Hello,

Could someone give me a hint as to which robot is capable of completing this challenge?
I'm not finding one with the ability to lift the pen.
The bots I have available are:
LEGO REMBot, REMBot (w. Touch), Buggy Bot and Mammal Bot.

Thank you

Hello,
I came here looking for the same information. I ran across the layout diagram in the software and thought it sounded simple. I am just beginning to teach the subject and need all of the help out there. Glad I am not alone.

Hi DigitalMDX and nwatethis,
Holding pen requires a robot with a gripper. The only such robot in NXT mode is LEGO REMBot. This will allow you to draw continuous shapes, but as you point out there's no motor to raise and lower the gripper. This is because the NXT has a limitation to 3 motors, which are used up by the left wheel, right wheel, and open/close gripper. It is possible that we could have another NXT model that exchanged the open/close motor for an up/down motor, but we opted to focus on other features for this release.

The NXT license for Robot Virtual Worlds also includes access to the TETRIX platform (select LEGO NXT + TETRIX/MATRIX from the Robot>>Platform Type menu in ROBOTC). If you switch to TETRIX, the TETRIX Mantis robot has a gripper that can be raised and lowered.

Best,
--Ryan

The Lego Rembot will perform this task. Closing the gripper all the way makes the pen write, opening the gripper all the way stops the pen from writing.