The Sherpa robot (codenamed â€˜BigDogâ€™) is supposedly the most advanced four-footed robot in the world. The project is funded by the Defense Advanced Research Projects Agency (DARPA) and is being developed in cooperation with other agencies and organizations. Other DARPA-funded robot projects include that of the tree-climbing robot.
The BigDog project aims to create a robot that could mimic animal movement, mechanics, control, and structure. The robot is being developed for the primary purpose of developing a robotic “pack mule” – a robot that can be used in a battlefield to carry heavy loads and go over rough terrain. Thus, this robot would function like a real animal that can carry the military unit’s supplies and ammunitions, although unlike real animals, the robot will not go hungry, become thirsty or get weary.
The Sherpa robot would be comparable to a small mule in terms of size. It is not overtly tall or heavy; in fact, it can be mistaken for a quite large dog. The robot has a two-stroke, single cylinder gasoline engine. This engine drives a hydraulic system that is housed in the robot’s steel frame.
The Sherpa robot also comes equipped with an inertial measurement unit (IMU) which, in unison with the robot’s fiber optic laser gyroscope and multiple accelerometers, makes for its precise and measured stride. Other on-board sensors monitor joint position, ground load, hydraulic pressure, engine temperature, oil temperature, and other status indicators.
A stereo camera is also to become part of the Sherpa robot’s computer systems. This, however, will only be fully functional in future implementations for terrain detection.
Field Use Features
The current Sherpa Robot prototype has the capability to move at over 5.5 kilometers per hour. It can climb moderate slopes and carry loads less than its own weight. It can also respond to outside forces; for instance, it can balance itself when kicked or hit. Its legs are designed in such a way that they are similar to an animalâ€™s and absorb shock with every step.
Planned Future Versions
The next implementation of the Sherpa Robot is planned to have an additional powered joint and should be able to go faster and climb steeper slopes. Additional sensors are also planned to be installed, and current, non-fully functional ones (such as the stereo camera) are slated for full implementation.
The robot’s developers are also planning to make BigDog more independent (the current version relies on human-issued commands, or will only follow a very simple path) in the future.