As an inseparable part of the control system of construction machinery and human-machine interface, Industrial joysticks are now widely used in many fields such as construction machinery, agricultural machinery and aerial work platform controlling.
There are three broad types of industrial joysticks currently used in industrial applications, broadly classified according to the control principle.
In most industries due to the mechanical joystick can not complete the complex analog action, logic control, has been gradually eliminated in the process of industrial upgrading in China, it is only used in some occasions requiring a very low cost.
Hydraulic joystick, can use a lower cost to control the flow of a hydraulic pilot valve, and with a controller for basic logic control, but correspondingly in some occasions, can not avoid the leakage of oil, hydraulic joystick can not be used in some high environmental requirements of the occasion.
Electric joystick has the advantages of stable electrical signal, editable, can handle complex operation logic and other advanced performance, it gradually becomes the trend of industrial upgrading applications.
Nowadays, the industries of excavator, agricultural machinery and mining machinery have gradually switched from hydraulic control to electric control system. The electronic control can do more complex logic system and security system, which has been applied in the aerial work truck industry where safety requirements are high for dozens of years. And the system of electric joystick can be used in many industries that require high clean environment, such as supermarket storage, video surveillance, medical and so on.
Usually the model selection is based on user's operating habits. More commonly asked for is the choice of Hall type joysticks and potentiometer joysticks.
hand grip joystick
Hall type joystick outputs analog voltage signal when there is an action, and uses the active output electrical signal to control the relay device to achieve weak power control strong power. In this case, the device being controlled is a power-using device and the terminals have no voltage. In addition, Hall type joystick is non-contact operation, with longer working life. Usually potentiometer type has a life of 1~ 2 million times, while Hall type can be 5 million times, or even higher. However, the Hall effect joystick needs power supply to complete the analog output, and it can not be used in a heavily polluted environment, especially in an environment with a lot of metal dust or strong external magnetism, the change of magnetic field will make the output of the joystick change or even fail.
Potentiometer type joystick outputs a switching signal without voltage when the action is output, such as normally open or normally closed, just like a switch output when a relay is closed. It is usually used for devices where the controlled voltage and the controlling voltage are of the same level. In this case, the device being controlled is a line and the terminals have voltage. However, the contact type is with better stability compared to Hall.
In general the working life of potentiometer joystick depends the life of the potentiometer itself, most quality potentiometers have a life of hundreds of thousands to a million times, some can reach 1~ 2 million times or even higher. It does not require additional power supply during use.
According to the above characteristics, the Hall type joystick is generally used for frequently operated equipment such as excavators and loaders. For mining machinery and other situations where metal dust may exist, or where there is electromagnetic interference, the potentiometer type electric joystick is recommended.
So, how to choose a joystick from a variety of types, is also determined by the availability of additional power supply on the client's system. Usually Hall's regular voltage is 3.3Vdc and 5Vdc, while the wide voltage version can do 9~36Vdc power supply.
There is also a bus type output form, which is generally used in applications that require bus communication. In general, the construction machinery industry uses CAN bus type more often. Other industries also use RS232, RS485, USB and other bus output forms. Customers need to choose according to their own operating conditions.
Finally, the application of spring reset type and friction positioning type.
Spring reset joystick suitable for operating at high frequency and need reset to the middle or starting position occasions. Usually applied in construction machinery, aerial work trucks, forklifts, etc.
Friction positioning joystick: suitable for operating at low frequency and needing to maintain positioning. It is usually selected for agricultural machinery, drilling rigs, mining and other machinery.