PRODUCTION plants with robotic welding lines can address the entire spot welding design process while taking into account critical factors such as space constriction, geometric limitations and welding cycle times.
eM-Spot, part of the Tecnomatix software suite distributed in Australasia by plm , enables users to design and optimise spot welding processes in a 3D graphics environment.
An interactive interface leads a user from development of work cell layout, through creation of welding points and robot paths, to the generation of fully validated robot programs.
Powerful features such as 'gun' search, automatic robot placement, path cycle time optimisers and weld point management tools enable the user to create virtual cells, simulations and programs that accurately reflect the physical cell and robot behaviour.
eM-Spot also enables off-line program of robots, so that no production is lost due to equipment downtime.
* Two-way data transfers to it from various CAD/CAM Systems.
* Libraries of robot, gun and component models.
* Advanced tools for weld point management, including MS Excel compatible embedded spreadsheets.
* Kinematics modelling of robots and devices.
* Static and dynamic collision detection.
* Automatic placement of robots in the work cell.
* 2D and 3D cross-sectioning.
* Automatic selection of optimum gun assemblies.
* Simulation of robots and humans, part flow and mechanical operations.
* Automatic generation of robot programs.
* Work cell sequence of operation defined as input for PLC, logic and control programs.
Designing a cell layout
To design a cell layout, the product enables the user to design robotic spot welding cells and station layouts, quickly and easily, using car part and weld point data from CAD systems. 3D models of robots and standard peripheral components can be used in the user-defined library, or new models can be created using the system's modelling tools.
Accessing CAD models directly
eM-Spot uses the native master product data that resides in the CAD system. This seamless integration allows full associativity between the process and the updated traditions of the CAD or parts, thus ensuring that the process is always up-to-date with the latest product changes.
Selecting the best gun
To select the best gun, the product automatically creates sections by slicing weld point fixtures and work pieces. These cross-sections are used to perform an analysis of parts for the gun search and to investigate specific zones of interest.
Using the sections, eM-Spot enables the user to select the optimal gun for a particular spot welding job. The system automatically proposes the most suitable solutions from the user's gun library in order of priority. This, based on welding point information, part geometry and required welding parameters.
Alternatively, users can design a new gun or modify an existing one using the system's 3D solid modelling tools, and the dimensions of cross sections of the work piece.
Optimising robot placement and path (trajectory)
The software verifies that the robot reaches each welding point without colliding and interfering with other robots, fixtures and work pieces. eM-Spot automatically adds 'via points' to the path to minimise robot cycle while avoiding collision. The defined robot path can be modified automatically or interactively.
eM-Spot enables the user to manipulate individual robot joints, redistributing motion effort among the joints to eliminate bottlenecks. The system graphically displays cycle times, collisions and motion efforts.
Generating verified robots and PLC programs
The product enables the user to simulate individual robot and entire work cells. Using the systems Gantt chart feature, users can define and simulate welding operations, activation of guns and tools, as well as other logic events and signals. The resulting optimised, validating robot and PLC (logic and control) programs are then downloaded to the shop floor.
This has many benefits including the detection of simulation problems at early planning stages, reduction of shopfloor installation, and increased quality of robot programs.