“It’s no wonder that a manufacturing facility for one of North America’s popular SUVs would use rugged, time-proven assembly line conveyors for the vehicles’ construction,” said a Creform spokesperson. “Just as striking, though, are the steel frame automated guided carts (AGC), being used as both traveling assembly stations for the models instrument panel (I/P) subassembly process and as the delivery conveyance for the sub-assemblies to the vehicle assembly line. “The AGCs used at the vehicle maker’s facility are an engineered hybrid of the system developed by Creform Corporation. The carts are driven, routed and controlled by Creform AGC power units while the welded frame, not typically used within the Creformsystem, provides a sturdy, firmbase for the various assembly procedures. Normally, the Creform AGC system carts would be fabricated from the company’s series of plastic coated steel pipes, metal joints and hardware accessories. As one of the maintenance supervisors at the facility reports, the carts were fabricated for durability in what at times can be a severe work environment.” “We built the carts with heavy gauge steel framing for the rigidity that we thought would be advantageous for the assembly process,” the supervisor said. “It turns out that the flexibility of the system, afforded by the ease of installation and the simplicity to modify and rearrange routes, is one of the biggest benefits we found with the Creform AGC system. And, though a single control unit issues timing directives, the fact that each cart is independently powered and capable of individualized responses to isolated commands, offers an additional level of agility that may be required to meet future production layout requirements. “Since the system has been in use, its route has been altered several times. To change a route, one only needs to place adhesive-backed magnetic tape on the floor surface that a cartmounted sensor follows. That’s the guidance system. “As amatter of fact,we’ve recently moved the offloading station of the assembled I/P, to where the unit is mounted in the vehicle on themain assembly line. The new location is working out well, so the AGC line is being reconfigured with a more permanent installation. That simply involves etching the floor with 1/8 inches deep by 4 inches wide channel, then placing the tape in the recess and covering it with a protective epoxy coating. Because the instrument panel carts must cross an extremely high-traffic aisle on its way to reach the main vehicle assembly line, the channel/epoxy mounting method offered a greater level of protection for the tape.” “Though at first, many of the plant’s personnel questioned the concept of theAGCmoving assembly line, the system’s performance has won over even the most skeptical,” said the spokesperson. “The line now has 10 carts running during the two shift operations at the plant. The assembly process of the I/P consists of seven working stations, five of which are where assembly takes place, a quality control station is the sixth, and the seventh is the offload location. In addition, usually two carts with completed subassemblies are queued as a buffer, waiting for offloading while the 10th cart is returned and pre-staged in front of the first assembly station. The entire loop of the I/P assembly circuit is approximately 250 feet long” At the assembly stations, operators install specific components of the I/P in place, which include electronics and gauges, driver’s controls and HVAC. After crossing the busy aisle, the I/P install operator on the main line uses a lift assist mechanism to offload the panel and place it in position in the vehicle’s passenger compartment. Currently, each operator is given approximately 4-1/2 minutes to complete their assigned tasks before the carts provide a warning signal, a safety Delay and finally move on to the next station in line. At one of the stations, Creform has placed an ‘opportunity’ charger where each cart’s battery is given a charge, automatically, every time through the loop. When twin photo sensors verify the presence of a cart, the charger ’s power leads extend to make contact with the charging terminals on the cart. When the carts move, the charger ’s leads retract. In addition, a charging station has been incorporated near the line for reenergizing the batteries of the carts during the overnight down times. The line’s traffic controller consists of two timers. One tracks the stop-time at each station and sends the warning and start signals, while the second controls the timing for the warning alarm (light and horn) and the activation of the queued carts at the aisle. When carts are positioned at the aisle crossing staging area, the alarm starts approximately 90 (adjustable) seconds prior to the anticipated cartmovement. The timing of the cart crossing can vary in that the cart must receive a signal from the controller that the assembly offload area is clear of the previous cart. This all-clear signal is relayed when the I/P install operator finishes the offloading process and manually pushes the empty cart’s start button, sending it on the return loop back to the start station. “The simplicity of theAGC system has allowed us to try several layouts, to stretch out the line and make adjustmentswhere necessary,” the supervisor said. “This would have been prohibitive with most other automated material handling and delivery systems, whether overhead or with imbedded rails. They require time consuming, expensive and disruptive installations. With the Creformguidance system, it’s as close to ‘plug and play’ as one can get, so there’s no constraints to implementing the modifications and improvements.” While numerous applications of theAGC vehicles, like this SUV instrument panel assembly example, utilize custom design and built carts, many other installations of the CreformAGC concept use the firm’s pipe, joints and hardware accessory components to build the carts. ACreformAGC system can keep investment costs low, make guidance system installation easy, instill flexibility of both the cart design and route in the system and free up floor areas with narrow aisle needs as compared to large, wide-turn radius vehicles. Many available accessories are shown including powered and nonpowered roller conveyor beds, various sensors, RF communications, optical guidance systems and multi-function, multi-course PLC controllers. Besides mobile assembly lines, Creform AGC systems can be used for shipping dock truck load/unload, part delivery and container return and tugger-type vehicles. In many applications, Creform users design and build their own material handling solutions. In others, Creform Corporation offers designAssistance and assembly services in addition to furnishing the required components. For more information contact: Creform Corporation P. O. Box 830 Greer, SC 29652-0830 800-839-8823 sales@creform.com www.creform.com