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Matching the rich multimodality of natural organisms, i.e., the ability to transition between crawling and swimming, walking and jumping, etc., represents a grand challenge in the fields of soft and bio‐inspired robotics. Here, a multimodal soft robot locomotion using highly compact and dynamic bistable soft actuators is achieved. These actuators are composed of a prestretched membrane sandwiched between two 3D printed frames with embedded shape memory alloy (SMA) coils. The actuator can swiftly transform between two oppositely curved states and generate a force of 0.3 N through a snap‐through instability that is triggered after 0.2 s of electrical activation with an input power of 21.1 ± 0.32W(i.e., electrical energy input of 4.22 ± 0.06J. The consistency and robustness of the snap‐through actuator response is experimentally validated through cyclical testing (580 cycles). The compact and fast‐responding properties of the soft bistable actuator allow it to be used as an artificial muscle for shape‐reconfigurable soft robots capable of multiple modes of SMA‐powered locomotion. This is demonstrated by creating three soft robots, including a reconfigurable amphibious robot that can walk on land and swim in water, a jumping robot (multimodal crawler) that can crawl and jump, and a caterpillar‐inspired rolling robot that can crawl and roll.

Liquid crystal elastomers (LCEs) have attracted tremendous interest as actuators for soft robotics due to their mechanical and shape memory properties. However, LCE actuators typically respond to thermal stimulation through active Joule heating and passive cooling, which make them difficult to control. In this work, LCEs are combined with soft, stretchable thermoelectrics to create transducers capable of electrically controlled actuation, active cooling, and thermal‐to‐electrical energy conversion. The thermoelectric layers are composed of semiconductors embedded within a 3D printed elastomer matrix and wired together with eutectic gallium–indium (EGaIn) liquid metal interconnects. This layer is covered on both sides with LCE, which alternately heats and cools to achieve cyclical bending actuation in response to voltage‐controlled Peltier activation. Moreover, the thermoelectric layer can harvest energy from thermal gradients between the two LCE layers through the Seebeck effect, allowing for regenerative energy harvesting. As demonstrations, first, closed‐loop control of the transducer is performed to rapidly track a changing actuator position. Second, a soft robotic walker that is capable of walking toward a heat source and harvesting energy is introduced. Lastly, phototropic‐inspired autonomous deflection of the limbs toward a heat source is shown, demonstrating an additional method to increase energy recuperation efficiency for soft systems.