Figure 1: Squishymotor
A new soft motor was recently introduced that could drive a small squishy vehicle under water, over rough terrains without actually breaking a sweat. Aaron D. Mazzeo, the assistant professor from the Rutgers department of aerospace and mechanical engineering explains, “The introduction of a wheel-and-axle assembly in soft robotics should enable vast improvements in the manipulation and mobility of devices. We would very much like to continue developing soft motors for future applications and develop the science to understand the requirements that improve their performance.”
For creating this vehicle, Mazzeo’s team took silicone rubber that is a million times softer as compared to aluminum. The softness of this material falls somewhere between human calf muscle and silicone spatula. These motors were created with the help of 3D-printed molds as well as soft lithography. The team has finally registered for provisional patent of this design. Soft lithography is mostly used for micro to nano scale structures and it is called ‘soft’ in reference to the materials used by it. It also includes some elastomers like PDMS i.e. an organosilicon.
As per Mazzeo, this motor is a beautiful combination of several new innovations that includes offering torque without a single bend. Another collaborator of this research, a doctoral student from Rensselaer Polytechnic Institute, Xiangyu Gong further explains, “If you build a robot or vehicle with hard components, you have to have many sophisticated joints so the whole body can handle complex or rocky terrain. For us, the whole design is very simple, but it works very well because the whole body is soft and can negotiate complex terrain.” the varied applications of this soft motor would include search-and-rescue mission in harsh climatic conditions, better driving of amphibious vehicles that can easily reach to the other end of cracky lake beds, modification of objects during MRIs, and usage of shock-absorbing vehicles as landers with parachutes.