Motion compensation for dynamic imaging

A ladar system for forming an image of a target, the system comprising:

• a pulsed laser transmitter configured to transmit a sequence of laser pulses;
• a camera comprising an array detector;
• a processing circuit;
• and a display, the camera and the processing circuit being together configured to form a plurality of point clouds, each point cloud corresponding to a respective transmitted laser pulse, each point in the point cloud corresponding to a point on a surface of the target, the processing circuit being configured to:
• group the plurality of point clouds into a plurality of point cloud groups according to a contiguous subset of the sequence of laser pulses, each of the point clouds of each group having an index;
• form a plurality of average point clouds, each of the average point clouds being the average of a respective group of the plurality of point cloud groups;
• form a first estimate of a six-dimensional velocity of the target, comprising three translational velocity components and three angular velocity components, from the plurality of average point clouds;
• and transform each of the point clouds of a first group of the plurality of point cloud groups, by a transformation proportional to the product of:
• the first estimate of the six-dimensional velocity, and the index of the point cloud within the first group of point clouds;
• form the image of the target from the transformed point clouds;
• and display the image of the target on the display.