In order to improve processing efficiency and product quality, in order to cope with the increasingly fierce market competition, engineers engaged in manufacturing, warehousing and distribution are constantly looking for a more powerful and widely used Pick-to-Light system.

Sensors are one of the key components of such systems, and its advances have helped to meet these needs. With the development of new electronic components, indicator covers and network interface functions with sensors, the light picking system can make more contributions in more fields. The resulting quality improvement significantly reduces the costs of scrap, rework and recalls, helping many companies reduce the rate of defective products, which in turn reduces the risk of penalties or lost business.

What is the light picking system:

The lamp picking sensor is used in conjunction with the control system to guide the assembly operator or warehouse personnel to step through a set of operations in a predetermined sequence. Operators often need to pick up parts from a row of racks to ensure that the equipment is properly assembled or that the order is properly fulfilled.

The light picking sensor is usually equipped with an indicator light to indicate the correct part location to the operator. The sensor is connected to a PLC that has the correct picking order. The PLC opens the sensor on the correct location and then waits for the sensor to signal that the correct part has been picked. Upon receipt of this signal, the PLC will turn on the next indicator in sequence.

Some light picking sensors also provide an audible and visual indication that alerts the operator when picking up parts from the wrong location. The indicator light may change color and/or flash.

Application areas of the light picking technology:

Typical applications for light picking technology include automotive, home appliance or electronic assembly lines. In automotive assembly plants, there is limited space for parts to be placed and they need to be delivered in order. Manufacturers continue to build logistics areas where they can pick up product components in advance and then supply them to the assembly line in the correct order.

When manufacturers set up new plants in developing markets, the light picking system is very helpful in training inexperienced workers and ensuring that product quality remains stable. It is also an ideal choice for flexible production operations that require workers to intersperse between jobs.

In car manufacturers that produce cars for many countries, cars sold in countries need to be accompanied by user manuals and labels written in the local language. It is impossible for the operator to be proficient in each language, and thus work errors may occur. With the light picking system, these parts are supplied from the logistics area to the assembly line in the correct order.

In the warehousing and distribution center, there are two main applications for the light picking system.

A typical application is for the operator to carry a list of items to and from a large number of locations and pick up parts from them. The light picking sensor can quickly direct the operator to the correct location in a reasonable order.

Another application is to use sensors to tell the operator where to place the item. When the white storage and retrieval system brings the selected location to the work area, the sensor can be used to indicate which location to place the item on.

Advantages of the lamp picking and error proofing system:

Reduce or eliminate errors: Since the system indicates a reasonable order to the operator, the probability of an error is minimal. Picking equipment by lamp is usually equipped with sensors or buttons, and the PLC will wait for the operator to use the sensor or button to confirm that the correct part has been picked. In general, the process will continue only after receiving the confirmation signal.

Increased productivity: With a light picking system for large assembly or part storage, the indicator light allows the operator to quickly and easily find the right location, significantly reducing the picking process cycle and increasing this.

Select a location to fulfill the order

Purpose: Guide the worker to pick the next item in the order and confirm the picking operation.

Description: In a warehouse, a one-piece photoelectric array type light picking sensor is mounted on the shelf above each box of books. The worker takes out a specified number of books from the lit box under the pick-up indicator light to fulfill the order. The built-in photoelectric confirmation sensor detects the worker's hand in the carton to confirm that the correct book has been taken.

Small part picking confirmation

Purpose: Indicates which part is picked for assembly and confirms that the picking operation has completed.

Note: A light picking sensor with a built-in photoelectric confirmation button is installed at each location of the assembly station. The process controller illuminates the picking indicator on the location that the worker should pick next in order. After removing the part, the worker places his hand on the built-in photoelectric confirmation button and turns off the picking indicator to indicate that the correct part has been removed.

Development history and trends of light picking technology:

The original light picking sensor consisted of a light bulb and a number of separate verification sensors. With the development of electronic circuitry such as circuit miniaturization, ASIC development, low-cost microprocessors and embedded firmware in sensors, pick-up indicators and verification sensors can be integrated into a single-light pick-up sensor.

These new sensors initially use an array of transmit/receive optoelectronic arrays that cover a wide range of sizes. Although such a light picking sensor can be applied to many new fields, it is sometimes difficult to see its indicator light from various angles.

With the popularity and heavy use of light picking sensors, cost reduction, ease of use and installation are becoming increasingly important. In addition, the need to reduce the size of the sensor, make the picking indicator lighter and brighter, and color distinctions have emerged.

The light picking sensor of different indicator covers increases the size of the picking indicator and can be seen from all directions. In addition, these indicator covers are available in a variety of mounting styles and sensor sizes. These improvements, combined with reduced costs, allow manufacturers to equip more machines with light picking sensors. As the use of light picking sensors continues to increase, manufacturers are increasingly demanding compatibility with wired and wireless bus networks.

The types of sensors used in different application areas depend on customer needs. For the case where only one part needs to be picked up at each location, many manufacturers prefer to use a light picking sensor with a built-in automatic confirmation sensor. In the case of workers having to pick up multiple parts from a single location for assembly, many customers use a light picking sensor with a built-in manual confirmation button.