Proportional. The closing speed is determined by the speed and amount of the muscle relaxation.
Closing:
By very slow muscle relaxation to the electrode, the hand stops in an opened position.
Stopping:
Electrode 2:
The level of the muscle signal to the second electrode determines the build-up of the grip
Grasping:
force.
Example 1: After opening the hand, the patient relaxes the muscle at any speed. The hand closes propor-
tionally to the speed of the muscle relaxation. The object is grasped with minimal force.
Example 2: After grasping as described in example 1, the hand shall grasp the object with a higher grip
force. For this purpose, the amputee must create an electrode signal to the second electrode.
Proportionally, a grip force of up to approx. 100 N can be built up.
Control Mode 4: VarioDual: Two electrodes
Opening
Increasing electrode signal through muscle contrac-
tion to the first electrode
Speed: Proportional
Control Mode 5: DigitalControl
Requires: 2 electrodes,
1 electrode and 1 switch or
1 switch
The hand closes at constant speed, and the grip force increases proportionally to the duration of gripping.
Control with two electrodes
Digital. Controlled by the OPENING electrode. The hand opens at constant speed.
Opening:
Digital. Controlled by the CLOSING electrode. The hand closes at constant speed.
Closing:
Control Mode 5: DigitalControl: Two electrodes
Opening
Sustained electrode signal
Speed: Constant
Control with one electrode and one switch
Electrode signal to the OPENING electrode.
Opening:
Signal from the switch The hand closes at constant speed.
Closing:
38 | Ottobock
Closing
Declining electrode signal through muscle relaxation
to the first electrode
Grip force: Proportional to the signal strength to the
second electrode
Gripping once more with maximum force to the 2nd
electrode prevents the hand from opening due to
unintentional electrode signals.
Speed: Proportional
Closing
Sustained electrode signal
Grip force: Depends on the duration of the signal
Speed: Constant