Toolcraft Inc., a small precision machining shop in Seattle, makes parts for industries including aerospace, defense, and medical. It needed help tending its CNC machine and ultimately turned to Universal Robots A/S’s e-Series collaborative robots.
Faced with labor shortages and a demanding manufacturing task, Toolcraft assessed its alternatives and worked with an integrator to apply a UR5e cobot to its process.
Challenge
Toolcraft needed to automate a three-step task to keep up with production demands, especially when a large medical device required it to add a third shift for round-the-clock operations. Finding workers is difficult in a region with 3% unemployment.
“Nobody wants to run on third shift around here,” said Steve Wittenberg, director of operations at Toolcraft. “When you put an ad out, you’re not getting very many responses.”
The company initially looked at traditional industrial robots but realized that it would have to add costly safety infrastructure.
“If we looked at just the robot hardware alone, that appeared to be a more cost-effective solution,” Wittenberg said. “But once we started factoring in the savings on not having to erect a safety cage – and the time saved on the ease of use, avoiding a lot of complex programming – Universal Robots ended up being the right solution.”
Solution
Toolcraft discussed its need for loading a medical device part into a CNC machine for multi-threading with Rapid Design Solutions, a certified systems integrator for UR cobots.
“When we heard that the repeatability of the UR5e was down to 30 microns, we were very excited,” said Troy Ojalehto, owner of Rapid Design Solutions. “That really competes in the same space as traditional industrial robots, so that was huge for us. I have not seen other cobots handling this level of precision with multi-op parts like this, with raw stock going in and completed precision parts coming out.”
Thanks to its force-feedback feature, the UR5e is able to make the part fit tightly in the CNC fixturing. “Using the force motion with freedom in the X,Y and rotational Z axes, we can force the part in there, and wiggle it, and program that compliance very easily to enable basically a human touch with the robot,” he said.
The UR+ program, which certifies that accessories such as grippers, vision systems, and software will work with UR cobots, helped speed up integration.
“For this application, we chose a Pneu-Connect pneumatic gripper,” said Ojalehtos. “A big factor is that it’s UR+ certified, which means it works with Universal right out of the box, with all gripper software integrated directly on the UR teach pendant, eliminating the need to do any script coding.”
Results at Toolcraft
“Some of the benefits we’ve seen right off were a significant production increase,” said Wittenberg. “We were able to staff that third shift and went from producing 255 parts a week to 370 parts per week. Along with that, we’re able to finish our year’s production seven weeks sooner, thus freeing up that machine to produce parts on other jobs.”
After six months, Toolcraft saw costs decline by 23%, and it now expects a return on investment on the cobot arm at about 12 months.
“We’re going to be able to be more competitive on a lot of the long-term work that we have,” Wittenberg said.
Since the UR5e cobot only tends parts for six minutes out of a 56-minute cycle, a Toolcraft engineer added a part rinsing and cleaning station after using Universal Robots‘ online training.
“After our automation engineer took the online UR Academy, he spent a few hours with the integrator and was able to add that station to the cobot cycle with no external help otherwise,” said Wittenberg. Universal Robots’ simulator also allowed Toolcraft to program most of the additional tasks without taking the cobot offline.
In addition, the company was easily able to use Universal Robots‘ I/O interfaces to control the pneumatic fixture and door actuators. “This greatly reduces the need for CNC wiring and preserves all the CNC’s standard safety functions,” Ojalehto said.
The installation has been so successful that Toolcraft is planning to install one cobot every year. “The fact that our own automation engineer is now able to go in and troubleshoot anything that comes up is going to be key in us meeting this goal,” Wittenberg said.
Toolcraft plans to automate tending a horizontal mill next. “That’s a potential challenge because of the mills using rotary tombstones that are swapped in and out of the milling machine, which creates some difficulties with fixturing,” said Wittenberg. “But we’re confident we can solve those using a Universal Robot and some innovation in fixturing.”
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