Scenarios

PUSHING 1: Pushing with no contact force cost weight=0.  With no cost weight, the pushing only emerges due to the reference pose tracking of the left foot. The left foot barely touches the ground, only contributing to a slight velocity gain. The task eventually fails, as instability causes the planner to deviate from the reference pose.

PUSHING 2: Moderate pushing, with the contact force cost weight=300. The contact force cost causes a forward-pushing motion, contributing to the velocity gain on the board.  The board's orientation also stays more towards the initial orientation, as the pose gets more upright due to the pushes.

PUSHING 3: High contact force cost weight=600. The becomes seemingly instabile, causing early failures at half of the test runs. The trade-off between velocity gain and instability is notable with this high weight value.

PUSHING 4: Too high contact force  cost weight=1000. Too much emphasis on the pushing causes the humanoid to stumble over and fall after a few pushes.

STEERING 1: Steering with minimal pose-tilting ratio(=0.05). 

STEERING 2: Steering with optimal pose-tilting ratio(=0.2), found through the experimentation.

STEERING 3: Steering with high pose-tilting ratio(= 0.45). 

STEERING 4: Steep steering by forcing a maximised board angle.

GOALS 1: Steering to changing goal positions with fairly easy variation. 

GOALS 2: Steering to changing goal positions.

GOAL ORIENTATION 1: When goal orientation is over-emphasized, the planner greedily tilts the angle and ignores the board mechanics. In these experiments, the arms are not regulated  in anyway, causing them to flail around in uncontrolled manner. 

GOAL ORIENTATION 2: over-emphasized goal orientation cost. Similar symptomps to the previous video.

COMBINED 2: Combined skateboarding with pushing and steering. Changing goal positions are reached succesfully.

COMBINED 1: Too aggressive pushing leads to high velocity, leading to missing the last goals.

SINUSOID OLLIE 1: The system did a somewhat clean Nollie, where it pushed the board down with its front foot instead. This was also one rare attempt from many failed ones.

SINUSOID OLLIE 2: A 180 Ollie. One of the successful attempts.

SINUSOID OLLIE 3: Sinusoid Ollie attempt. The board starts rotating along the x-axis, causing it to land upside down, after which balance is lost.

SINUSOID OLLIE 4: Sinusoid Ollie. The usual outcome of the Ollie attemps, where the pose deviates and the board gets launched uncontrollably.

EMERGENT OLLIE 3: Emerging Ollie. This was one of the successful runs. Note the presented behavior was one-off, not easily reproducable.  The hands are not tracked or regularized in this run, resulting in uncontrolled flailing.

EMERGENT OLLIE 4: Emerging Ollie attempt. The planner is trying to maintain both balance and keep the velocity up.

OBSTACLE 3: Initializing a run down a hill into a small ramp and down a low box. The board gets disoriented, but the humanoid keeps track and recovers and starts to push in the new direction.

OBSTACLE 2: Initializing a run down a hill to easy stairs. The system humanoid keeps balanced, after which it switches to pushing.