Sensing in Soft Robotics

Abstract

Soft robotics is an exciting field of science and technology that enables robots to manipulate objects with human-like dexterity. Soft robots can handle delicate objects with care, access remote areas, and offer realistic feedback on their handling performance. However, increased dexterity and mechanical compliance of soft robots come with the need for accurate control of the position and shape of these robots. Therefore, soft robots must be equipped with sensors for better perception of their surroundings, location, force, temperature, shape, and other stimuli for effective usage. This review highlights recent progress in sensing feedback technologies for soft robotic applications. It begins with an introduction to actuation technologies and material selection in soft robotics, followed by an in-depth exploration of various types of sensors, their integration methods, and the benefits of multimodal sensing, signal processing, and control strategies. A short description of current market leaders in soft robotics is also included in the review to illustrate the growing demands of this technology. By examining the latest advancements in sensing feedback technologies for soft robots, this review aims to highlight the potential of soft robotics and inspire innovation in the field.

Architected Poly(ionic liquid) Composites with Spatially Programmable Mechanical Properties and Mixed Conductivity

“…One application domain for our EMB3D printed pIL composites is soft robotics, where multiscale, mechanically robust, and self-sensing structural materials can provide distributed tactile and proprioceptive sensing for pose prediction, contact force estimation, and more. 54 As a simple demonstration, we investigated the sensing capabilities of a 3 × 3 × 3 octet lattice (unit cell length = 7 mm) (Figure 5a). The high ionic conductivities of pILs make them suitable as soft sensors; deforming the pIL composite lattices leads to changes in resistance (e.g., during compression).…”

Artificial Neuron Devices

“…In the past few years, tremendous efforts have been put into making soft robotics as intelligent as human beings. 511 To achieve this, perception is one of the grand challenges that needs to be addressed for intelligent soft robotics, and artificial neuron devices could be the solution for this. For example, neurotransmitter transmission is a common process in the nervous system of biological creatures, which is of importance for information transmission and processing.…”

“…Soft robotics have been extensively explored due to their merits, such as safe interaction with human beings, better manipulation of delicate objects, and possibility to work in unstructured environments with more robustness. In the past few years, tremendous efforts have been put into making soft robotics as intelligent as human beings . To achieve this, perception is one of the grand challenges that needs to be addressed for intelligent soft robotics, and artificial neuron devices could be the solution for this.…”

“…Conventional robots offer advantages such as high operating speed, precise control, and ease of programming for intricate tasks. ,, However, these systems often lack adaptability in unstructured environments. ,, To mimic complete biological nervous systems, soft actuators have been introduced to emulate the functions of the motor and muscle systems. Soft actuators employ various responsive materials and mechanisms, including pneumatic, magnetic, thermal, or photoactuation, and electrical actuation. ,− Electrical actuation, in particular, has gained prominence due to its seamless integration into artificial systems. Ionic polymer–metal composite (IPMC) actuators, known as artificial muscles, operate under low voltages (<3 V) and offer advantages in integration compared to dielectric elastomer actuators (DEA), which require high kilovolt inputs. ,, However, IPMC actuators exhibit drawbacks such as slower response speeds and lower actuation strain (0.5–10%) compared to DEA (1–1000%). , Artificial systems have also explored biohybrid actuators, showcasing unique benefits such as self-healing, autonomous responses, and high energy efficiency. , These hybrid systems incorporate both nerve and muscle cells or tissues, and even organs including insect limbs or animal limbs. ,− This approach opens up possibilities for applications in biointerfaces, neuroprosthetics, and neurorehabilitation.…”

Recent developments in stretchable and flexible tactile sensors towards piezoresistive systems: A review

“…309 Apart from this, the development of soft robotics is also picking up pace, and it, too, requires its sensory system. 310 As titled, applications of the stretchable and flexible sensor in various domains. Application of stretchable and flexible sensors may be categorized into four sections: healthcare, human motion detection, human-robot interaction and automation, and soft robotics, as shown in Figure 17, and their details are discussed in Table 6.…”