Two South Bay tech companies have built a virtual reality skydiving simulator to help smokejumpers and military special forces hone their free-falling skills while safely dangling a few feet off the ground.

The module uses a parachute harness and a virtual reality headset powered by Microsoft’s Kinect v2, a video game sensor that responds to body movements and voice commands.

Systems Technology, which developed the Parasim skydiving simulator in Hawthorne with the help of Torrance-based Motivo Engineering, is one of hundreds of software developers that have received prototypes of a Windows-enabled, open-source version of the Kinect that will become commercially available later this summer.

The Kinect software development kit, or SDK, is part of Microsoft’s push to foster nongaming uses of its voice and gesture recognition technology. Several companies are already using the Kinect for medical care, education and border surveillance.

Microsoft released the first generation of the Kinect in 2010 in an attempt to lure nontraditional gamers to its Xbox 360 game console. While the Kinect was revolutionary in that it did away with the need for a controller, it has received a lukewarm reception in the gaming world. Turns out a score of buttons on a handheld controller is a pretty efficient way to navigate a console, albeit less physically entertaining.

The company faced backlash from the gaming community when it bundled sales of the Kinect v2 with the Xbox One, released last year. In June, Microsoft began selling the Xbox One sans Kinect in an attempt to compete with the PlayStation 4, which, at $400, has sold about 40 percent more units than the $500 Xbox-Kinect combo. The Xbox One now costs $400.

Responding to demand outside of the gaming universe, Microsoft created the Windows-enabled version of the Kinect v2 to help academics and software developers harness the technology’s nongaming potential. The PC version of Kinect came in response to the herd of software engineers that saw the value of the original Kinect and co-opted it by hacking the software themselves, according to Brian Bau, consumer technology analyst at Gartner, a market research firm.

Game developers have yet to produce a blockbuster hit, Bau said. In the meantime, Microsoft is trying to harness developer enthusiasm in nongaming fields.

“These tech developers have cool things in the labs and they don’t know how they are going to develop over time, but you look at user interfacing long term, and gesture has got to be a part of that,” Bau said. “The maker community — this is what it’s all about. Giving people the tools so that they can make cool things in the future.”

The company showcased some of the Kinect’s nongaming possibilities at the Microsoft Build Developer Conference in April. A medical software company in San Diego is using it to help physical therapists monitor patients remotely. The sensor is also helping surgeons manipulate computer screens without having to wash their hands and helping South Korea monitor the demilitarized zone it shares with North Korea.

In the South Bay, Kinect has added a new level of complexity to the parachute simulations that Systems Technology has been developing for the past 20 years.

Earlier Parasim modules consisted of a parachute harness attached to a metal frame. Jumpers would be strapped into the harness and hung in a horizontal free-fall position with a virtual reality headset covering their eyes. Before the Kinect was installed, jumpers could not manipulate the video game until deploying their chutes, which would swing them down into a vertical position and activate the chute’s steering toggles.

The parachute toggles were the only way to control the virtual environment, which meant the free-fall portion of the training was on autopilot.

By placing a Kinect sensor underneath the suspended jumper, a skydiver can now control his or her downward trajectory by shifting body angle.

“It’s a good initial effort,” said Systems Technology research engineer and veteran skydiver Amanda Lampton, who was brought in from another department to access the authenticity of the free-falling software.

The ability to change direction and speed in free fall is useful for training military personnel who jump out of planes in groups and have to scatter in the air before deploying their chutes.

“A wind tunnel is perfect for body positioning and learning how to maneuver and orient yourself, but you can’t do that last stage where you get ready and open your canopy and control it all the way to the ground,” said Cecy Pelz, senior specialist at Systems Technology. “Parasim bridges that gap.”

Despite the limitations of its clunky VR headset and the Nintendo 64-quality graphics, Parasim feels surprisingly real. It’s hard not to feel like a vertically challenged Peter Pan when strapped into the harness.

The experience will become even more immersive if the company adopts the highly anticipated Oculus Rift headset. The Irvine-based company, acquired by Facebook in March for $2 billion, is developing a prototype that is being celebrated as the new gold standard for virtual reality.

The device’s 180-degree field of vision is so immersive that “you feel like you’re going to fall off your chair if you’re not careful,” Pelz said.

The headset, which is not commercially available, would make Parasim a much more realistic experience without risk of injury, Pelz said.

“You’re strapped up. You’re not going to fall very far.”