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Castable Bulk Metallic Glass Strain Wave Gears: Towards Decreasing the Cost of High-Performance Robotics
Douglas C Hofmann1,2, Raul Polit-Casillas1, Scott N Roberts1
1Engineering and Science Directorate, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr. Pasadena CA 91109, USA.
Scientific Reports
|November 25, 2016
Summary
Bulk metallic glasses (BMGs) offer a low-cost alternative to steel for flexsplines in strain wave gears (SWGs), potentially reducing robotics costs. Their properties also suit extreme environments like spacecraft applications.
Area of Science:
- Materials Science
- Mechanical Engineering
- Robotics
Background:
- Strain wave gears (SWGs), or harmonic drives, are precision gearboxes relying on a flexible component called a flexspline.
- Traditional flexsplines are typically made from steel, involving costly machining processes.
Purpose of the Study:
- To investigate the feasibility of using bulk metallic glasses (BMGs) as a flexspline material in SWGs.
- To explore the potential for cost reduction and enhanced performance in SWGs through the use of BMGs.
Main Methods:
- Casting of bulk metallic glasses (BMGs) for flexspline fabrication.
- Evaluation of BMG properties (hardness, elastic limit, yield strength) relevant to SWG performance.
- Comparative analysis of BMGs versus traditional steel in SWG applications.
Main Results:
- BMGs can be manufactured at significantly lower costs compared to machined steel components.
- The inherent properties of BMGs, including high hardness and strength, align with SWG requirements.
- BMGs present a viable alternative material for flexsplines, promising reduced SWG manufacturing costs.
Conclusions:
- The use of BMGs in SWGs offers a pathway to substantially lower the cost of precision robotics.
- BMGs demonstrate potential for use in demanding, extreme environments, such as those encountered in spacecraft.
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