Figure 7
From: Contribution of interaction force to the sense of hand ownership and the sense of hand agency
Experimental setups. (A) The experimental setup of Study I consists of a robotic finger manipulandum controlled with LabVIEW via a USB data acquisition card. The device is placed over the abdomen of the participant on a support structure. The right hand of the subject rests on a wooden block. The participant wears a head-mounted display (not shown). The robotic device allows performing a pinching movement either actively or passively by moving the index finger against the thumb. It is composed of a fixed thumb socket, a moveable index finger socket attached to a linear rail, a motor to actuate the index finger socket via a cable/pulley transmission, an angular position encoder and a force sensor. (B) A virtual environment displays an avatar performing a pinching movement. The synchrony (synchronous vs asynchronous) and the congruency (left vs right virtual hand moving) can be manipulated under computer control. (C) Examples of position and force traces for an active trial (i.e. the subject moves) and a passive trial (i.e. the robot moves). (D) The experimental setup of Study II consisted of an MR-compatible robot controlled with LabVIEW. The output of the device is attached to the scanner bed with an adjustable mount. The forearm of the subject rests on foam pads. The participant wears MR-compatible goggles (not shown). The robotic device is equipped with a fiber-optic force sensor and an electro-optical encoder, and allows performing a pinching movement either actively or passively by moving the index finger against the thumb. A DC motor actuates a linear drive through a spindle, to which a hydraulic piston was fixed and remotely controlled the slave module inside the scanner room through a hydrostatic transmission. (E) A virtual environment displays an avatar performing a pinching movement. The synchrony (synchronous vs asynchronous) and the congruency (left vs right virtual hand moving) can be manipulated under computer control. (F) Examples of position and force traces for an active trial (i.e. the subject moves) and a passive trial (i.e. the robot moves).
