There are many types of feedback control mechanisms and each has its own strength and weakness (for lack of a better term) depending on your robot design or your environment. Since there always new types of sensors being developed, there are always going to be more variants of feedback control available since this relies on sensors in order to determine the state of an actuator. Some of the possible information that one may want to collect from the actuator could be: speed, position, torque, temperature, light, impact force etc. One type of feedback mechanism that has been in development for a very long time but is much less common then the others previously mentioned is haptic (touch) feedback.

We as humans have haptic sensors literally all over our bodies built right into our skin. Our brain uses the information from those sensors, such as temperature, pressure, vibration, location (where on your skin are you being touched) and texture (also wetness and pain). There are not many examples of haptic feedback currently in electronics; one obvious one is vibration (ex. A phone vibrating to say you have a new message or a game controller vibrating in an intense moment in their game) and the other less obvious would be temperature related (ex. Touching some electronics components to feel for temperature, if they are too hot it might mean they are shorted or malfunctioning if they are not normally like that).

With the advances in Virtual reality (VR) technology haptic feedback could be a big addition to that in order to better immerse the VR user into the video or software they are using. A great example of this was in a recent movie titled: Ready Player One. In this movie the protagonist,, Wade Watts wears a haptic feedback suit which allows him to feel pressure or impact forces that occurred inside the VR video game world. The movie was based off of a Science fiction novel titled: Ready Player One, written by author Ernest Cline (published in 2011).

In reality, another more practical use that I’m sure everyone would agree on would be in medicine, where surgeons could remotely “feel” their patient to better perform their work. In theory this surgery could even be completed using haptic feedback from the other side of the world, provided there was a good communication system. This idea could even be extended to allow amputees who now instead rely on prosthetics, to be able to feel.

New work and research is expanding on this topic every day, and I’m excited for the future on this front. If anyone else can think of any examples on this or has any other thoughts or links to articles that you would like to share, please add a comment. I'd love to hear it.