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Handling the Booster

This documentation describes how to handle the Booster T1 and K1 in different situations.

Note

The real K1 is currently only partially supported. The button interface is not done yet (do not press them!) and the camera support is not finished. Also the provided learned walk could only be tested once due to time constrains and is only suitable as a proof of concept. Similar stands for its PD motor parameters, which are only guessed by us and not evaluated yet.

Inactive

Whenever the robot is not used, it should be stored on its stance:

Stance

Turning On

The robot can be turned on with a short press on the power button. After booting up, it will say "waiting for robot body". If everything started correctly it will say "body ready". This process can take up to three minutes.

Button Interface

Our software assumes three buttons exists on the K1 as well as on the T1: WALK, STAND, F1. For the T1 those might be unlabeled, but we assume the same sequence as on the K1.

  • Stand: Switches the robot into a static stand posture as well as switches the internal playing states.
  • Static Stand: The robot moves into a standing pose with low stiffness and no balancing. This mode is for carrying the robot. Do not let the robot stand without holding it, as it will fall without human help.
  • Playing States: The stand button switches between the states Unstiff -> Initial -> Penalized <-> Playing
    • The robot will never move as long as it is in the static stand.
  • Walk: Turns on the normal motion for the robot. In this state the robot is allowed to walk, kick, get-up, and so on. In this state Do not lift up the robot. Learned policies are active and the robot might start harmful motions without ground contact.
  • F1: An second emergency button, which turns on the Damping-Mode of the robot. To leave this state and bring the Booster robot back into the custom mode, keep the button F1 pressed for 3 seconds.

Buttons

Note

Please validate for your T1 before use, if the button mapping works as expected, especially if you only have two buttons instead of three as shown in the image.

General Use

When turned on, the robot can switch between different states as shown in the following image with the button STAND (Source: RoboCup SPL Rules 2023):

States

  • You can switch from Unstiff to Initial to Penalize to Playing and back to Penalize with a press of the STAND button (gray arrows).
  • Standby, Ready, and Set can only be reached in some demos or via the GameController.
  • Calibration is described in the calibration chapter (purple arrow).

We recommend to keep the robot on its stand-structure when unstiff and pressing the STAND button for a standing pose. Be careful, as the robot does not balancing itself in this state. When the WALK button is pressed, the robot uses its neuronal network for walking, so lifting the robot up (even when standing!) is prohibited and dangerous.

To prevent damages to the robot itself a restrictive fall will be active once the robots torso is tilted too much. Here the robot uses a semi-damping mode to reach a standing position but also to prevent damages to the motors. As stand-up motions are currently not supported, we highly recommend to disable them for the real robot. Note that this behavior is inactive when STAND was pressed. If the robot falls in this state, no safety is active.

Handle Example

Shown below is an example how to handle the T1 for a test walk:

Safety Instruction

TODO

  • The height of the robot itself is the danger-zone. Human arms, hands and head are NOT allowed inside this area. A human itself standing upright is allowed.
  • The lower legs are very dangerous and human fingers can get inside those and get damaged or even get removed. No body part except the legs are allowed near this robot area.
  • The robot has a handle. It is only allowed to be grabbed with the hand facing upwards and grabbing it from below. Grabbing it with the hand facing downwards from above is forbidden, due to the risk of the hand getting stuck inside the robot head area.
  • Wearing shoes while working with the robot is a must. Not wearing shoes is forbidden.
  • The robot while walking and falling is no danger as long as human hands and heads are kept above the robots height. The robot colliding with a human leg or sole pose no more danger than interacting with a small human child.

Possible Problems

Here we list possible problems that can occur while the Booster robot is being used.

  • Emergency: The emergency button was pressed and the robot is unstiff. Press the F1 button, release the emergency button, keep the F1 pressed for 3 seconds to return the robot into a safe unstiff state.
  • Unstiff while playing: The robot itself has some safety features, which can trigger this fail-safe. One reason could be a joint overheating.
  • Sometimes the motion board is not reachable for the T1. In that case nothing happens and the robot must be turned off and on again.
  • Sometimes the audio does not work and the robot does not say anything anymore. In that case the robot must be turned off and on again.

Gamepad Control

Note

At the moment, gamepad control is only available on the K1.

Each Booster robot comes with a gamepad that is linked to that specific robot. All gamepads are labeled with the name of the robot they are connected to. The gamespads can be switched on and off by pressing the home button for a longer time. For the connection to work, the receiver mode slider on the bottom side of the gamepad must be shifted to the right (not Bluetooth). In addition, the lower three LEDs above the button M must be on. If they are not, the button M can be used to switch the mode until they are.

The gamepad control can only be activated when the robot is in walk mode and the joints are stiffened. Pressing the left trigger and ⊕ on the gamepad simultaneously activates remove control. It can be deactivated again by pressing the left trigger and ⊖ simultaneously. The gamepad control will automatically be deactivated when the buttons F1 or STAND on the robot are pressed as well as when the gamepad is switched off. The latter will also happen automatically if the gamepad is unused for 10 minutes.

Gamepad control scheme


Last update: January 17, 2026