Whole-Body Control

Whole-body controllers solve for joint configurations that satisfy multiple simultaneous objectives and constraints. The controller formulates an optimization problem: achieve desired hand position, maintain balance, avoid joint limits, minimize energy, respect torque limits. Quadratic programming or other optimization techniques solve for joint torques or positions that best satisfy all requirements. The controller runs at high frequency (100-1000 Hz), continuously recomputing solutions as objectives change. Hierarchical approaches prioritize critical constraints (balance) over secondary goals (hand precision). The result is coordinated motion where all body parts work together - leaning the torso to counterbalance arm extension, adjusting stance leg position during reaching.

Whole-body control enables humanoid robots to manipulate objects overhead while maintaining stable balance. Reaching tasks adjust the entire body posture to extend workspace. Bimanual manipulation coordinates both arms while keeping the torso stable. Walking while carrying asymmetric loads requires continuous whole-body balance adjustment. Crouching to pick up floor-level objects coordinates legs, back, and arms. Push recovery engages legs, hips, and arms simultaneously. Dynamic tasks like throwing involve sequential whole-body coordination. Multi-contact scenarios like climbing stairs or ladders require full-body planning.