{
		 "name": "em-ex",
		 "cartridges":[
		             {"name": "cart1",
					 "diameter" : 0.028,  
					 "length": 0.255
					 },
					 { "name": "cart2",
					 "diameter": 0.032,
					 "length": 0.420
					 },
					 { "name": "cart3",
					 "diameter": 0.038,
					 "length": 0.385
					 }
					 ],
			"geometry":{
						"hdiam": 0.045,
						"emptyf":0.127,
						"width":4.5,
						"abutmentH":4,
						"archHeight":0.5,
						"g":0.05,
						"a":0.01,
						"b":0.02,
						"Q":4.03,
						"V":0.92,
						"Density":1200,
						"c":0.4
					}
					
					
					 
				
}