Core Viewpoint - The article discusses the evolution of skeletal muscle tissue engineering from medical needs to a key technology driving the development of biorobotics, highlighting its potential in both medical applications and robotics [1][2]. Group 1: Medical Needs and Challenges - Skeletal muscle constitutes over 40% of body weight and is essential for movement. Loss of more than 15%-20% of muscle can lead to permanent functional loss [4]. - Current treatment options primarily rely on autologous muscle transplantation, which has limitations such as donor site availability, significant surgical trauma, and suboptimal functional recovery [4]. Group 2: Development of Skeletal Muscle Tissue Engineering - Clinical needs have propelled the development of skeletal muscle tissue engineering, aiming to cultivate functional muscle tissue in vitro for repairing large muscle defects [5]. - Researchers discovered broader applications in biorobotics, as engineered muscle offers unique advantages such as high mechanical compliance, energy efficiency, and fine motor control [5]. Group 3: Key Strategies in Muscle Tissue Engineering - The core strategies in skeletal muscle tissue engineering include scaffold design, cell sourcing, external stimulation, and bioreactor technology, all of which are continuously innovating [5]. Group 4: Scaffold and Cell Selection - Scaffolds provide three-dimensional support for cell growth and must meet strict requirements such as biocompatibility, degradation rate matching tissue regeneration, and hardness close to natural muscle (10-20 kPa) [6]. - Various materials are explored, including synthetic polymers like PCL and PLGA, and natural materials like fibrin and collagen. Innovative approaches include using decellularized plant tissues as scaffolds [6]. - In cell selection, satellite cells are the best for differentiation but are difficult to obtain, while mesenchymal stem cells are easier to acquire but have limited differentiation potential [7]. Group 5: Stimulation and Cultivation Techniques - To make engineered muscle functional, it is essential to simulate physiological environments and provide appropriate stimulation signals, including mechanical, electrical, and biochemical stimuli [8]. - Mechanical stimulation is crucial, with optimal substrate hardness (8-11 kPa) and dynamic stretching (35% strain rate) promoting muscle fiber alignment and maturation [8]. - Electrical stimulation mimics motor neuron activation, significantly increasing muscle contraction force by three times through intermittent stimulation [8]. Group 6: Biorobotics and Muscle-Driven Robots - The integration of skeletal muscle tissue engineering with robotics has led to the emergence of biohybrid robots, which utilize engineered muscle tissue as actuators, offering advantages over traditional motors [12]. - These muscle actuators allow for fine control, inherent compliance, and the potential for self-repair and adaptive growth [12]. - Various proof-of-concept muscle-driven robots have been developed, including a notable 18 cm tall biohybrid hand capable of selective finger movement [13]. Group 7: Future Prospects - The future of skeletal muscle tissue engineering is promising, with potential applications in personalized tissue transplantation for muscle loss patients, new soft actuator systems in robotics, and other fields like cultured meat production and drug screening [14]. - This interdisciplinary field combines insights from biology, engineering, and materials science, generating valuable new knowledge and innovations [14].