Presentation on theme: "Faculty of Mechanical Engineering and Naval Architecture University of Zagreb Croatia ISATP’03 - THE 5th IEEE INTERNATIONAL SYMPOSIUM ON ASSEMBLY AND."— Presentation transcript:
Faculty of Mechanical Engineering and Naval Architecture University of Zagreb Croatia ISATP’03 - THE 5th IEEE INTERNATIONAL SYMPOSIUM ON ASSEMBLY AND TASK PLANNING Session F4B: Production System Design Zoran KUNICA, Ph.D., Assistant Professor Zoran KUNICA, Ph.D., Assistant Professor Professor Božo VRANJEŠ, Ph.D. Ivona TOMIĆ, B.Sc. Ivona TOMIĆ, B.Sc. Development of a Design Procedure for Automatic Assembly System
I.INTRO II.ASSEMBLY PLANNING TOOLS III.PLANNING SOFTWARE CONTENT IV.ASSEMBLY SYSTEM DESIGN: APPROACH & ASSUMPTIONS V.ASSEMBLY SYSTEM DESIGN: AN EXAMPLE VI.FURTHER WORK CONTENT 3
I.INTRO Despite the significant advance in integration of engineering activities and technical systems, concurrent engineering approaches in integration of product design, assembly system design and assembly execution are still of pretty rare occurrence. Especially, CAD/CAE support for assembly system design is still underdeveloped. The goals of the research: upgrading the planning methodology of automated assembly systems,upgrading the planning methodology of automated assembly systems, development of the CAE tools for planning.development of the CAE tools for planning. In this paper, we have tried to identify the procedure appropriate to assembly system design. 4
SUPPORT FOR THE PLANNING OF AUTOMATIC ASSEMBLY SYSTEMS General software I-DEAS CATIA Dedicated integrated software DFMA Adept Digital Workcell Adept Production Pilot COSIMIR Single programs FESTO ProPneu FESTO ProDrive FESTO Gripper Selection Catalogues Third-party solutions.com Within software Manufacturers Research software (science & development) Standards (VDI 2860…) Supporting software companies (Delmia, Tecnomatix, …) II.ASSEMBLY PLANNING TOOLS5
III.PLANNING SOFTWARE CONTENT 6 DFA & ASSEMBLY TECHNIQUES ASSEMBLY SYSTEM/WORKCELL DESIGN (including: catalogues, CAD translators & importers) DEFINITION OF POSITIONS PROGRAMMING PROGRAM OFF-LINE SIMULATION (COLLISION CHECK) PROGRAM DOWNLOAD TO ROBOT/STATION CONTROLLER PROGRAM EXECUTION LAYOUT OPTIMISATION PRODUCTION CYCLE OPTIMISATION FINANCIAL METRICS DIGITAL I/O AND WIRING DIAGRAMS
7 Development approaches CAD-basedProgramming-based Assembly-based
The basis for assembly system design is appropriate ASSEMBLY PLAN, which defines: defines: n assembly sequence, n assembly paths, n parts' positions (before and after assembly), n assembly operations. Assembly paths and operations imply principal technical solutions of particular assembly devices (device type, number, kinematics and dimensions) within assembly system. The equipment – devices, for assembly system is defined in three ways: choosing among existing equipment, choosing among existing equipment, modification of the existing equipment, modification of the existing equipment, design of entirely new equipment. design of entirely new equipment. Devices are modelled interactively and automatically during CAD session, and using CAD libraries and catalogues, which possess parameterised design base of devices. The manufacturers or third party companies (Part Solutions) make equipment available for download on internet, also. IV.ASSEMBLY SYSTEM DESIGN: APPROACH & ASSUMPTIONS 8
A concept of the assembly system development PROCESS STRUCTURE & OPERATIONS DEVOTER non-standard components CATALOGUE standard components DEVICES SYSTEM INTEGRATOR ADJUSTING OF DEVICE DESIGN 9
AAssembly process/system planning a product -- an assembly, exists as CAD model assembly and disassembly are inverse issues a product is a virtual mechanism, that should be recognized during planning stage an assembly system is a complementary mechanism non-standard components PRODUCT (ASSEMBLY) ASSEMBLY SYSTEM standard components mechanism I – assembly paths mechanism II – components` motions 10
An assembly planning environment should combine tools distributed in two levels: 1.pretools within activities prior to assembly planning, 2.assembly planning CAE component (posttool) that follows product design process. Assembly planning and activities of product design 11
Discrepancy in orientation: natural orientation of the part (A), technological orientation (B), orientation required in a product (C) 12
Origins of orientation definition 13
Example of definition of plan generation parameters ASSEMBLY PLAN GENERATION OPTIONS Product class Planning procedure should be analysed as a combination of automatically and interactively generated elements. 14
TThompson's examples of variations of living organisms (1917) n Variants/variations of products Duerer's ( ) examples of variations of living organisms Two solutions of the same mechanism (Blanding, 1999) 15
