Context 1 … the two-motor H EKTOR. The X-configuration was accomplished by feeding the lower cable horizontally to a pulley fixed at the lower right corner of the reference frame. This pulley guided the cable to the bottom of the end-effector, which was then fixed to a steer at the lower left corner of the character frame. The lower cable ’ randomness pulley was attached via a sling around the body of the end-effector. This allowed the pulley to move freely underneath the end-effector, which minimised the leaning for the lower cable to tilt the end- effector during operation. Tilting ( rotation of the end- effecter so it is no longer convention to the workspace ) occurred when the end-effector was positioned at the extreme point left or right bridge player side of the workspace. careen of the end-effector was undesirable as it would result in positional errors of the tool center point, which would cause inaccuracies when paint. however, the employed X-configuration, along with the lower cable tensioned by the lower drive in stream modality, provided effective stabilization of the end-effector and minimal cant, which allowed for accurate position. P ICARSO transforms an input prototype using the modernize picture process software to produce a coveted output. The image action output was converted into commands by the control software. These commands were then sent to the electronics, which manipulated the end-effector and painted the picture. detail descriptions of these sub-systems of P ICARSO are provided in the follow sections. Within P ICARSO ’ s mechanical system, centrifugal mounts were designed which provided the mounting structure for a drive, a drive control, vitamin a well as the cable arrangement. furthermore, the end-effector housed the paint mechanism. The comply sections outline the design development of the components of the mechanical organization. The centrifugal mounts were designed to provide a modular and portable structure to attach the drive system, control system and cable system to the erect surface. The drive and operate systems consisted of the motor forum and control hardware respectively, while the cable system comprised of the cables, the spool and the cable feed system. The final design of the upper left motor saddle horse is seen in Figure 4. Each motor was mounted parallel to the painting surface on an aluminum fish bracket fixed to a base plate designed to mount immediately to a vertical paint surface with bolts. To control the gesture of the end-effector, a double over bobbin and coupled bear were attached to each motor to wind two cables simultaneously. Two cables per motor were used to keep the end-effector normal to the workspace and reduce the kick-back when air was expelled from the atomizer artillery. besides, in the consequence of one cable failing due to excess tension, the second cable would be able back the load, minimising damage to the arrangement and increasing safety. The cables are reorientated from the winding plane to the working plane through eyelets and pulleys attached to the motor mounts. The lower plate uses fairleads in invest of the pulley to allow for 180° sweep of the cable. The aim of the end-effector design was to secure the paint mechanism for the P ICARSO system and for it to be integrated into the mechanical system for positioning and stabilization of the painting mechanism. The painting mechanism chosen for the P ICARSO system was an automatic pressure-fed spray gunman ( Anest Iwata SGA-101 ). Automated atomizer guns are robust and provide repeatable results through a solenoid controlled spray. Analog signals from a data acquisition ( DAQ ) card were used to switch an electronically actuated solenoid to control the spray accelerator ’ sulfur process. The paint used for pressure-fed spray artillery is located outwardly from the spray gunman in a pressurize paint canister. therefore, when the paint is used up during operation, the weight of the spray accelerator remains unchanged, and therefore does not affect the dynamics of the system, thereby making control easier. The choose pressure-fed spray artillery has the ability to paint onto vertical surfaces and to house enough paint to paint a 3×3 meter come on area in one continuous operation. The meet end-effector caparison the spray gun is shown in Figure 5. This plan comprised of an aluminum sleeve which encased the spray grease-gun from behind. This atomizer gun and sleeve were located inside a larger cylindrical sleeve which allowed free rotation of the spray gunman about the axis of its beak tip. This ensured that as the end-effector moved through the workspace, the positional error of the nozzle lean would be minimised, despite rotation of the out cylindrical sleeve. The outer sleeve was besides designed such that it did not obstruct the publicize and fluid lines of the spray gun in the smaller inner sleeve. Three pairs of 120° space eyelets were placed around the away of the larger cylindrical sleeve which allowed connection to the motive mounts through the cables. An explode opinion of the house can be seen in

Figure 6

. The electronics provided communication between the software and hardware to control the system. The electronics consisted of the force arrangement, control arrangement and complementary hardware. The campaign system encompassed the motors and any extra hardware required to manipulate the end- effecter by spooling cables to their coveted lengths. Three Maxon Motor EC45 motors with a 26:1 gearhead were selected, which were adequate to of a maximum continuous torsion of 6.6Nm, and operating at approximately 175rpm. The control system consisted of the hardware used to send command signals to the system actuators, which consisted of three Maxon Motor EPOS2 70/10 motor controllers, and three optical encoders and gearing head assemblies. The extra hardware implemented in P ICARSO included a National Instruments PCI-6221 DAQ menu to convert the digital signal motor command to an analogue sign that could be sent to the motor accountant as an analogue remark. Control using analogue inputs was selected to command the stead of the two amphetamine motors in order to eliminate latencies associated with the drive accountant firmware when using series or USB communication. As previously stated, the spray gun used an electronically controlled solenoid valve to actuate when required. A tripartite solenoid valve was used as a interchange for the air inlet to the spray gun and controlled using an analogue end product from the DAQ card. Through testing, this was deemed to be appropriate for the switching frequencies required for this application. The see software required inverse kinematics to convert the persona march output signal into motor put commands used by the upper two motors to move the end-effector. To determine the inverse kinematics, the workspace, reference frames and proportional placement of the components of the organization are defined, as seen in Figure 7. due to being controlled by specifying torsion, inverse kinematics for the botto meter drive was not required. The inverse kinematics of the system were derived as …

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