Harvard University and Boston Children’s Hospital researchers have developed a customizable soft robot that fits around a heart and helps it beat, potentially opening new treatment options for people suffering from heart failure. The soft robotic sleeve twists and compresses in sync with a beating heart, augmenting cardiovascular functions weakened by heart failure. Unlike currently available devices that assist heart function, Harvard’s soft robotic sleeve does not directly contact blood. This reduces the risk of clotting and eliminates the need for a patient to take potentially dangerous blood thinning medications. The thin silicone sleeve uses soft pneumatic actuators placed around the heart to mimic the outer muscle layers of the mammalian heart. The device is tethered to an external pump, which uses air to power the soft actuators.