Apparatus and Method for Reduced-Gravity Simulation


Mechanical and Aerospace Engineering Department, College of Engineering

Apparatus and Method for Reduced-Gravity Simulation;
Multi-Degree-of-Freedom Test Stand for Unmanned Air Vehicles;
Six Degrees of Freedom Free-Motion Test Apparatus

(September 28, 2012)  At a Research Rally today, New Mexico State University celebrated a mechanical and aerospace engineering professor for receiving a U.S. patent on reduced-gravity technology that can not only train astronauts to work in space, but can also help persons with disabilities who have walking impairments.  NMSU Professor Ou Ma, along with Jiego Wang, of Brampton, Ontario, Canada, received a U.S. patent for their project, “Apparatus and Method for Reduced-Gravity Simulation.”  “There are several applications this technology can be used for,” Ma said. “It can be used to train astronauts or other space travellers who will be doing physical activities in space. There are applications to help a person with physical disabilities or injuries that can help them offload some of the weight so they can train or rehabilitate.” 

Ou MaPhysical simulation of human activities in a reduced gravity condition on Earth is often needed in aerospace and biomedical research. Simulation of a reduced gravity condition for a person requires that the person’s body parts experience the forces and movements consistent with that condition.  This research investigates an innovative reduced- or zero-gravity simulator based on passive gravity compensation. The simulator can offload any amount of the body weight of a person so that the person moving within the mechanism will feel as if he/she is on another planet with less weight.  The technology has an auto-balancing system that automatically adjusts to accommodate the weight of different subjects. It also has a pair of supporting harnesses that allow a person in the system to be comfortable and firmly supported through all range of motion. The device is surrounded with a 12-camera motion capture system that accurately measures the motions of all the human’s body parts. The underneath dual-belt treadmill will collect all the ground reaction forces exerted on the human feet.

Besides applications to train astronauts and assisting persons with injuries or walking impairments, this equipment system can also analyze the walking gait of elderly patients who are prone to falling, provide gait training for athletes who want to perfect their stride, provide data analysis for golfers wanting to improve their swing and spot areas that need correction, and can also simulate satellite tumbling.  Ma said their next goal is to focus on applications of the new technology.  “In the next year, our main focus is going to be on testing this technology on humans and seeing how it performs,” he said.

Ma, Carlos E. Ortega, and Ken Ruble, both mechanical engineers at NMSU, have a U.S. patent pending for their “Multi-Degree-of-Freedom Test Stand for Unmanned Air Vehicles” technology. This invention is a multiple degree-of-freedom test stand for unmanned air vehicles, and is particularly useful for small or micro unmanned air vehicles. The stand is gravity balanced using springs so that no weight of any part of the stand becomes a burden to the tested vehicle when it flies while constrained to the stand.

In August, Ma and Ruble filed a U.S. provisional patent application for a “Six Degrees of Freedom Free-Motion Test Apparatus.” A prototype of the rotating satellite test bed was recently presented to the Air Force Research Laboratory at Kirtland Air Force Base.  Additionally, Ma is working on technology that focuses on gravity augmentation, with applications in the space, healthcare and sports industries.

“This work is beneficial to NMSU because we have a new aerospace program,” Ma said. “We cannot teach students aerospace engineering only with chalk and blackboard in the classroom. We need some experimental infrastructure; we need some equipment so that students can experience, see and hands-on learn from the engineering reality.”

– Article by Audry Olmsted; photo by Darren Phillips.  See more at

<prior rally   following rally>