Design of mathematical models of muscle-like HASEL actuators from the perspective of biological muscle models and integration of these mathematical models in simulation and control frameworks of biological movement systems. With this, simulations of hybrid muscle systems can be performed, where artificial muscles are coupled with the biological system, e.g., to optimize the design of wearable assistive devices or prosthetics. Additionally, novel designs of artificial muscle-like actuators are investigated to approach the dynamics of biological muscles, which includes research in materials and fabrication methods for artificial tendons.