This document proposes the developement of a general purpose crane simulator targeted to operator training and deferred control. Based upon technology similar to aircraft and vehicle simulators, the Virtual Crane would realistically reproduce the movements, operations and limits of a given class of cranes. Using a hardware and/or software reproduction of the control interfaces, the Virtual Crane operators would be able to interactively drive one or several Virtual Cranes simultaneously, moving objects in a lifelike working environment, training in crane handling with different kinds of loads and tasks. These simulations can optionally be stored as animations, and can later be played back, modified, filmed from different viewpoints. Finally they may be used to digitally control real cranes.
This document consists of an introduction to simulator technology, followed by a thorough description of the Virtual Crane idea and its implementation phases, as well as equipment and manpower estimates.
Virtual Reality has introduced a totally new way of interfacing to robots. By the intermediate of a Virtual Prototype, the operator only works on graphic representations of objects, using "Virtual Tools". The action performed in the Virtual Environment, is then transmitted on line (Telepresence) or after validation (Delayed Teleoperation) to a robot, which is programmed automatically as a byproduct of using the Virtual Tool. The result is the elimination (or at least minimization)of the human error factor from the construction budget.
If aircraft and vehicle simulators are mainly intended to train a human's piloting skills, or to evaluate ergonomic appreciation of the vehicle before construction, a crane simulator would go even further, becoming a central part of any complex assembly or construction. Designed as a general, configurable toolkit, able to "impersonate" any crane of a given type and equipped with software and hardware control interfaces, the simulator would give the operator the look and feel of the real crane, operating within a virtual environment representation. Feeling "immersed" in the virtual world, the operator behaves like he/she would on the real site, visualizing in real time the results of his/her actions and instantly correcting the path in case of unwanted effects. The amount of realism that can be built in the virtual operation theatre is an important ingredient in rapid reaction and learning. This realism involves a photorealistic 3D graphics environment, but also real world physics simulations, such as gravity, collisions, dynamics, kinematics, material deformations and elasticity, and even meteorological forces and events. Like in aircraft simulation, the operator has the perfect feeling of "being there" and is able to test without risk hazardous situations and manoeuvres.
Apart from its training and trial benefits, a crane simulator has a real potential of being useful in the construction planning. In fact engineers can use the simulator to instantly create animations of crane movements and objects displacements, stacking and assembly. These visualizations can greatly help in dynamic space and volume management of the building site, during the different construction phases, particularly in situations of limited operation area. Planners can explore different scenarios and choose the most efficient one. These animations have the added benefit that they can be stored and downloaded to the real cranes, allowing robotic construction without human intervention and without programming. In fact, the cranes are programmed as a byproduct of making the animation.
Manpower estimate: 36 man/months
Manpower estimate: 18 man/months
Manpower estimate: 18 man/months
1 x SGI ONYX2 IR, 4 R10000 CPUS, 512MB RAM, 16GB HD.......USD 200K 3 x SGI O2, 128MB, 4GBHD ................................ USD 50K 3 x PC compatible W'95 + NT ............................. USD 20K 5 x DIVISION's Dvise developement sw licenses ........... USD 120K 1 x MULTIGEN II sw license .............................. USD 30K misc. software packages and infrastructure .............. USD 50K misc. VR I/O peripherals ................................ USD 30K staff training (dVISE) .................................. USD 20K -------- Total.................................................... USD 520KThese figures are based on market quotes and estimates valid in Switzerland. Generally, one should expect them to be lower in the US. I have no information about value ratio in Canada. This estimate does not include the "immersive screens" for the simulator cabin and the related control equipment. Costs may vary largely depending upon the degree of immersion required. A basic system may be priced around USD 80K, and a high end one may get to USD 300K. Also, note that labour and ordinary office equipment are not included in this estimate.
PL: Project Leader GR: InfoGraphist IO: I/O specialist (programmer) CE: Crane Engineer VR: VR and 3D graphics specialist (programmer) CA: Crane animator (programmer)
NOTE: If the CE has a good experience in OO and VR programming, then the CE and CA could be the same person, hence the need for a CA would drop.
Month 1: setup and get going - Lab installation.........................................ALL 1w(eek) - team installation and planning - SGI cluster configuration - products installation - CAD interfaces and scripts - Team training............................................ALL 1w - a 1 week on site training course (dvs/dVISE) - Dev model construction...................................ALL 2w - import + optimize CAD crane model - build basic construction site models - build initial object database - build basic crane animation model Month 2: toolkits, databases, schemes construction - Object database...........................................VR 4m(an)/w(eeks) - objects definitions - property & behaviour definitions - standard database functions (add, delete, list) - graphic interface (object palettes) - Virtual construction site 1 (part 1)......................GR 4m/w - create first virtual training environment - CAD object import interface...............................PL 2m/w - build automatic import scripts - Crane/Hook behaviour phase 1...........................CE,CA 8m/w - build and program mathematical models - implement basic functions (grab/release) - I/O preliminary dev ......................................IO 4m/w - virtual control box with data stream generation Month 3: numerical models and I/O development - Crane/Hook behaviour phase 2...........................CE,CA 8m/w - build and program mathematical models - I/O dashboard dev.........................................IO 4m/w - RS232 connections and readouts - data stream parametrization and transmission - Shadow simulation.........................................PL 2m/w - hook and moving object - 3D stereo tuning..........................................VR 2m/w - stereoscopic adjustements - events recording/playback.................................VR 2m/w - VCR style control box - Virtual construction site 1 (part 2)......................GR 4m/w Month 4&5: dynamics, kinematics, object behaviour - Advanced crane/hook kinematics.........................CE,CA 4m/w - acceleration and swing - cable stretch and wind/unwind - Crane direct and inverse kinematics....................CE,CA 4m/w - free and constrained rotations - Human partner simulation..................................VR 8m/w - manikin animation - Sound effects.............................................IO 4m/w - mechanic sounds triggering - manikin signalling and communication - Objects kinematics.....................................CE,CA 8m/w - gravity effects (drop, roll, hit) - collision dynamics (movement transmission) - basic materials effects (flex, break) - Virtual construction sites 2 and 3........................GR 8m/w - Force feedback ...........................................IO 4m/w Month 6: optimization, industrialization, debugging - product consolidation....................................ALL 4w