The technical work performed since the start of the project in February 2017, concerns:
- The definition of a first Robot/Operator interaction in an OWA cell
To perform this work, we envisaged a new proposed assembly process allowed by the robotized OWA cell solution. Then to distribute tasks, and make the cobotic system (human + robot system + task + environment) usable and acceptable by human, we took into account all the necessary requirements: standards, technical, industrial with physical and cognitive ergonomics parameters. Different scenarios, but not definitive, have been pictured. We can quote a cobotic system in an assembly task with human supervisor and cobot(s) supervisee or a cobotic system where human and robot system are coworker. The main interesting results are the capacity in the Project CORDIAL to set a versatile and dynamic platform where the operator can vary his activity being independent vis-à-vis the robot system, keeping his know-how, his power of decision while technical and industrial requirements are filled.
The risk assessment has been realized on the proposed production layout knowing it will evolve with the project advancement. It appears that the mains sources of hazards identified during non-routine operating conditions are engineering errors and human mistakes. Poor environmental conditions and human mistakes are the main sources of hazards in production conditions, both are intertwined. AeroSpline used a work method from the EN ISO 13849 standard to assess the risks and the preventive safety measures are hierarchized. The risk reduction measures are adopted at the conception phase first: energy and effort limitation of the cobotic system (NF EN 81-1), and ergonomic attention (general working conditions). Second, efforts are done in means of protection like intrusion detection system or relevant safety function in the CORDIAL workstation and the performance level associated. Third, compensatory prevention measures as slow speed or passwords should be installed. The emergency stop is a complementary measure of this first measures. Finally, actions for use must be envisaged: skill and training, preventive maintenance, indication light and Personal Protective Equipment.
- The design of the end-effector is progressing. This is the fruit of upstream work with consortium members. A benchmarking of existing equipment and similar solutions and a deeper reasoning about the end-effector architecture have been done to establish a base of discussion and opens the ways of engineering solutions.
The end effector is a multifunctional system which consists in different module to be joined together:
• The main frame of the effector is generally in single aluminum body part. Linear guides are fixed on this frame to drive the different parts of the machine.
• The different modules perform each specialized functions of the end-effector like:
Drilling – countersinking tool with lubricant and vacuum devices
Riveting plus rivet pre-feeding device
• The multi-sensors module will ensure the effector is located correctly and will control the hole aspect after drilling and the rivet aspect after fastening.
• The clamping device is an integral part of the end effector to comply with the industrial requirements, assuming contact with the parts, measuring the zero level for countersinking, holding hose to evacuate chips, etc.
The designs are guided by internal mechanical and controlling constraints, and also by light weight robot limitations such as their payload capacity. The modular approach will give the opportunity to change spindle or riveting solution if necessary. A high accuracy control system XLIM will be available on a second exchangeable device, mounted on a second robot arm.
- The specification report for the demonstration has been achieved with all elements that will be part of the assembly workshop of SAAB and requirements installation for the blind ERGO-TECH fastener which will be used have been defined.
- The Xlim team presented its effective advancements with a new effector dedicated to topology measurements of countersunk after drillings and rivets flushness after installation. The system has been mounted on one of AeroSpline UNIVERSAL ROBOTS robot arm UR10.
