One innovative demonstration at the recent Drives and Controls 2016 fair, was the closer interaction of human operators and robots in the same workspace to save time and improve safety. A practical demonstration was provided using Mitsubishi Electric MELFA robots

Red carpet treatment

It involved a 15kg MELFA robot, around which proximity zones were shown using coloured carpet. Visitors could safely approach the robot, which had no physical guarding in front of it, but as they entered the ‘amber’ zone the robot would switch to a creep speed and would stop entirely should the person enter the designated ‘red carpet zone.’ If the person then withdrew, the robot would resume, initially at creep speed as the person moved out of the red zone and then at full speed as the person moved away from the amber zone.

Many operations require the operator to interact with the process, for example loading or removing components and this system speeds up that process as there is no need to spend time opening and shutting traditional guarding systems. Fully integrated automation and robotic solutions can offer significant quality and productivity benefits.

Another demonstration was based around the poka-yoke system designed to reduce error in production line tasks. Poka-yoke is a Japanese term that means “mistake-proofing”.

Poka-yoke pick to light demonstration

The aim of poka-yoke is to design the process so that mistakes caused by operator error can be detected as they occur and corrected immediately, so eliminating defects at the source. Called ‘pick to light’, a solution was built around Mitsubishi Electric’s factory automation PLC and HMI technology. The controllers and touch screen displays are used to communicate with distributed ‘Poka Yoke terminals’ that visitors interacted with using a number of light, pushbutton, lever and shutter stations distributed on an CC-Link network.

The new ‘pick to light’ solution will help manufacturers to address production errors that occur when assembly line personnel are selecting parts from inventory according to instruction.

“Our robots and the ‘Poka Yoke’ pick-to-light demonstration definitely generated the most interest on the stand,” says Chris Evans, Marketing & Operations Group Manager at the company. “The pick-to-light demonstration in particular showed how human assembly tasks could be sequenced and speeded-up by guiding operators to make accurate decisions quickly.” Mitsubishi’s new ‘pick to light’ solution will be launched later in the year.

Go here for more Mitsubishi factory automation