Intelligent robots help minimise waste

UniSA's Centre for Advanced Manufacturing Research (CAMR), in collaboration with industry partner Dematec, has developed a novel automated manufacturing process by introducing the zero waste management principle.

Previously, Kilkee Stonewares produced furniture with a sandstone finish using a manual process in which operators sprayed a mixture of slurry made from polymers and other ingredients pumped through hoses held over a mould. Added to the slurry was fibreglass dispensed in lengths to create a matrix of fibres for increased strength.

This manual production process resulted in non-uniform thickness, quality control issues and significant wastage, according to CAMR's operations and business development manager, Evangelos Lambrinos.

"Every year Kilkee would dispose of about $200,000 worth of material waste and a significant stockpile of poor quality product due to the manual production process. Twice a year the company had to undertake a big clean-up and dump about a half metre build-up of overspray waste," Lambrinos said.

Lambrinos worked with CAMR researchers to develop an intelligent flexible robotic manufacturing cell, which replaced Kilkee's traditional manufacturing process with a modernised clean manufacturing environment, a major step up in production practice.

"The robot sprays the slurry from 90° above a mould placed on a mobile trolley, spraying into a shape that matches the mould, working from the outer edges to the centre at an even speed for uniform thickness, and no slurry hits the floor. The robot has a boom arm like an elbow that can extend to all areas, with pneumatics to stabilise its movement.

"We added mobile trolleys for the moulds and radio frequency tags to identify mould type and shape. An operator uses a computer to direct the robot, which can be reprogrammed for any shape mould. Once sprayed, an operator compacts the slurry in the mould using a trowel to exclude air. Left to cure overnight, the mould is then rolled to an area where it is removed, cleaned and returned for reuse," Lambrinos said.

In the manual process, moulds were carried into position, slurry was added and the moulds were then carried to another area for curing, which involved heavy lifting.

"Our automated system eliminates a lot of health issues associated with manual handling, product being sprayed in the air, and working in air that is polluted with dust and moisture. It also means that quality is assured and the footprint is much reduced in terms of space required on the factory floor.

"The most significant benefit has been lower manufacturing costs and an increase in throughput, with shorter manufacturing cycle times reducing the demand on energy use and labour requirements. This equates to more than $200,000 in savings per annum per shift," Lambrinos said.