Excavation system having velocity based work tool shake

A method of controlling a machine having a work tool, comprising:

• sensing a parameter indicative of a load exerted on the work tool;
• detecting engagement of the work tool with a material pile based on the parameter;
• operating the work tool to load the work tool with an amount of material;
• determining whether loading of the work tool has been completed;
• lifting the work tool above a ground surface, using a lift actuator of the machine, when the loading has been completed;
• shaking the work tool based on a tilt velocity of the work tool with respect to a threshold velocity, using a tilt actuator of the machine;
• and
• causing the machine to withdraw from the material pile after shaking the work tool.

A machine, comprising:

• a frame;
• a plurality of wheels rotatably connected to the frame and configured to support the frame
• a power source mounted to the frame and configured to drive the plurality of wheels;
• a work tool operatively connected to the frame, driven by the power source, and having a tip configured to engage a material pile;
• a lift actuator configured to lift the work tool above a ground surface;
• a tilt actuator configured to tilt the work tool;
• a speed sensor associated with the plurality of wheels and configured to generate a first signal indicative of a travel speed of the machine;
• a torque sensor associated with the power source and configured to generate a second signal indicative of a torque output of the power source;
• an acceleration sensor configured to generate a third signal indicative of an acceleration of the machine;
• and
• a controller in communication with the speed sensor, the torque sensor, and the acceleration sensor, the controller being configured to:
• detect engagement of the work tool with the material pile based on at least one of the first, second, and third signals;
• operate the work tool to load the work tool with an amount of material;
• determine whether loading of the work tool has been completed;
• lift the work tool, using the lift actuator, when the loading has been completed;
• monitor a length of extension of the lift actuator, wherein a target length ranges from 15% to 20% of a maximum length of extension of the lift actuator;
• stop lifting the work tool when the length of extension reaches the target length;
• perform a first rack of the work tool;
• monitor a tilt velocity;
• and
• perform a first unrack of the work tool, when the tilt velocity is less than a threshold velocity;
• monitor a tip angle of the work tool while performing the first unrack of the work tool;
• and
• perform a second rack of the work tool when the tip angle is equal to a target tip angle.