Robotics boost accuracy, flexibility for automated test machines

Amber Precision Instruments augments speed and quality with 6-axis robot to replace a slow, inaccurate gantry motion subsystem. Setup time fell from 1 week to 1 day.

By Greg Hookings July 30, 2013

Robotics helped with electromagnetic compatibility (EMC) testing and compliance, needed for successful electronics design prior to releasing a product to market. Amber Precision Instruments (API), headquartered in California’s Silicon Valley, recognized it needed a faster, more precise motion control solution.

In 2006, the developer of small-scale EMC test stations used a vertical X-Y gantry motion subsystem incorporating stepper motors, worm gears, and custom-made parts. The multi-vendor design was complex to set up and program, and also was noisy and slow in operation. The mechanical design posed inherent challenges to wiring and final assembly, and the resulting system saw limits to accuracy, reliability, and performance. Although API’s proprietary measurement software provided a powerful toolset, the mechanical system was not optimized and would not accommodate anticipated technical growth requirements, including TACT (turn around cycle time) and DUT (device under test) sampling resolution.

Accuracy wanted

Amber Precision Instruments is a private corporation that manufactures EMI (electromagnetic interference) and ESD (electrostatic discharge) scanners to help electronics suppliers comply with EMC regulations and directives. Samsung, LG, and Intel are among some of API’s Tier 1 customers that use these scanner systems. When API began researching methods to improve machine accuracy and reliability in late 2009, the engineering team turned to robots. The cost savings from reduced installation and programming times would help offset the upfront cost of the robots as a sub-system. Furthermore, streamlined multi-axis control facilitates a more accurate method of delivering data to customers.

Robot replaces gantry system

In early 2010, API discovered an industrial robot offering that has technical sales support and field engineering services in North America. API purchased a vertically articulated 6-axis robot for its SmartZap ESD test station. This stand-alone robot provided an opportunity to test a solution in lieu of the complicated X-Y gantry system. The fully automated SmartZap uses 5 cameras to define the geometry of a DUT (typically a PCB, mobile phone, or tablet) allowing software to calculate 3D points for testing. The robot, equipped with TCP/IP communication, then receives discrete move commands from the software to position an ESD gun or finger emulator to specific locations on the DUT. The end result is a comprehensive data map with localized ESD characterization information.

1 day, not 1 week

Using the robot technology improved accuracy and repeatability and helped reduce machine setup time from 1 week to 1 day. Partnering with the robotic company also helped improve API’s credibility with current and prospective clients by offering an attractive solution, high-quality product, and 2-year warranty. The automation vendor has service and support centers located globally. Giorgi Muchaidze, manager of system integration at API, commented that help from the robotic and automation provider enabled the company to “surpass our competition in performance and quality.”

According to Jin Min, director of operations at API, industrial automation will play a larger role for EMC testing in the future, and API is optimistic to engineer even more powerful systems that use this technology.

Seeing the value from the first 6-axis robot, API followed suit with two models of 4-axis SCARA (selective compliant assembly robot arm) robots for its SmartScan system. The SmartScan system is available for ESD and EMI.

Solution savings summary

The EMC test machine with the 6-axis robot:

  • Improved accuracy and repeatability
  • Reduced setup time
  • Resulted in higher quality
  • Improved customer satisfaction
  • Improved reliability.

Products inside – Online extra

Mitsubishi Electric Automation’s technical sales support and field engineering services in North America helped in API’s decision to purchase the vertically articulated 6-axis RV-3SD for its SmartZap ESD test station. Partnering with Mitsubishi Electric has played a role in improving API’s credibility with current and prospective clients by offering an attractive solution, high-quality product, and 2-year warranty. Mitsubishi has automation, service, and support centers globally.

The SmartScan EMC test machine with Mitsubishi Electric’s 4-axis RH-6SDH SCARA robot is one of Amber Precision Instruments’s most popular products. Seeing the value from the first 6-axis robot, API selected two models of 4-axis SCARA (selective compliant assembly robot arm) robots from Mitsubishi for its SmartScan system. 

– Greg Hookings, marketing communications manager, Mitsubishi Electric Automation Inc. Edited by Mark T. Hoske, content manager, CFE Media, Control Engineering, mhoske@cfemedia.com.

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