Can I use a timeline with a D3 Force Network? - d3.js

Question

Can I bring this to life with force diagram?
I have a data set that comprises a series of objects that occur along a time line:
letters
orders
memos
phone calls
twitter messages
invoices
emails
The quantity of objects in the data set is driven by a query that extracts relevant objects from a database.
In a simple example there might be 10 objects for a single date or those ten might be spread over 2 or three days or be weeks apart.
All objects are linked, not necesarily directly, to each other.
A might join to B and to C, but D is linked to A only through a link to C.
The links need to be color coded based on the type of link and the line thickness needs to vary to represent the strngth of the link.
I have several ways of displaying this data using fixed coordinates based on the object date. They do the job but they don't look great.
I have created a D3 force diagram that plots the objects (nodes) and draws the links, but I'm at a complete lost as to how I can incoporate the time element.
Is there a way that I can plot the data so that the objects are roughly positioned along a date line? The positions do not need to be exact but the overall result should give the user a good indication of temproal proximity.
I'd also like the links to be drawn with an open B-spline which is something else that I can't get my head around
See sample data and code.
JSON Data
{
"nodes": [
{ "DocID": "77304", "date": "2001-01-21", "Type": "L" },
{ "DocID": "65884", "date": "2001-01-26", "Type": "F" },
{ "DocID": "77005", "date": "2001-02-02", "Type": "L" },
{ "DocID": "66162", "date": "2001-02-07", "Type": "E" },
{ "DocID": "93085", "date": "2001-03-20", "Type": "L" },
{ "DocID": "93101", "date": "2001-03-21", "Type": "P" },
{ "DocID": "93118", "date": "2001-03-28", "Type": "L" },
{ "DocID": "75890", "date": "2001-04-09", "Type": "L" },
{ "DocID": "93189", "date": "2001-04-11", "Type": "L" },
{ "DocID": "93225", "date": "2001-04-12", "Type": "L" },
{ "DocID": "75535", "date": "2001-04-19", "Type": "L" },
{ "DocID": "74916", "date": "2001-05-07", "Type": "I" },
{ "DocID": "58259", "date": "2001-05-16", "Type": "L" },
{ "DocID": "93565", "date": "2001-05-16", "Type": "O" },
{ "DocID": "95504", "date": "2001-05-17", "Type": "O" },
{ "DocID": "74408", "date": "2001-05-21", "Type": "L" },
{ "DocID": "95521", "date": "2001-05-21", "Type": "L" },
{ "DocID": "74343", "date": "2001-05-22", "Type": "L" }
],
"links": [
{ "source": 0, "target": 5, "strength": 9, "colour": 4 },
{ "source": 1, "target": 7, "strength": 4, "colour": 3 },
{ "source": 2, "target": 17, "strength": 2, "colour": 1 },
{ "source": 3, "target": 2, "strength": 3, "colour": 2 },
{ "source": 4, "target": 8, "strength": 9, "colour": 4 },
{ "source": 5, "target": 8, "strength": 5, "colour": 3 },
{ "source": 6, "target": 2, "strength": 3, "colour": 5 },
{ "source": 7, "target": 11, "strength": 5, "colour": 1 },
{ "source": 8, "target": 12, "strength": 3, "colour": 5 },
{ "source": 9, "target": 13, "strength": 9, "colour": 4 },
{ "source": 10, "target": 9, "strength": 4, "colour": 5 },
{ "source": 11, "target": 7, "strength": 5, "colour": 2 },
{ "source": 12, "target": 11, "strength": 3, "colour": 2 },
{ "source": 13, "target": 9, "strength": 3, "colour": 5 },
{ "source": 14, "target": 9, "strength": 2, "colour": 5 },
{ "source": 15, "target": 11, "strength": 3, "colour": 5 },
{ "source": 16, "target": 9, "strength": 6, "colour": 5 },
{ "source": 17, "target": 13, "strength": 4, "colour": 5 },
{ "source": 1, "target": 14, "strength": 2, "colour": 5 },
{ "source": 9, "target": 7, "strength": 2, "colour": 5 },
{ "source": 2, "target": 5, "strength": 5, "colour": 5 },
{ "source": 11, "target": 9, "strength": 7, "colour": 1 }
]
}
JS Code
var width = 960,
height = 500;
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(150)
.size([width, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
d3.json("Resources/testData.json", function (error, graph) {
if (error) throw error;
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.style("stroke", function (d) { return color(d.colour); })
.attr("class", "link")
.style("stroke-width", function (d) { return d.strength; });
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 5)
.call(force.drag);
node.append("title")
.text(function (d) { return d.DocID; });
force.on("tick", function () {
link.attr("x1", function (d) { return d.source.x; })
.attr("y1", function (d) { return d.source.y; })
.attr("x2", function (d) { return d.target.x; })
.attr("y2", function (d) { return d.target.y; });
node.attr("cx", function (d) { return d.x; })
.attr("cy", function (d) { return d.y; });
});
});