Geometric control envelope system and method for limiting commands to actuator mapping function

A vehicle comprising:

• a chassis;
• a plurality of propulsion mechanisms configured to propel the chassis;
• and
• a processor configured to:
• generate a geometric control envelope in a geometric space of operation points defined by a plurality of control aspects, the geometric control envelope having vertices representing maximum values of the control aspects such that operation points outside the geometric control envelope represent operational conditions unattainable by a plurality of propulsion mechanisms of the vehicle and operation points in the geometric control envelope represent operational conditions attainable by the plurality of propulsion mechanisms;
• determine a desired operation point in the geometric space representing a control input;
• determine whether the desired operation point is in the geometric control envelope;
• if the desired operation point is in the geometric control envelope, instruct the plurality of propulsion mechanisms to propel the vehicle according to the desired operation point;
• and
• if the desired operation point is outside the geometric control envelope,
• scale up a first one of the control aspects by a first factor;
• determine an effective operation point in the geometric control envelope geometrically closest to the desired operation point;
• scale down all of the control aspects by a second factor inverse of the first factor;
• and
• instruct the plurality of propulsion mechanisms to propel the vehicle according to the effective operation point.

A method of controlling a vehicle, the method comprising, via a processor of the vehicle:

• receiving a flight command;
• generating a wedge-pyramid geometric control envelope in a geometric space of operation points defined by tilt, yaw, thrust, and tilt axis angle, the geometric control envelope having vertices representing maximum values of the tilt and yaw, and a face representing maximum values of the thrust, such that operation points outside the geometric control envelope represent operational conditions unattainable by four propulsion mechanisms of the vehicle and operation points in the geometric control envelope represent operational conditions attainable by the four propulsion mechanisms;
• determining a desired operation point in the geometric space corresponding to the flight command;
• determining whether the desired operation point is in the geometric control envelope;
• if the desired operation point is in the geometric control envelope, instructing the plurality of propulsion mechanisms to propel the vehicle according to the desired operation point;
• and
• if the desired operation point is outside the geometric control envelope,
• scaling up a first one of the control aspects by a first factor;
• determining an effective operation point in the geometric control envelope geometrically closest to the desired operation point;
• scaling down all of the control aspects by a second factor inverse of the first factor;
• and
• instructing the plurality of propulsion mechanisms to propel the vehicle according to the effective operation point.