Hippotherapy is an effective form of rehabilitative treatment, especially as a means of improving coordination, balance and strength. But this equine-assisted therapy is not available to those without access to a real horse.
Rice University students have designed a suitable substitute: Stewie the robotic horse. The robotic system is said to be more comfortable and controllable for riders and could help patients with neurological and movement 
Rice University students presented their version of a mechanical horse for hippotherapy at the George R. Brown Engineering Design Showcase, where they won an Excellence in Capstone Engineering Design Award. Source: Jeff Fitlowdisorders.
Engineered in accordance with the Stewart platform robotic concept invented in the 1950s, Stewie uses computer-controlled motors attached to each of six aluminum legs, giving the saddle free movement in six degrees: latitude, longitude, vertical, pitch, roll and yaw. A computer manipulates the motors, which allows the students to tweak the saddle movements so they match those of an actual horse.
An inexpensive app was used to collect equine movement data by taping a smartphone to the back of a saddle. The information is loaded into a small control panel that can be used by patients and therapists to choose a horse and define session length.
The simulated steed is designed to hold the weight of a 250-pound rider, and an additional saddle that is adaptable for riders with different physical builds is available.
The schematics and code developed by the researchers are open-source and will be online and free to anyone who wants to replicate or improve upon their design.
