Robots: finding a good match

WHEN automating any manufacturing task, the most effective process is to have the technology well- matched to said task, especially when it comes to the application of robotics.

Choosing the right industrial robot for your use requires detailed planning as well as the right approach. Often manufac turers select robots based on their ability to perform tasks humans can’t, however taking a wider and more complete look at the tasks to be performed can often add value to the produc tion chain in the long term.

Dr Paul Wong, founder and managing director of Applied Robotics, a leading robotic sup plier, says that physiological limi tations often become the stan dard of reference for manufac tures in the automation technolo gy market: looking at what humans can’t do rather than what robots can do.

Such an approach he says is limiting to the robot’s genera tional development, along with the potential maximum capacity of performance.

“When selecting the most appropriate technology to auto mate a task, it is prudent to review all available technologies for the best match with the task at hand,” Dr Wong told Manufacturers’ Monthly.

“It may be, particularly when that manufacturing task is never going to change that much and when flexibility is less impor tant, that there are non-robotic solutions that are much more efficient and cost effective.”

To avoid the potential shortfall of a ‘what humans can’t do’ atti tude, Peter Davis, from leading robot supplier, Robotic Automation, says manufacturers should seek advice from experi enced automation integrators as to which robot is most suitable for task.

According to Davis, manufac turers also need to take into account international references in their search for robots and other automation.

“Manufacturers need to be able to analyse and benchmark their current production process es against world’s best-practices in automation and only experi enced integrators can really do this,” Davis said.

Another important considera tion manufacturers should take into account is the robot’s reach or "work envelope" to ensure that it can perform the full range of motion required in the appli cation process. Axis speeds and overall cycle-time, which must be sufficient to meet or exceed the manufacturer’s existing produc tion-line speed, are also neces sary considerations.

“The robot must be able to complete the cycle of movements involved in the application in time to meet the next product or load of accumulated products coming down the line,” says Davis.

“The cycle speed will depend not only on the robot but also on the end-of-arm tool (EOAT) cho sen, for example a gripper, how long the gripper needs to engage with the product and how many products will the gripper handle at the one time.”

Despite the technical require ment of robot selection, costs remain the underlying and often the determining factor of robot choice. To keep production costs down, more manufacturers are looking to market alternatives, such as refurbished or second- hand robots.

“The market for second-hand robots demonstrates the sound investment that robotic solutions represent, especially versus a dedicated or purpose-built machine which, while they can perform as well as robotics, are not so easily redeployed or sold thereafter,” said Davis.

Dr Wong says that while web sites, such as the recently launched Robotize online used- robot marketplace, is indicative of the growing demand for the secondhand robots, there is still the question of reliability in buy ing used-goods.

“Most robotics systems buyers will want a new robot with its full warranty in their automation system, especially when the actu al robot cost might be as low as 5% to 10% of the whole system cost. In such an integrated automation system, the integra tor will warrant the entire sys tem as a whole,” said Dr Wong.

“The second hand robot mar ket is more for those who might dabble in setting up their own robot cell, but here, the robot is more than likely to languish in a store waiting for an application or because there is insufficient internal expertise to put togeth er a working robot cell.”

According to Dr Wong, the nat ural advantage for robots is that they are intrinsically flexible manipulators and can be equipped to cope with slightly unstructured environments.

However, the advantages come with limitations of cycle time and capital costs, which is arguably balanced with more efficient production line, increase production volume and higher capacity for development over many years.

Despite the added benefits of using robots in production, Dr Wong warns there are some tasks which robots will not add effi ciency to. In this regard, he says it is essential for manufactures to seek consultation with expert integrators before purchasing a robot as well as to have a clear idea of which tasks are required.

Applied Robotics 02 9737 8633, www.appliedrobotics.com.au

Robotic Automation 1300 552 333, www.ragroup.com.au