Changes between Version 6 and Version 7 of Hand/282/MassProperties

Timestamp:

Aug 16, 2013, 2:47:38 PM (11 years ago)

Author:

dc

Comment:

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Hand/282/MassProperties

@@ -3 +3 @@
 The inertial properties calculated here represent the masses and inertias of each link of the BarrettHand BH8-280. All calculations were made using SolidWorks 2013 SP 3.0 and CAD models that include all mechanical components of the hand (including fasteners) and all electrical components except wiring. To verify that the SolidWorks model was correct, assemblies and parts of an actual hand were massed for comparison. 
 
-The mass of an actual finger was measured at 179 g, which matches the mass of the CAD model. The hand base (including pucks and finger motors) measured 664 g while SolidWorks calculated the mass of the CAD model to be only 643 g. This discrepancy could come from a number of sources:
+The mass of an actual finger was measured at 179 g, which matches the mass of the CAD model. The hand base (including pucks and finger motors) measured 388 g while SolidWorks calculated the mass of the CAD model to be only 367 g. This discrepancy could come from a number of sources:
 
  1. Lack of wiring in CAD
@@ -9 +9 @@
  1. Inadequately modeled PCB and components
 
-Further investigation narrowed the source of error to electrical subassemblies with dozens of strands of wire, all of which were omitted in the CAD model. To replicate the mass of these wires, slugs of the missing mass were created to fill the cavities in which wires could run. The base CAD model used in the calculations below measures 664 g.
+Further investigation narrowed the source of error to electrical subassemblies with dozens of strands of wire, all of which were omitted in the CAD model. To replicate the mass of these wires, slugs of the missing mass were created to fill the cavities in which wires could run. The base CAD model used in the calculations below measures 367 g.
 
 In the following images, all parts are left transparent to display all parts of the mass calculations. Yellow denotes frame parts, red denotes electrical pieces, and blue is for motors and drivetrain components.