It’s the story of a long dynasty of industrial machines and robots. Crane machines or delta’s three arms began by packaging chocolates, before being used in watchmaking, tele-surgery and the processing of materials. They are mostly used as pick and place functions. Crane vending machines are also popular in public areas such as supermarkets. After paying some money, the machine is enabled, and the player is allowed to move the gripper using a joystick controller to try and catch a doll within a certain time.
Recently, the magnetoelectronics lab (meLAB) at the School of Engineering of the University of Glasgow developed a completely different crane machine for new students in their School Open Day to inspire them and spark their interest in engineering.
Instead of joystick control, the gripper of this machine is controlled by moving gesture. Firstly, the gripper installed on a delta robot will follow the 3-dimentional movement of the identified human hand. Also, the gripper folds when the controller's palm is closed. The gripper is released when the palm opens. In this way, for example, the experiences of gamers can be greatly improved.
This machine is based on a delta robot structure, a 3D camera and a microcontroller. The mechanical structure was designed according to the specific requirements of gesture control and crane machines. To find the position of hand and gesture, a Microsoft Kinect is employed as 3D camera. Kinect (codenamed Project Natal during development) is a line of motion sensing input devices by Microsoft for Xbox 360 and Xbox One video game consoles and Windows PCs. It is programmable and able to trace the movement of humans. After collecting the gesture data by Kinect, the motors on the delta robot can be controlled accordingly. For example, the gesture position will be calculated into the angles of three motors on a static platform by an inverse kinematics algorithm. Additionally, the control of the other peripheral devices, such as the coin collector, should also be included in the microcontroller.
The researchers at meLAB aim to improve the degree of freedom (DOF) in such gesture controlled delta robots using magnetic levitation. As future work, they will develop general methods for cognitive surgical robots capable of combining sensing, dexterity and cognitive capabilities to carry out simple surgical actions autonomously, such as puncturing, cutting and suturing.
More info: www.gla.ac.uk/melab