ifm electronic GmbH

At its production and development facility in Tettnang on Lake Constance, ifm electronic GmbH relies on autonomous mobile transport robots to relieve the pressure on its employees and implement lean production. Six robots from Danish manufacturer Mobile Industrial Robots (MiR) keep the production lines supplied with material. A key advantage: ifm is able to program the MiR robots itself, expanding their capability with its own sensor technology. This enables the electronics manufacturer to easily adapt the use of the robots to its dynamic, agile production layout at any time.

Flexible and individual like a family business, yet as professional and top quality as a corporation – this is what ifm electronic GmbH, founded in 1969, represents. The company is a global industry leader in the production of innovative sensors, controllers and systems for industrial automation and digitalization. At its Tettnang facility, around 1800 employees develop and produce items such as position and process sensors, sensors for motion control and safety technology. In order to meet the high quality requirements and to enable optimum production, ifm follows the lean management principle – and also with respect to its intralogistics of course.

“It is important to us that our employees are able to concentrate on value-adding processes. In addition, we wanted to reduce the material on the production lines and ensure just-in-time provision. So, automating our intralogistics was the logical step,” says Ulrich Beller, Lean Manager and Project Manager for AMR Implementation at ifm electronic GmbH. It was also crucial for the company to remain flexible in the dynamic production environment. Therefore, ifm opted for autonomous mobile robots, AMR for short, from Mobile Industrial Robots. In contrast to conventional automated guided vehicle systems, these manage without induction loops or markings on the floor. Thanks to a number of safety functions such as sensors, laser scanners and cameras, they are able to reliably detect stationary and moving obstacles and slow down or take evasive action. When the production layout is changed, the AMRs can therefore quickly be deployed on new routes.

ifm started its automation project in 2018 with one AMR, model MiR100, which supplies material to the lines in a production hall. To do this, an employee requests the robot manually, the robot then docks with the rack developed in-house by ifm, picks up the requested material, brings it to the stored destination and transfers it to the delivery station.

In order to balance the tolerance during docking, ifm integrated its own optical sensor on the robot for the first stage of the process. This checks whether the transport container has been correctly transferred. “A key advantage of solutions provided by Mobile Industrial Robots is that we can use our sensor technology to expand the capability of its robots. This was an important prerequisite for the setting up and expansion of our complex automated intralogistics system,” explains Beller. In addition, ifm is able to set up the software for mapping and program sequence control itself. “We do not require any external support for the programming, having taken on complete responsibility for the development, design and construction of the transfer stations, the commissioning as well as expansion of the system ourselves,” Beller continues.

Automated intralogistics with in-house development

After the initial use of robots showed good results, ifm decided to equip another, very busy production hall with AMRs. To do this, the company further developed its racking system and designed drive-through racks. “Our new development combines container pick-up and delivery in one process. The drive-through racks mean we are twice as quick as with the docking variant and can handle the fast pace and frequency of the order request. We developed the system completely in house and also hold a patent for it,” explains Ulrich Beller.

The system is purely mechanical: When the MiR robot moves through the racking system, a fork is first pressed down to deliver the container. The fork then folds upwards and pulls a new transport container onto the robot. In total, ifm has installed 17 racking systems for collection and delivery, which are equipped with 130 ifm sensors.

MiR Fleet: The robot fleet under control

The order request in the production line is made when an employee removes a container from the delivery buffer of the drive-through rack. The status change of the ifm OJ photoelectric proximity switch mounted underneath the container generates a mission to request a new order. From then on, the AMR takes over collection of the order containers.

For this process, a programmable logic controller (PLC) continuously queries the sensors installed on the racking systems and robots regarding their status change. Should the status of a sensor on the rack or robot change accordingly, the PLC forwards this information to the MiR Fleet control system via a WLAN interface. This distributes the resulting mission to an AMR, which then executes the mission. When assigning the mission, the fleet control takes into account the load status of the AMRs and which AMR is closest to the destination.

Six robots control material transport

Today, six MiR100 mobile robots supply a total of 14 production lines with material across three shifts. They complete more than 1000 missions a day. Each robot covers up to 30 kilometers a day. “The robots have provided great relief for us, because we used to have to carry the heavy boxes through the production hall ourselves,” says Markus Siedenburg, section head at ifm electronic GmbH. “The central provision of the AMR has freed up resources which can be used in a value-adding way. It is only during maintenance work or similar, that we notice the distances and order quantities handled by the robots every day;” Siedenburg continues.

It is not just ifm itself that is convinced by the use of AMR: The self-developed concept of automated intralogistics received the “Factory of the Year” award in 2021. This brought ifm to the attention of other medium-sized companies who also wanted to automate their intralogistics. “As a result of the award, we have received many enquiries from other medium-sized companies wanting to take a closer look at our system. Consequently, we are currently developing a concept for consulting in intralogistics and, in cooperation, the sale of the racking systems,” reports Ulrich Beller. “We are also in the process of installing MiR robots in other ifm plants worldwide. At our own plant in Tettnang, we are currently planning further developments including container recognition. So, there are still plenty of plans on the drawing board!”