# Experimental Study of the Vibrations of a Roller Shutter Gripper
## 3 Materials and Methods  
Designed and built by the authors as part of the R&D project, the roller shutter gripper is a multifunctional device that allows the handling of whole layers of products with dimensions of 1300 \(\times\) 800 mm, separators and pallets. The weight of the gripper is 197.4 kg. Pneumatic systems are controlled by a pressure of 6 bar. The gripper is equipped with two AC motors used to drive the roller shutters. The programmable logic controller (PLC), which is an integral part of the device, is responsible for the correct operation of the gripper. The PLC's software allows the realization of tasks (handling of goods, separators and pallets), taking into account information from sensors. The communication of the gripper with the robot was conducted via Ethernet [42]. The roller shutter gripper is a modular design consisting of a base frame, guides with roller shutters, and an adapter that attaches the gripper to the robot flange (Figures 4 and 5).  
Figure 4: General views of the roller shutter gripper. (**a**) Front view, (**b**) side view, and (**c**) top view.  
The base frame was designed as a double cross pattern made of light and rigid aluminum profiles ITEM 40 \(\times\) 80. The dimensions of the frame were chosen to allow gripping the layer of products with dimensions of up to 1300 \(\times\) 800 mm. Two roller shutters were designed, which run along the longer side of the pallet and converge to the center of the pallet when the gripper is closed. The drive system of the rollers is designed as two symmetrical chain modules moving in the side modules (Figure 6). TSUBAKI's ISO 12B-1 modular chain was used as the moving element. The chain is shaped using modules with embedded sprockets. The supporting element of the module is a lightweight aluminum profile ITEM 40 \(\times\) 40.  
The chain moves in a slider made of durable material with a very low coefficient of friction. As a result, the load from the products is not transferred to the chain and sprockets but to the slider and the gripper base structure. The chain modules are bolted to the gripper base frame and connected by rollers. For handling product layers of the required size and weight, steel rollers of the INTERROL 1200 series with a diameter of 30 mm and a load capacity of max. 120 N were used. The proposed gripper concept imposes special requirements for picking up goods from the production line. Rollers can be driven by an additional belt conveyor placed under the gripper at the pick-up point. This ensures smooth entry of the goods into the gripper. Figure 7 shows the main dimensions of the gripper.  
Figure 5: Isometric view of the roller shutter gripper. 1—Base frame, 2—guides with roller shutters, 3—motors, 4—adapter attaching the gripper to the robot flange.  
Figure 6: Side module of the roller shutter gripper. (**a**) General view; (**b**) chain guide.  
Table 1 shows the gripper parameters, such as the position of the center of mass, relative to the X0Y0Z0 coordinate system located on the robot flange, moments of inertia \(L\) relative to the center of mass of the gripper and moments of inertia \(I\) relative to the X0Y0Z0 coordinate system. Those parameters were determined using the gripper CAD model in the SoliWorks CAD software.