Enhancing human-robot collaboration in industrial environments via a gesture-based communication protocol.
One of the core principles behind the HR-Recycler project is to develop new ways of enhancing human-robot collaboration in industrial environments. A key requirement for establishing an efficient collaboration between humans and robots is the development of a concrete communication protocol. In particular, human workers require a fast way to communicate with the robot, as well as a mechanism to control it in case it is necessary.
An obvious choice would be to issue voice commands. However, the context of the industrial recycling plant in which the human-robot interaction will take place is noisy, and any communication protocol that relies on sound will face many problems. A communication protocol based on facial recognition is also discarded since the workers need to wear protective masks in these contexts. Using a set of buttons or a tablet to send information to the robot can be a good solution. However, these mechanisms cannot be the only channel of communication since the worker needs a fast and intuitive communication channel on which he can resort even when he is at the workbench or handling some tool.
SADAKO has built a replica of a workbench in their premises in which the gesture recognition was tested.
In order to achieve that, we have developed a non-verbal communication protocol based on gestures that will serve as an input for the robots. We have identified the following messages where gestures will be employed: start (or resume a previously paused action), pause (current action), cancel (current action), sleep (robot goes to idle mode), point (directional point to focus attention), wave (hello), no, yes.
Ismael performing the Vulcan salutation gesture that means “Live long and prosper”. Probably the most popular way to say “hi” be tween two rational agents (or at least the coolest, according to science).
To choose which gestures will represent each of the communicated messages, we need to consider two things: gestures should be easy to remember (so we do not suggest highly complex gestures) but they should not be gestures habitually used by humans. Also, gestures should be easy to remember, so human workers will not need training sessions for remembering the gestures. However, they should not be too simple or gestures that are largely employed by humans during communication to avoid situations where humans spontaneously perform those gestures, for example, while interacting with a co-worker.
Upon detection of the “hammering” action, the robot signals a blue light. This test served to illustrate that the gesture was correctly identified and received by the robot.
For the technical implementation of such a communication system, two partners of the HR-Recycler consortium have joined efforts. On one side, SADAKO has developed a gesture detection algorithm to correctly identify in real-time each of the communication gestures defined in the protocol. On the other side, IBEC has developed the concrete non-verbal communication repertoire, as well as an interaction-control module that integrates the information coming from SADAKO’s gesture recognition software and transforms it in a specific action command that is issued to the robot.
Óscar performs a “wave” gesture that is correctly identified by the gesture recognition software developed by SADAKO.
The first physical integration session between two partners of the HR-Recycler consortium took place last month at SADAKO’s premises to perform the initial tests of the gesture-based HRI communication protocol. There, a team composed by the IBEC and SADAKO groups tested the real-time detection of several of the proposed gestures. They also verified that the interaction manager was receiving the information of the identified gestures and correctly converting it in the corresponding robot commands.