Loads #

• Load elements must have a id property of type string.
• Currently supported are load elements of type of ['force', 'spring'].

Force #

• Forces are acting on nodes exclusively. The p property references a node by its id.
• The force value value must be a positive number greater than zero interpreted as [N]. Default is 1.
• Initial force orientation can be set by w0 in [rad].
• Force orientation can be static or dynamic. In the dynamic case the orientation is referred to the orientation of a constraint specified by wref as a valid reference. w0 is interpreted as an offset to the referenced constraint then.
• A drawing mode mode as one of ['push', 'pull'] specifies, how the force arrow is rendered. Default is pull.

Example: #

{
    "gravity": true,    
    "nodes": [       
        { "id": "A0", "x": 100, "y": 120, "base": true},
        { "id": "A",   "x": 200, "y": 120 }
    ],    
    "constraints": [
        { "id": "a", "p1": "A0", "p2": "A", "len": {"type": "const"}}
    ] ,
    "loads":[{
        "id":"F1","type":"force","p":"A",
        "value":30,"w0":1.5708,"mode":"push"
    }]
}

Spring #

• Springs are acting between to nodes. They are required to have two valid references p1 and p2, just like constraints.
• The spring rate k must be a positive number greater than zero interpreted as [N/cm]. Default value is 1.
• Initial spring length of the unloaded spring can be set by len0. If not specified, the initial distance between p1 and p2 is taken.

Example: #

{   
    "nodes": [
        { "id": "A0","x":200,"y": 200, "base": true },
        { "id": "B0","x":100,"y": 100, "base": true },
        { "id": "A","x": 200, "y": 100 }
    ],
    "constraints": [
        {
            "id": "b","p1": "B0","p2": "A",
            "len": { "type": "const" }
        }
    ],
    "loads": [{
        "id": "a", "type" :"spring",
        "p1": "A0", "p2": "A", "k": 20
    }]
}

Example: #

{  
    "gravity":true,
    "nodes": [
        { "id": "A0", "x": 175, "y": 50,"base": true },
        { "id": "B0", "x": 175, "y": 100,"base": true },
        { "id": "A", "x": 225, "y": 50 },
        { "id": "B", "x": 325, "y": 50 }
    ],
    "constraints": [
        { "id": "a", "p1": "A0", "p2": "A", "len":{"type":"const"}},
        { "id": "b", "p1": "A", "p2": "B", "len":  {"type": "const" },
          "ori": { "type": "const", "ref": "a" } }
    ],
    "loads": [
        {
            "id": "s", "type": "spring",
            "p1": "B0","p2":  "A","k": 78.695, "len0": 0 
        }
    ]
}