By Candi S. Cross
In the IT world, the term future-proof technology has been flung around like the term lean in the industrial engineering world for many years. At its core, the category represents technology that will work decades from now despite evolving processes and product lines. One organization that does not use the words lightly is Bosch Rexroth, the industrial technology, consumer goods and building services engineering company.
In its subsidiary Bosch Security Systems, future-proof technology refers to the AutoDome Modular Camera System – a system based on interchangeable modules that allow consumers to upgrade functionality, adapt to changing security needs and migrate to new tools without having to power down.
With such a serious responsibility to intensive industries, Bosch’s products could not be assigned with mitigating future needs without well-aligned assembly processes. The move to a modular lean work cell system to perform flexible and efficient production is the most recent example of this kind of alignment. There was no better cause for changing an actual production line than the company’s flagship product.
“It’s a surveillance camera with pan/tilt/zoom capability used in security applications,” said Mark Ellis, manager of product assembly at Bosch Security Systems’ Lancaster, Pa., facility. “The work cell we used to produce the previous generation product had long been our proving ground for new lean practices and was our best operational example of lean manufacturing. After a complete redesign, the next generation product was going to be smaller in size, better in performance features and able to be offered at a lower price point to the market. It was also an extremely modular design, and our prospects for business success hinged on our ability to meet customer delivery by manually assembling the modules necessary for any configuration a customer might order.”
The Lancaster site is part of Bosch’s global supply chain network that consists of Bosch-owned factories, or supply centers, together with third-party suppliers. It takes approximately 60 modules from that global supply chain to make all the various types offered within the auto dome family. Lancaster’s assembly of the lean modules occurs as the physical cameras are made by hand. Ellis added that the combination is a perfect example of the pull system, which ensures alignment of the right component with the right department to build a final component based strictly on demand.
Demand comes most from casinos, banks, government buildings, schools and city street intersections, otherwise turf where both people and property must be protected.
“When we say ‘pull system’ we mean specifically one that’s triggered by real customer demand,” Ellis said. “We decided on a pure make-to-order approach for delivery of our auto domes. There would be no finished goods made for stocking purposes, and without that finished goods buffer against customer requirements, we had to set high performance targets for the work cell.”
What an efficient environment looks like
Once evidence pointed to the need to implement a different work cell, the challenge for Bosch Security Systems’ global supply chain network was to offer customers the advantages of a modular design and complete their orders in a one-day cycle. Yes, one day had to account for the product’s manufacturing model already in place: printed circuit board assemblies in the core modules and their variants are supplied to Bosch’s “late-configuration facilities” in Lancaster and in the Netherlands, where they are assembled to meet various customer requests close to the regional demand point.
From the strategic level, all process improvements at the company start with Bosch Production Systems (BPS) that focus on eight principles: process orientation, pull system, perfect quality, flexibility, standardization, transparent process, waste elimination and associate involvement.
After using BPS to direct their redesign plan, Bosch Security Systems partnered with the Linear Motion and Assembly Technologies group, also under the Bosch umbrella of companies, to provide items for the new work cell. Local full-service and automation distribution Airline Hydraulics joined the two groups and provided aluminum structural framing, flow racks, workstation lighting and electrostatic discharge surfaces, which transfer electrostatic charge between two objects in close proximity.
According to Ellis, using the standard camera modules (approximately 60 part numbers), the company is able to produce more than 2,000 top-level products. The work cell design keeps all of the standard modules within reach of the line associates so schedule changes can be made with no changeover. In previous versions of the AutoDome camera, this level of complexity could not be supported even with other kitting operations performed in regional distribution centers.
One part of the lean work cell, the T-slotted aluminum structural framing, has been key to driving out waste that the former procedures created. For example, space savings in the Lancaster distribution center alone amounts to 1,500 square feet and 100 pallet locations. All work components are mounted in easily accessible locations. Additionally, line-side inventory replenishment happens quickly through personnel delivering cartons of raw materials and staging them around the outskirts of the work cell at fixed locations.
Ellis explained: “The Rexroth aluminum framing was used instead of fabricated and welded steel. That’s easier to assemble and easier to change without special tools. The T-slotted aluminum framing allows the workstations to be changed and reconfigured very easily. When we went from our U-shaped line to the L-shape, we pulled one of the workstations completely out of the work cell and also took a large corrugated carton flow rack out of service. We reclaimed the components from both of those stations and built two different workstations for other work cells.”
A benefit to performing this step in house was that the company did not have to purchase additional material. Further, approximately 15 percent of the original purchase cost could be reclaimed without any additional capital investment for other improvement projects.
A “milkrunner” employee maintains the stock levels at each workstation and replenishes the flow rack chutes built into each workstation with enough material to last for two hours. Every employee is trained to be a milkrunner because of this crucial task in keeping the line going. Job rotation occurs on that same two-hour cycle to increase work force flexibility and also as an ergonomic precaution.
The work cell went live with the updated AutoDome camera product launch in January of 2007.
To understand the movement of the upgraded production line, one only needs to consider the parts of the product being manufactured: 16 different camera/lens combinations, three types of housings, three communications modules dependent on protocol of the system the camera is connected to (such as Ethernet support), and numerous power supply, window and mounting options. Additionally, the framing allows for custom add-ons such as instruction manuals or tool holders as needed for each workstation. The tested camera is then disassembled into two parts (housing and camera head) for packaging.
“Our manual production system has kept pace with our team-based continuous improvement initiatives and process changes, meeting or surpassing all the design targets for quality, delivery and cost during the months since we’ve been live,” Ellis concluded. “And during that time we’ve not had one single production stoppage due to the Rexroth line.”