Walking: tune walk kicks

[jaagut]

Is your feature request related to a problem? Please describe.

We cannot kick at the moment.

Describe the solution you'd like

We should use the walk-kick feature instead. Don't do this by moving the foot further and back again after touching the ball, but rather setting the foot down after accelerated step-movement. Side-kicks are also possible by rotating the foot. Afterward, we may need to revert the foot rotation. Look at Hulks or other SPL teams for details.

Describe alternatives you've considered

[00lake00]

2 components: walking (parameter tuning) + behavior (call walk kicks)

implement action in bitbots_body_behavior > actions

replace some dribbling actions with the new walk_kick action --> evaluate when

[00lake00]

Observations while working with Amy

• 2/3 of the cases she does not fall over when executing the walk_kick
• Shooting range only about 20-30cm
• Repositioning the foot after kicking makes her sway the most (back motion too fast)
  • May be the biggest problem in making her fall
  • (1) Is the foot getting positioned in the same position as before after that or in the position of a step?
    • could solve the balance problem if set a little bit further
• Three variables to adjust: length, phase and velocity
  • (2) What does velocity? Still needs to be iterated on in the simulator in slow motion

[Flova]

I would guess that length determines how far the foot moves to the front. Velocity determines how fast the foot should be moved and phase determines at which point of the walk cycle.

[jaagut]

Yes, we tested those parameters. The length is the most obvious and does, what you described.

The phase parameter seems to define the time-fraction relative to the walking phase the kick should take. Default was 0.75. With 1.00 the whole kick took longer, with 0.5 the kick finished quicker.

We did not notice any change when adjusting the velocity parameter. Perhaps we didn't test enough values, or it does nothing. Needs to be investigated.

However, at some point, we noticed that the second movement (moving the foot back) is way faster than moving it forward. Changing the parameters did not seem to influence this. Such a jerky movement should not occur, as it may lead to falling.

[00lake00]

Meeting with Flo and Jan

• lower frequency of step and phase reset would be helpful in keeping balance @Flova
• kick_phase parameter should be 0.4/0.5
• velocity nice for longer kick
• roll for longer kick?
• longer foot down length for kick than normal walking? --> balance issue for big step after kick but with small difference nice

TODO

• parameter tuning on real roboter
• plotyuggler show joint position error

[timonegk]

Walk kick should be adapted to the current kick animation