Ghost Minitaur is a medium-sized legged robot platform. Its high-torque brushless outrunner motors and specialized leg design let this machine run and jump over difficult terrain. High-speed and high-resolution encoders let the machine see the ground through the motors and adapt faster than the blink of an eye, Jiren Parikh, CEO of its manufacturer, Ghost Robotics, says it can even clamber up trees.
The current version of Minitaur weighs 6 kilograms and can crawl, sidle crabwise or rear up against a vertical surface just like an excitable dog to reach high objects. Attachments on the end of the robot’s legs allow it to open door handles as well as to grip and climb fences. Its maximum speed in a springy running mode is 2 metres a second.
The springy gait is closely linked to one of Minitaur’s main design features: it is powered by direct drive and so has no gearing. This allows the motors to act as sensors, letting it feel its way over obstacles. The motor also acts like a spring-damper system so, even though the legs are rigid, the robot is bouncy.
“You can adjust the level of springiness by tweaking the software,” says Parikh.
The electronics are all built using off-the-shelf components, such as Arduino processors. This means that, although each robot currently costs around $10,000 to make, this should drop below $1500 when production ramps up. Similar existing robots can cost tens or hundreds of thousands of dollars.
Parikh hopes the robots could also prove useful to the emergency services. “In a disaster or search-and-recovery situation, we can send in hundreds of Minitaurs,” he says.
And along with customers involved in robotics research, the firm also has customers in the US military who are likely to be interested in Minitaur as a sensor platform for bomb disposal and urban reconnaissance, Parikh says.