Some of the structures for a product with six parts (Beneath the graphical presentation of each structure the structure’s numerical code is given.) n Variations of assembly process The assembly process can be represented and modelled using generic structures – generic plans. The structures show the space and time possibility of the assembly process realisation. 16
xz – horizontal plane n Variants of product`s initial orientation Hi6Hi5 Hi2 Hi4 Hi3 17
n Variants of parts’ layout Rotary-table (D = 1234,212 mm) Line assembly (L = 8639,487 mm). Hi5 Hi4 Hi2 Hi3 Hi6 z distance Hi5-Hi6: 5924,22 mm 18
n Treatment of identical parts in a product Disassembled product... Without taking into account identical parts... Taking into account identical (yellow) parts... Savings in space and equipment! 19
n Variants of equipment’s manufacturer ABB IRB 140 FANUC LR Mate 100iLR Mate 100iAdeptSix 300 n Variants... variants... etc
xz – horizontal plane n A product – assembly Hi2 Hi7 Hi3 Hi5 VI.ASSEMBLY SYSTEM DESIGN: AN EXAMPLE 100 mm 75 mm 75mm 21
Hi3 Hi5 n Disassembly simulation (sequence and paths, and positions of parts before assembly) Hi2 Hi7 t Hi7 = 397 mm t Hi5 = 397 mm t Hi3 = 265 mm t Hi2 = 265 mm Top view 22
23 Variant I Double acting cylinder DSNU P-A There are four identical pneumatic cylinders. The cylinders push parts from their positions before assembly, towards required final positions, to make the assembly. The cylinders are pretty long, implying a larger necessary space. The parts come in the assembly process in ordered state -- magazines. Assembled product is removed from the assembly spot by a murder hole.
24 Double acting cylinder DSW-32-P-B Variant II Almost the same as the variant I. There are also four identical cylinders, but of another type – with shorter strokes. In that way it was possible to place parts closer to the assembly spot (correction of position values obtained by assembly plan). The cylinders in both variants (I & II) are chosen among many available, and applicable to this specific situation.
25 Linear module HMP Parallel gripper HGP Variant III The assembly system consists of four identical manipulators, each containing two linear modules, and having identical grippers. Additionally, there is also a pneumatic cylinder for the part Hi7. Three manipulators with their grippers carry the parts to the required final positions. The fourth manipulator takes the part Hi7 and delivers it at the pneumatic cylinder, which pushes the part in its final position within the product. Since the manipulators have only two DOFs, included pallets should be movable (two DOFs).
26 Vacuum gripper VAS-30-1/8-PUR Variant IV The variant IV is similar to the variant III, except a robot equipped with a vacuum gripper is added to the part Hi7, so the cylinder from the variant III is obsolete.
27 Variant V The variant V is the enhancement of the variants III and IV. The main difference -- three robots (with four DOFs each) are used in the variant V, instead of manipulators in the variants III and IV. Consequently, movable pallets are no longer needed.
28 Variant VI Three identical robots from the variant V are replaced with one single robot. The savings in equipment cost and space are obvious, but assembly cycle will be longer.
29 Variant VII Only one single robot with four DOFs, will assemble the whole product. Since the part Hi7 requires different gripper than the rest of the parts, the assembly system should involve a possibility of gripper change. Neglecting the gripper change subsystem, the variant VII carries further cutting of equipment and space costs. However, the assembly cycle becomes longer.
30 Variant Equipment Ranking criterion Productivity, 60 % Price, 25 % Flexibility, 10 % Space, 5 % I 4 pneumatic cylinders DSNU P-A, magazines, murder hole 45344,15 II 4 pneumatic cylinders DSW-32-P-B, magazines, murder hole ,8 III 4 manipulators+grippers, pneumatic cylinder, movable pallets, murder hole IV 3 manipulators+grippers, robot+vacuum gripper, 3 movable pallets, fixed pallet, fixed pallet for assembled products 32532,95 V4 robots+grippers, 5 fixed pallets31522,65 VI2 robots+grippers, 5 fixed pallets23542,65 VII single robot, 2 grippers, five fixed pallets 14552,35 Comparison of the assembly system variants
VII.FURTHER WORK S. Freud & Eric Berne`s transactional analysis Detailed variant design of devices, including: analysis and optimization of (dis)assembling paths (directions and lengths), simulation of assembly operations and assembly techniques (forces, deformable joints - snap fitting,...). Implementation of assessment criteria. Automation of the design procedure. Experiments with concurrent generation of assembly plans and systems. Modelling of CE planning situations and roles (procedures, protocols and data sharing). Human planner's mental activities and behavior -- conscience and non- conscience (intuitive) aspects of the planning. 31