TACTIP, Tactile fingertip for robot hands
The sense of touch
We use our sense of touch to interact with each other and with our environment. It has been said that of all the senses, if lost, touch has the most detrimental effect on a person’s quality of life. With the absence of a tactile sense, humans are no longer able to control objects, or even their own limbs, without significant visual feedback and effort, as well as losing the ability to meaningfully interact and communicate with each other physically. The sense of touch is an essential part of autonomous independent existence and has a significant role in emotional interaction between humans.
The mechanics of the fingertip skin, on both the macro and micro scale, have vital and often overlooked roles to play in our sense of touch. By exploiting some key features of the skin we aim to gain new tactile sensor designs that have the same high compliance needed to be highly sensitive and detailed tactile sensors and strength to be capable and versatile gripping and manipulating tools.
There is growing interest and need to place robots in the workplace along side humans. For robots to function effectively in these environments, they need to be able to perform the same complex functions of sensing and manipulation as humans. Traditional industrial grippers equipped with contact and pressure sensors are not capable of the diverse tasks humans undertake, where objects have different sizes and require a wide range of pressures and grips. A compliant sensing gripper, such as the human fingertip, is far more attractive.
The TACTIP device is a biologically-inspired sensing device, based upon the deformation of the epidermal layers of the human skin. In particular the relationship between the papillae ridges/pins that form between the dermis and epidermis regions of the skin and the Pacinian corpuscle and Meissners corpuscle mechanoreceptors.
Deformation from device-object interaction is measured optically by tracking the movement of internal artificial papillae pins on the inside of the device skin. These papillae pins are representative of the intermediate epidermal ridges of the skin.
The TACTIP device is capable of sensing pressure force, shear force, surface strain for detecting edges, and texture. The novelty of the TACTIP resides in the raised three dimensional papillae pins and optical tracking of their free movement.
Typical robotic hand gripping activities require compliant contact surfaces, the fingertip and palm, coupled with good force sensing capabilities. The TACTIP offers both of these attributes in one device.
The TACTIP has gone through a number of development stages from large scale prototype, through to its latest miniaturised state ready for installation on a robot or prosthetic hand.
- Prof. Sanja
Tel: +44 (0) 117 32 81301
Bristol Robotics Laboratory
University of the West of England
Bristol, BS16 1QD
Telephone: +44 (0)117 32 86798
- Prof. Chris Melhuish
- Prof. Tony Pipe
- Benjamin Winstone
- Gareth Griffiths
- Alex Sleat