This device is intended to be operated with a multi-digit precision
grasp (like a pen) which makes it suitable for a large number of applications.
It is electrically actuated, and motion is transmitted to the distal joints
by stiff polymeric tendons. A second generation device, which has the characteristic
of being statically and dynamically balanced, has been developed by MPB
Technologies Inc., Montréal, in collaboration with McGill University.
Freedom-7 Haptic Interface
The design also provides for a scissor-like distal axis acting as the
7th degree of freedom. While a comprehensive set of performance figures
is being measured for future reference in improved versions, the following
figures stand for the current prototype. Workvolume: 120X180X160mm; Orientation:
90X100X120 degrees; Peak Force and Torque 5N and 300 Nmm; Displacements
resolution: 0.02 mm, angular resolution: 20 seconds of degrees; Resolvable
forces and torques at the handle: 0.01 N and 0.7 mNm; Electromechanical
bandwidth: 200 Hz in all directions; Inertia perceived by the user: less
than 100g. The use of advanced composite is also being researched by Prof.
Lessard for increased performance and manufacturability. A commercial version
is now marketed by MPB Technologies, Montréal.
Commercial Version of Freedom-6