Velocity based electronic control system for operating hydraulic equipment

A control apparatus for operating a hydraulic system having a pump which forces fluid from a tank into a supply line connected to a plurality of hydraulic functions, each hydraulic function including a valve assembly which controls flow of the fluid between the supply line and an actuator and between the actuator and the tank, the control apparatus comprising:

• a user input assembly which for each function generates an input signal indicating desired movement of the actuator associated with that function;
• a mapping routine which converts each input signal into a velocity command designating a desired velocity for the associated actuator, thereby producing a plurality of velocity commands;
• a flow sharing routine which alters the plurality of velocity commands when the aggregate flow being demanded by the plurality of functions exceeds the total flow available from the supply line;
• a valve opening routine which converts each velocity command into a set of valve flow coefficients each of which characterizes fluid flow through a valve of the valve assembly, and from the set of valve flow coefficients produces a set of control signals designating levels of electric current to apply to the valve assembly of the respective function;
• and
• a plurality of valve drivers which apply electric current to valves within each valve assembly in response to the respective set of control signals.

An apparatus for controlling a hydraulic system having a pump which forces fluid from a tank into a supply line connected to a hydraulic function, the hydraulic function including a valve assembly which controls flow of the fluid between the supply line and an actuator and between the actuator and the tank, the apparatus comprising:

• a user input device which generates an input signal indicating desired movement of the actuator;
• a system controller connected to the user input device and converting the input signal into a velocity command designating a desired velocity for the actuator;
• and
• a function controller connected to the system controller and converting the velocity command into a set of valve flow coefficients each of which characterizes fluid flow through a valve of the valve assembly, the function controller using each flow coefficient to produce a separate control signal which designates a magnitude of electric current to apply to a valve within the valve assembly.

A control apparatus for operating a hydraulic system having a pump which forces fluid from a tank into a supply line connected to a plurality of hydraulic functions, each hydraulic function including a valve assembly which controls flow of the fluid between the supply line and an actuator and between the actuator and the tank, the control apparatus comprising:

• a user input assembly which generates an input signal indicating a desired motion to be produced by the hydraulic system;
• a mapping routine which converts the input signal into commands designating desired movement for actuators associated with the plurality of the hydraulic functions, thereby producing a plurality of commands;
• a flow sharing routine which alters the plurality of commands when the aggregate flow being demanded by the plurality of functions exceeds the total flow available from the supply line;
• a valve opening routine which converts each command into a set of valve flow coefficients each of which characterizes fluid flow through a valve of the valve assembly, and from the set of valve flow coefficients produces a set of control signals designating levels of electric current to apply to the valve assembly of the respective function;
• and
• a plurality of valve drivers which apply electric current to valves within each valve assembly in response to the respective set of control signals.