Treebot

Treebot has a pair of omni-directional tree grippers that enable the robot to adhere on a wide variety of trees with a wide range of gripping curvature. Treebot is able to change a moving direction in three dimensional space by bending the continuum manipulator.
The robot can maneuver on a complex tree environment, but only five actuators are used in the robots mechanism. 

The main structure of Treebot consists of two parts: an omni-directional tree gripper and a continuum manipulator. Two grippers are connected to the ends of the continuum manipulator. The grippers can grab a tree surface while the continuum manipulator acts as maneuver mechanism to move another end of the gripper to the next position.

The gripper is made of four claws equally separated by 90 degrees. Each claw is formed by two parts and has surgical needles installed at the tip. The sticky force of the gripper is generated by the spine
penetration. All claws in a gripper are actuated by a motor. A pushing plate is mounted at the end of the motor. When the motor extends, the plate pushes all the phalanges and makes them  move upward.
The special design of the gripper permits zero energy consumption in static gripping.