ViseJoint virtual encoders

Camera-based angle sensors for sensorless control of smart robot arms

Explainer video Request demo

ViseJoint virtual encoders

Sensor principle visejoint Sensor principle visejoint
Purely camera-based robot control

ViseJoint is a virtual sensor based on computer vision software that measures angular positions of joints (virtual encoder). All axes of a robot arm are measured simply by looking at them with cameras. Positioning and control of robot arms works purely camera-based, even a robot arm without any hardware encoders is possible!

Learn more about camera-based sensor technology


Cameras: The essential robot sensor

ViseJoint relies on one or several standard cameras next to the robot arm. Smart service robots already use cameras for navigation, pose estimation or object/face detection. Now, those existing cameras are co-used for angular sensing! All data derived from the camera is naturally coherent, ensuring minimal relative positioning errors.


Simplified electronics and mechanics

ViseJoint enables sensorless robot arms, relying only on an external camera. Moreover, with external sensing, the true position of the arm is always known. Gear backlash, bending of the links or imprecise mounting no longer disturb positioning accuracy. Thus, camera-based sensing greatly simplifies the links, gears, sensors, electronics and wiring of a robot arm. Novel home applications or ultra low-cost robots become possible!

Contact us
Sensor principle visejoint

Use Cases

Benefits

Remote Sensing

Details An external, nearby or “eye-in-hand” camera observes the robot. This remote sensing approach avoids errors by decalibration and ensures results coherent with the outside world. Also, the camera is co-used for other tasks like object recognition and bin picking.

Virtual sensor

Details Sensor data are calculated virtually by a computer vision software, observing the robot with a camera. Electronic components and cabling required by standard hardware sensors are replaced with a software solution!

Simplified hardware

Details Camera-based sensing shifts hardware functionality to software, reducing the number of electronic sensors and their wiring. But there is more: External sensing captures the true state of the robot, including backlash and bending. Therefore, simplified and lighter mechanical components like gears and links can be used!

Packages and Solutions


Technical data

ViseJoint camera-based angular sensors(1)
Camera setup Many options, e.g. 2-3 cameras in workspace next to robot
Camera type Standard grayscale or RGB global shutter cameras
Relative positioning accuracy Up to 1 mm (2)
Measurement rate Typ. 60 Hz; 20 Hz to 120 Hz feasible (camera framerate)
Number of axes Unlimited; typ. 5 to 7 joints
Max. motion speed 1.5 m/s
Marker placement Flexible; typ. on base, end-effector, middle link
Interfaces and hardware
Camera interface USB3Vision, GigE Vision, UVC, any ROS camera
Software interface ROS (standardized incl. MoveIt, ROS Control); Customized
Software package Docker containers on Windows/Linux; Ubuntu package
Hardware requirements Standard PC with i5/i7 CPU; Various ARM platforms

(1): Camera-based sensing can be configured in many ways, adapted to your needs. For instance, a higher camera resolution and a zoom lens improve accuracy. Above, you find typical values with mid-range industrial cameras.
(2): The limiting factor is pose estimation of the object. Robot pose estimation is typically more accurate.

Contact

Visevi Robotics GmbH
in WERK1, Atelierstr. 29
81671 Munich, Germany