families of initial guesses given by…”

Trends of Human-Robot Collaboration in Industry Contexts: Handover, Learning, and Metrics

“…Keeping a predefined distance between the robot and the human is a safety measurement that will, in all motions, interfere with the robot's path planning. Different types of sensors and several strategies have been adopted to avoid potential collisions by jointly considering aspects of human monitoring and motion planning [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58]. When it comes to physical humanrobot interaction (pHRI), ref.…”