Human-Robot Interaction Based on a Sensitive Bumper Skin

Abstract

In order to enable robots to work in close contact with humans or in environments with unknown obstacles, new reactive control strategies based on sensitive bumper skins are proposed. The aim of this work is to provide a robot with contact and force control based strategies that make it dependable, safe and with foreseeable behaviours.The sensory skin is composed of rigid-bumpers provided with deformation sensors incorporated in a flexible substrate. This solution is a compromise between a simple bumper skin and current array-based robot skins, with better potential performances but, more costly and with usability problems. Such sensitive bumpers cover all moveable links of the robot allowing the detection of collisions, measuring the force involved and locating the point of contact with reasonable precision and cost.Index Terms -Human-robot interaction, safe robots, robot skin, compliant behaviour.

A survey of Tactile Human–Robot Interactions

“…A skin of rigid bump sensors developed by Frigola et al [12] covers all movable links of an industrial robot arm, with the stated aim of exploiting both the robustness of hard-shell skins and the detection sensitivity of soft array-based skins. The skin consists of deformation sensors in rubber (3-4 per panel), placed under a rigid metal sheet covering (Fig.…”

“…An 8-DoF manipulator arm responds evasively to touch for human-obstacle avoidance during movement execution [42]. The redundant degrees of freedom in an industrial arm are exploited to maintain end effector position under external disturbances caused by a human, for evasive and safety measures [12,34]. The small entertainment humanoid SDR-4X II performs pinch detection at major joints to avoid trapping or injuring the detected (possibly human) object.…”

“…the human's) state. 12 In Behavior selection the robot interprets tactile feedback in order to select between existing robot behaviors. 13 In Behavior execution human contact is an expected part of robot operation, for example the robot being stroked by a patient as a part of animal-surrogate therapy.…”

“…In Behavior guidance the robot interprets the detected contact as a cue to guide behavior execution, for example the physical guidance of tooltip position. 14 In Behavior development, the robot responds 12 The use of contact information for State classification often serves as a precursor for its use within Behavior Guidance or Behavior Execution. 13 Behavior Selection works to date select from a discrete set of high-level behaviors, but future work could select from an infinite set of lower-level behaviors or actions.…”

Safety provisions for human/robot interactions using stochastic discrete abstractions

“…A different alternative is the massive introduction of sensors on the robot whose purpose is to halt the system as soon as a potential danger is detected. This can be done by proximity sensors [4] or a special sensorized skin that detects dangerous force patterns on the surface of the robot arm [5]. While this approach can be a valid replacement for fencing off the working space of the robot, its application has still a big impact on the productivity of the site.…”