Error Proofing and Poka Yoke

picking parts from a bin

Prevent Errors in Lean Manufacturing Environments

Error proofing refers to preventing a process from resulting in defects by stopping mistakes at the source, rather than down the line.  

Another word for error proofing is poka-yoke (which is Japanese for avoiding inadvertent errors). Poka-yoke design is often used to avoid human error by either warning operators when they are about to make a mistake or preventing them from making a mistake at all. Poka-yoke design makes it virtually impossible for an operator to complete an action incorrectly. 

Preventing mistakes at the source can significantly improve productivity by keeping mistakes from becoming bigger problems downstream.  

Benefits of Reliable Error Proofing

smart camera inspects car door
Never Waste Value

Quality Inspection at the Source

Error-proofing takes quality control to the next level by checking for mistakes and defects before those defects can proceed to the next stage of production.  Preventing defects from proceeding from one stage of production to the next avoids wasted time and resources spent working on defective parts. 

In manual processes, such as bin picking, visual warnings clearly indicate  to operators when their actions are correct or incorrect using colored and/or animated lights. Light-guided assembly is an excellent example of using visual indication for error-proofing.

Meanwhile, in more automated processes, error proofing solutions like sensors and vision systems can be used to ensure poblems are corrected before a process can proceed.  

Banner Engineering provides sensor, vision, and light-guided solutions for error proofing to help manufacturers increase efficiency, improve quality, and reduce downtime.  Keep reading to learn more, or contact us to discuss your specific application. 

3 Common Technologies for Error Proofing

laser sensor verifies that a metal sheet is indexed on a stamping press
Sensors for Error Proofing
  • Laser measurement sensors are often a reliable solution to error-proofing applications.  
  • Laser sensors from Banner detect and measure the most challenging targets, for error-proofing solutions manufacturers can trust. 
  • For example, in metal stamping applications, it is critical to ensure that metal sheets are properly indexed on the press before stamping to avoid material waste and damage to the press die. 
  • The press cannot operate until the sensor verifies the leading edge of the material and confirms that the metal sheet is both present and properly indexed.  
ivu color sensor detects the wrong color trim on a car door
Vision for Error Proofing
  • In some applications, a vision solution can be an excellent choice for error-proofing.
  • For example, in automotive assembly, interior trim pieces are interchangeable, but vary in color, making it easy to install the wrong piece.  As assembly progresses, correcting errors becomes more difficult.
  • If an error is detected (the wrong color trim is placed), the error must be remedied before the automotive assembly can proceed to the next step. 
ivu color sensor detects the wrong color trim on a car door
A pick-to-light solution at an assembly station
Pick-to-Light for Error Proofing
  • Perhaps one of the most common error-proofing technologies in assembly processes is light-guided picking, also known as pick-to-light. 
  • Pick-to-light devices use colored LEDs to visually guide assemblers to pick the correct parts, in the right quantities, and in the proper sequence.
  • This reduces the risk of human errors and speeds up build times to ensure high quality while maximizing productivity. 

Featured Products

Q4X laser distance sensor
Q4X Series

Rugged Laser Distance Sensor

Versatile, rugged laser distance sensors offering superior performance and capable of detecting sub-millimeter changes in distance.

  • Discrete, analog (0 to 10 V or 4 to 20 mA), clear object, and IO-Link models available
  • Reliable sensing range from as close as 25 mm and as far as 610 mm
  • Detects across a variety of target colors, materials and surfaces based on distance
  • Dual teach mode (intensity + distance) is ideal for error-proofing applications and enables clear object detection with no retro-reflector required
  • Robust housing rated to IP69K with FDA-grade stainless steel
iVu color vision sensor
iVu Series

Vision Sensor

The iVu and iVu Color Image Sensors are used to monitor parts for type, size, orientation, shape, location, and color or color variations. 

  • All-in-one solution with camera, controller, lens, and light included in one package
  • Configure in minutes using Vision Manager PC software, onboard touchscreen display, or remote touchscreen
  • Inspect multiple points with a variety of grayscale or color tools
  • Compact, rugged, IP67 housing available with integrated ring lights including red, blue, green, white, infrared or UV
  • Interchangeable lenses, including C-mount, for maximum application flexibility
  • EtherNet/IP™, Modbus/TCP, PROFINET®, PCCC, and Serial RS-232
iVu color vision sensor
PTL110 pick-to-light device

PTL110 Series

Scalable, Versatile Pick-to-Light Devices

PTL110 pick-to-light devices are multifunctional indicators with options for touch button, optical sensor, and three-digit display, connected in series to create a powerful picking system. With fast response times and flexible installation options, PTL110 systems improve speed, productivity, and quality in picking, kitting and related applications.

  • Models available with optical and touch sensor capabilities.
  • Optional 3-digit alphanumeric display can be used to indicate part count or provide other instructions.
  • M12 connectors for quick and secure installation of multiple devices with no additional cables required.
  • Indicator provides fourteen colors and multiple animation functions to differentiate multiple conditions.
  • Powered by PICK-IQ™, a purpose-built, Modbus compatible serial bus protocol that uses a Common ID to reduce the typical latency that results from polling multiple devices.
  • Can be paired with the DXM700 wireless controller for deployment on carts and mobile picking stations.

See More Error-Proofing Applications