Lego Mindstorms Nxt Humanoid Robot Instructions -

A humanoid robot must constantly perform a "controlled fall." The NXT humanoid has only two points of contact with the ground. To avoid falling:

You must calibrate the "Wait" blocks. If Wait is too long, the robot falls before the foot lands. If too short, the foot crashes loudly and the brick shuts off due to a stall error. lego mindstorms nxt humanoid robot instructions

Add a Light Sensor pointing at the floor. If the reflected light value drops (indicating a hole or edge), the robot executes an emergency "Back-up-and-Turn" routine. This prevents walking off tables. A humanoid robot must constantly perform a "controlled fall

Remember these final rules:

| Symptom | Likely Cause | The Fix | | :--- | :--- | :--- | | | Battery voltage low | Use brand new Alkaline or fully charged Lithium (NXT has a 7.4v minimum). | | Robot leans forward and falls | Center of mass too high | Move the NXT brick to the waist. Remove the heavy sound sensor. | | Motors click, no movement | Gear backlash in the knee | Replace #8 axles with #6 axles. Ensure cross-blocks are pressed fully flush. | | Turns one way only | Gyroscopic sensor drift (if used) | Reset the gyro by unplugging and plugging it back in while the brick is level. | | Ultrasonic sensor sees ghost obstacles | Cross-talk from second NXT | Switch to "Continuous" measurement mode instead of "Single shot." | If too short, the foot crashes loudly and