Festo, inventor of amazingly lifelike, sophisticated and elegant robotic creatures -- dragonflies, birds, jellyfish, and penguins -- has done it again. The company's latest robotic achievement is the BionicKangaroo, which recovers and stores kinetic energy each time it jumps, and uses that energy on the next jump.
Unveiled at the Hannover Trade Fair in Germany earlier this month, the BionicKangaroo is one of many projects the company has pursued under the aegis of its Bionic Learning Network. Others introduced at the Fair are the DualWingGenerator, the MultiChoiceGripper, and the flying eMotionSpheres. The network's purpose is to use the energy-efficient principles already found in nature and adapt them to automation technology.
Get a closer look of Festo's BionicKangaroo by clicking on the photo below.
The robotic kangaroo uses its tail and feet to balance itself while standing. The tail also gives it balance when the robot jumps. Its angle is controlled by an electric servomotor. Two electric servomotors located between the hip and thigh control the robot's legs to move them forward and backward. The legs are actuated via two Festo DSNUP 20 pneumatic lightweight cylinders.
During two years of development, which included close study of the movements of real kangaroos, Festo's engineers found that when a real kangaroo jumps it harvests that kinetic energy and immediately uses it to power the next jump. This is done with the animal's unusually large Achilles tendon, emulated in the BionicKangaroo by a big rubber band. That rubber band, an artificial tendon, is attached to the back of the robot's foot, paralleling a pneumatic cylinder on the robot's knee joint. Each time the mechanical kangaroo lands after a jump, it is cushioned by that artificial tendon, which also absorbs the jump's kinetic energy, and then retrieves and releases it for the next jump.
The robot's design combines pneumatic and electrical drive technology, plus very precise controls and condition monitoring to help ensure stability during jumping and landing. Its pneumatics give it power to jump up to a height of 40 cm (15.7 inches) and a distance of 80 cm (31.49 inches). Electric motors are used for more precise positioning, such as controlling the robot's tail and hip movements. The BionicKangaroo can use two different types of mobile energy supply: one has an integrated compressor and the other has a high-pressure storage device. Both provide the needed compressed air with two of Festo's MHE2 solenoid valves. Electrical storage for the valves, the electric drives, and the integrated control system is provided by lithium polymer rechargeable batteries.
The robotic kangaroo uses its tail and feet to balance itself while standing. The tail also gives it balance when the robot jumps. Its angle is controlled by an electric servomotor. The robot's legs are controlled by two electric servomotors located between the hip and thigh, which move these forward and backward. The legs are actuated via two Festo DSNUP 20 pneumatic lightweight cylinders, one attached along each lower leg. Each knee and ankle joint is connected to the other with a positive kinematic device that interlinks movement sequences.
An operator controls the BionicKangaroo with gestures via a Myo armband. The armband detects the movements of the operator's arm muscles with EMG (electromyography) muscle activity sensors and an integrated position sensor. It sends those signals via Bluetooth to the robot's Festo CECC control system, which has Ethernet, CAN, RS232, RS485, digital IO, and IO link interfaces. Laser-sintered parts reinforced with carbon form the BionicKangaroo's movement apparatus, and its body shell is cut out of foam. This gives the artificial kangaroo a weight of only seven kg (15.4 lb). Its height sitting is 60 cm (23.6 inches). You can find detailed specs here.