Effect of virtual fixture compliance on human-machine cooperative manipulation

Formalizing Assistive Teleoperation

“…Since then, research on this topic has proposed a great variety of methods for assistance, ranging from the robot having full control over all or some aspect of the motion [1]- [6], [10], [11], to taking control (or releasing it) at some trigger [9], [13], [20], to never fully taking control [4], [6]- [8], [14]. For example, Debus et al [3] propose that the robot should be in full control of the orientation of a cylinder while the user is inserting it into a socket.…”

“…Virtual fixture-based methods (e.g. [6], [12]- [14]) that are commonly used to guide the user along a predefined path become blends of the user input with a policy that projects this input onto the path. The arbitration function dictates the intensity of the fixture at every step, corresponding to a normalized "stiffness/compliance" gain.…”

“…II) compared more manual vs. more autonomous assistance modes [4]- [6] with surprisingly conflicting results in terms of what users prefer. Rather than using autonomy as a factor, we introduce aggressiveness: arbitration should be moderated by the robot's confidence in the prediction, leading to a spectrum from very timid to very aggressive assistance, from small augmentation of user input even when confident to large augmentation even when unsure.…”

Position referenced force augmentation in teleoperated hydraulic manipulators operating under delayed and lossy networks: A pilot study

“…In an impedance-type virtual fixture scheme, the haptic force is proportional to the difference between the actual and desired positions at the slave end-effector, and its direction is orthogonal to the intended trajectory of the haptic device [30][31][32] . No information about the position of the slave is used in virtual fixture scheme.…”

Control of haptic interaction : an energy-based approach

“…proximity or navigation cues. Virtual fixtures as described by Abbott, Marayong and Okamura (2007) and Marayong et al (2002) are also a type of SCS.…”