Part singulation system benefits for robots
The push to automate an application, whether it be assembly, packaging, or palletizing continues to grow at an astronomical pace. As the price of robotics decline and the return on investment (ROI) rises, their attractiveness becomes more and more enticing for the many types of applications. More companies are starting to consider robotics for conveyor, palletizing, or packaging applications, but have run into problems with part presentation.
Many in the industrial world can probably relate to the following issues and excuses provided by robot vendors for why the customer must clean-up their process:
- Parts are "jumbled" together
- Parts are too close to one another
- Parts do not arrive at a consistent steady flow
- Parts aren’t facing the right way
- Parts aren’t centered on the conveyor
- Parts don’t have a steady state (a stable resting position without the ability to roll easily)
- Parts move around too much as the conveyor moves.
You may think, "What’s the point in automating if all of these challenges have to be overcome? Shouldn’t the robot be smart enough to locate and place the parts?" Actually, robots can be made smart enough (with the advances in bin picking and vision technology) to be able to sort through jumbled parts. However, it isn’t cheap and it can slow the throughput of the robot.
The technology has not advanced enough to keep up with the high throughput of many machines in the packaging and palletizing world. Every application has ROI and a throughput requirement it must achieve and the vast majority of application require the parts to be singulated so that robot can locate a part and orient it quickly enough to meet the throughput demanded.
What is part singulation
Part singulation is the metering of parts to a known location conveyor, pallet, fixed endstop, etc., in a repeatable fashion with space for a gripper to grab the part in a repeatable fashion.
For illustrative purposes, every part singulation system would best resemble an hourglass of sand with the sand representing the parts in an application in a hopper represented by the top half of the hourglass. The magic happens with the metering of parts onto a known location for presentation to the robot.
How are parts metered?
The answer varies and this is the hardest and most important detail of any application.
It may be as simple as creating a hole large enough to allow one spherical part through at a time, or it may require a bowl feeder or flex feeder to separate parts and allow them to be metered in a timely and efficient manner.
Brad Czecholinski, mechanical motion control applications specialist, Cross Company. This article originally appeared on Cross Company online. Cross Company is a CFE Media content partner. Edited by Emily Guenther, associate content manager, Control Engineering, CFE Media, firstname.lastname@example.org.