CNC_Statement_of_Work_(SOW).pdf

A. Background/History of Requirement: NASA Ames is conducting a high level research program (Mission Adaptive Digital Composite Aerostructures Technologies) as part of the ARMD Convergent Aeronautics Solutions program. Important to this research will be the ability to rapidly prototype laminated assemblies by computerized numerical control (CNC) cutting, perforating, welding, and creasing a variety of materials, including soft thermoplastics (PET, ABS), hard plastics (polyimide/kapton, PEEK), and fabrics (aramid, carbon) of varying size (cutting, perforating, welding, and creasing of 0.001” to 0.050” thick sheets, milling of assemblies up to 4” height, working area at least 4’x8’). The system that NASA Ames Research Center would like to purchase would be used to prototype assemblies for advanced aerostructures and aeromechanical systems research.

B. Requirements Specifications “CNC Laminate Cutting Machine”:

1. General

a. The following specification is for a high-precision computerized numerical control (CNC) cutting, perforating, welding, and creasing system capable of fixturing (i.e. vacuum table) and using a variety of tool-heads to rapidly process thin films, fabrics, and heterogeneous assemblies. Suppliers should propose an integrated system that meets or exceeds the following specifications for the work area, processing capabilities including material capabilities, and supply logistics.

b. The system should be designed to meet or exceed the following Safety, Warranty, Installation, and Support specifications.

c. Specification compliance. In your capability response, please provide documentation that clearly shows that you meet each specification. Please list all specifications in order with annotations stating the proposed system characteristics. If your capabilities are not compliant to a specification, please state the deviation (i.e. 2b Does not meet specification and has a work area of nxnxn dimensions). It is the responsibility of the vendor to understand all specifications.

2. Work Area

a. The work area should be at least 4’2” x 8’2” with overall system dimensions not to exceed 8’x16’; Overall machine weight should not exceed 2500 pounds.

b. The positioning repeatability of the tool-head should be equal to or better than +/-

0.001 inches, with positioning accuracy equal to or better than +/- 0.0015 inches per foot (plus repeatability).

c. The work surface should be able to support at least 5 pounds per square foot of material weight in operation.

d. The speed range of the tool-head should include 1-50 inches per second, with maximum acceleration of at least 350 inches per second squared in the basal plane (XY plane) with a standard drag knife tool installed.

e. Acceptable operating environment temperature should include 50-90 degrees Fahrenheit.

3. Fixturing

a. The system should include an integrated vacuum hold down system that operates with adjustable pressure over multiple vacuum zones.

b. All components of the vacuum system should be physically integrated with the machine and fit within the acceptable footprint specified in 2a, without obstructing access to the machine.

c. Each vacuum zone must be no larger than 12 inches in the largest dimension, and be able to be individually switched on and off without disassembly of the machine.

d. The vacuum system must be designed to work with slightly porous materials (such as fabrics) as well as nonporous materials (such as solid plastics) without disassembly of the machine to switch between modes.

e. The system should produce noise levels no greater than 75dB, measured at expected operator locations including when handling material on the machine.

4. Tooling Characteristics

a. The system should include tool-heads that can be operated under position or force control (Z motion), with the capability of running at a speed of at least 20 inches per second or with at least 30 pounds of force. Acceleration should be at least 400 inches per seconds squared.

b. The system should include a tool-head with an active rotary cutting disc for cutting textiles and composite materials that are at least 3/16” thick. This tool-head should be operable at different disc speeds (including the range of 8000 to 15000 rpm) to accommodate various material melting temperatures, and include continuous temperature monitoring to prevent overheating.

c. The system should include a reciprocating/oscillating tool-head for cutting honeycomb materials that are at least 0.1” thick.

d. The system should include a router / machining spindle tool-head with automated tool-changing for at least eight tools with at least 0.25” diameter shank. With this system in use, it should be possible to fully process materials at least 2” thick (Z direction, meaning that the full cleared Z stroke of the machine must be at least 4”).

e. The system should include a creasing tool-head that operates under force control, with at least 30 pounds of force possible.

f. The system should include a thermoplastic film welding tool.

g. Active orientation of applicable tool-heads should be integrated with the rest of the system software, CAM, and interfaces.

5. Interface and Software Requirements

a. The system should include standard protocol and connector interfaces, such as

RS232 and/or Ethernet and be supplied with documentation necessary to allow the development of custom applications.

b. The manufacturer should provide software/firmware capable of translating a standard numerical control (NC) code into machine positions. This code should be well-documented, with clear instructions on converting a toolpath to commands that are properly interpreted by the system.

c. If no on-board computer is integrated into the system, communication between the computer and the mill should occur over a standard serial or Ethernet interface.

d. The software provided with the system should include the ability to import from and export to standard computer geometry formats including AUTOCAD DXF format and perform standard tool-pathing operations such as cut ordering, part nesting, and tabbing/bridging.

e. The control software should be capable of monitoring tool usage/wear.

6. Safety

a. The machine should include emergency stop switches.

7. Installation, Support, and Warranty

a. NASA Ames can be responsible for uncrating the system, moving the system into its lab and providing the proper utilities for the system.

b. The electronics shall include self-test diagnostics with indicators for hardware and communication status.

c. All items supplied by vendor shall carry at least a one-year warranty against defects in material and workmanship.