An electrically-operated gripper hand has three identical, double-jointed fingers, two of which can be reconfigured with coupled movement at the base by 90 deg in opposing directions.'Intelligent' gripper uses three fingers An electrically-operated gripper hand has three identical, double-jointed fingers, two of which can be reconfigured with coupled movement at the base by 90 deg in opposing directions. Schunk has now launched its new electrically-operated three-finger gripper hand, the Schunk Dextrous Hand (SDH). Equipped with three identical, double-jointed fingers, the SDH has two fingers that can be reconfigured with coupled movement at the base by 90 deg in opposing directions.
Localised contact forces are registered and transmitted back to the controls by means of six tactile sensor fields on the grip surfaces that enable object recognition as well as a delicate, tactile and secure gripping process.
The seven independent movement joints of the SDH enable performance of the industrial gripping types of 'three-finger centric', 'two-finger parallel' or 'cylindrical grip' plus many further types of gripping.
The intelligence of the SDH lies in the base of the hand as the control strategies for the different grip scenarios can be loaded into the memory of the hand's electronics as a decentralised programme module.
The SDH concept is aimed particularly at the use of the hand in difficult industrial environments.
The thre-finger hand fulfils many important requirements in this respect and it can be programmed for different workpieces as well as a family of parts.
Using the optional tactile sensor system for pressure and surface recognition, the hand can detect whether a sensitive object has been gripped in the best way or whether the grip needs to be corrected (reactive gripping).
Depending on the object and interaction with people, the joint modules of the SDH can generate torques of up to 4.8Nm for the proximal joint module and 2.1Nm for the distal joint module, which almost corresponds to the strength of the human hand.
For the SDH to be able to master the cylindrical grip as well as the parallel and centric grip, two of the fingers can be angled towards each other.
This allows the SDH to grip cylindrical objects securely.
So that the SDH maintains a secure grip even under rough operating conditions, all the linkage areas and joints are statically or dynamically sealed to protect against dust and moisture.
The SDH offers a high level of safety when interacting with man and machine.
The hand has no corners or sharp edges and the wiring is securely protected within the sealed fingers by special rotating guides.
Gripping speed and force can be programmed depending on the task or processing in question so that gripping presents no dangers.
If a finger nevertheless encounters an obstacle, the drives within the hand detect the increased power consumption generated within milliseconds.
In order to meet the demands of the rapidly growing market for mobile industrial and service robotics, the power supply of the SDH is designed for 24V DC.
The intelligent components in the base of the hand also make the three-finger hand a versatile robotic component to control.
The function and mobility of the fingers have deliberately been designed in a modular way to enable integration with individual models in future and secondly to produce unit cost benefits by covering different robot types and gripping tasks with the same components.
The design of the SDH therefore complies fully with the Schunk philosophy: 'from the individual module to the complex robot structure'