Hydraulic system with coordinated multiple axis control of a machine member

A method for controlling movement of a member wherein an angle of the member with respect to a reference is alterable by a first actuator and a length of the member is alterable by a second actuator, the method comprises:

• producing a command which designates a desired velocity that a point on the member is to travel along a desired substantially straight line path, wherein producing the command comprises:
• (a) designating a first desired velocity that the point on the member is to travel along a first axis, and
• (b) designating a second desired velocity that the point on the member is to travel along a second axis that is orthogonal to the first axis;
• transforming the command into a desired angular velocity and a desired length velocity for the member, wherein transforming the command utilizes the relationships defined by the equations:
• {dot over (X)}=cos(θ+γ){dot over (L)}+(−L sin(θ+γ)+d cos(θ+γ))({dot over (θ)}+{dot over (γ)})
• {dot over (Y)}=sin(θ+γ){dot over (L)}+(L cos(θ+γ)+d sin(θ+γ))({dot over (θ)}+{dot over (γ)})
• where {dot over (X)} is velocity of the point on the member along the first axis, {dot over (Y)} is velocity of the point on the member along the second axis, θ is the angle of the member, {dot over (θ)} is the angular velocity of the member, γ is a pitch angle of a machine on which the member is mounted, {dot over (γ)} is an angular pitch velocity of the machine, {dot over (L)} is a rate at which the length of the member is changing, and d is a distance that the point is offset from a longitudinal axis of the member;
• converting the desired angular velocity for the member into a desired first velocity of the first actuator;
• operating the first actuator in response to the desired first velocity to alter the angle of the member;
• and
• operating the second actuator based on the desired length velocity to alter the length of the member.

A method for controlling movement of a member wherein an angle of the member with respect to a reference is alterable by a first actuator and a length of the member is alterable by a second actuator, the method comprises:

• producing a command which designates a desired velocity that a point on the member is to travel along a desired substantially straight line path;
• sensing a first parameter of the machine to produce a first signal denoting the angle of the member relative to a reference, wherein sensing a first parameter senses a dimension of the first actuator;
• sensing a second parameter of the machine to produce a second signal denoting the length of the member;
• deriving an actual angular velocity of the member from the first signal;
• and
• deriving an actual length velocity of the member from the second signal;
• transforming the command into a desired angular velocity and a desired length velocity for the member;
• converting the desired angular velocity for the member into a desired first velocity of the first actuator;
• operating the first actuator in response to the desired first velocity to alter the angle of the member;
• and
• operating the second actuator based on the desired length velocity to alter the length of the member.

A method for controlling movement of a member, wherein an angle of the member with respect to a reference is alterable by a first actuator and the member has a first section that extends from a second section by an amount that is varied by a second actuator, the method comprises:

• designating a first desired velocity that a point on the member is to travel along a first axis;
• designating a second desired velocity that a point on the member is to travel along a second axis which is orthogonal to the first axis;
• sensing a first parameter that indicates a position of the member;
• deriving an angular position of the member from the first parameter;
• sensing a second parameter that indicates an amount that the first section extends from the second section, wherein sensing a second parameter comprises sensing a dimension of the second actuator;
• deriving a length of the member from the second parameter;
• transforming the first and second desired velocities into a desired angular velocity and a desired length velocity for the member, wherein that transforming is based on the angular position and the length of the member;
• converting the desired angular velocity for the member into a desired first velocity of the first actuator;
• operating the first actuator in response to the desired first velocity to alter the angle of the member;
• and
• operating the second actuator based on the desired length velocity to alter the length of the member.