Finally, we can find larger floating cranes, generally used to build oil rigs and salvage sunken ships. Some lifting machines do not strictly fit the above definition of a crane, but are generally known as cranes, such as stacker cranes and loader cranes. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources.

Unsourced material may be challenged and removed. (November 2011) ( Learn how and when to remove this template message)Ĭranes were so called from the resemblance to the long neck of the bird, cf. The crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC. The archaeological record shows that no later than c.515 BC distinctive cuttings for both lifting tongs and lewis irons begin to appear on stone blocks of Greek temples. Since these holes point at the use of a lifting device, and since they are to be found either above the center of gravity of the block, or in pairs equidistant from a point over the center of gravity, they are regarded by archaeologists as the positive evidence required for the existence of the crane. ).ĭo you think this can be done using parameters & actions? If yes, is anyone able to give me some tips & tricks? Please let me know if I should specify both questions some more.The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. attachment) Ģ- Attaching a rotating jib to the rotating main boom (The Main Boom rotating point keeps rotating along with the jib rotation. However there are still some issues:ġ- Controlling the main boom rotation by parameter 'RADIUS' (horizontal parameter, ref. Up till now I managed to build a telescoping, rotating, main boom using parameters & actions. I've attached two of my test models to give you an idea on the required motions (two jib types). I now found out that the constraints can give you a headache! I am probably better off using parameters & actions only. The number of constraints in this model is a lot larger than the numbers in my test models. Although I found warnings on this forum to be carefull with dimensional constraints I found them relative easy to use and I've choosen the constrants to build a few test models.īased on these models I've now built an actual full crane model (side and top view). Dynamic blocks are very helpfull for this and save a lot of time. These will be used for preparing 2D lift plans. I'm currently working on dynamic blocks of telescopic mobile cranes.

Model 351 jib crane cad