The workshop uses a casting manipulator to save labor costs
In order to grasp objects at any position and orientation in space,6 degrees of freedom are required.The degree of freedom is the key parameter of manipulator design.The more degrees of freedom,the greater the flexibility and versatility of the manipulator,and the more complex its structure.Generally,the manipulator has 2~3 degrees of freedom.The control system controls the motor of each degree of freedom of the manipulator to complete specific actions.At the same time,the feedback information from the sensor is received to form a stable closed-loop control.The core of the control system is usually composed of microcontroller or dsp and other micro control chips.
Its drive system is usually composed of cylinders,air valves,air tanks and air compressors.It is characterized by convenient air supply,rapid action,simple structure,low cost and convenient maintenance.However,it is difficult to control the speed,and the air pressure cannot be too high,so the snatching capacity is low.
The control system can be designed to adopt digital sequence control according to the action requirements.It needs to prepare a program for storage,and then according to the specified program,the storage mode of controlling the manipulator to carry out the working program includes separate storage and centralized storage.Separate storage is to store the information of various control factors in two or more storage devices respectively,such as the sequence information is stored in the latch plate,cam drum and perforated belt;Position information is stored in time relay,constant speed rotary drum,etc;Centralized storage is to store all the information of various control factors in a storage device,such as tape,magnetic drum,etc.This method is used for simultaneous control of sequence,position,time,speed,etc.,that is,continuous control.
The elements of manipulator control include working sequence,arriving position,action time,motion speed,acceleration and deceleration,etc.Manipulator control is divided into point control and continuous trajectory control.
The latch plate is used in the situation where the program needs to be changed quickly.To change a program,you only need to replace a pin plate,and the same plug-in can be used repeatedly;The program length contained by the perforated tape can be unlimited,but if there is an error,it should be replaced completely;The information capacity of the perforated card is limited,but it is easy to replace,save and reuse;The magnetic core and magnetic drum are only suitable for occasions with large storage capacity.As for which control element to choose,it is determined according to the complex program and program of action.For the manipulators with complex movements,a learning and reproducing control system is adopted.More complex manipulators are systems controlled by digital control systems,minicomputers or microprocessors.The control system is mainly used for latch plate,followed by cam drum.It is equipped with many cams,each of which is assigned to a moving shaft,and the drum will complete a cycle in one cycle.
