LEGO Engineering

| | | | | | | |
When I use the "stop" command in ROBOLAB 2.9, the motors only coast to a stop. How can I command the NXT motors to stop on a dime?


23rd of April, 2010

(1 )
100% thumbs up 0% thumbs down

In the initial version of ROBOLAB 2.9, the stop comand does not work properly. The NXT motors coast to a stop rather than stopping abruptly.

There is a way to program around this bug in Inventor so that the motors will stop abruptly without reversing direction:


1. Insert an "Optimize" function to set the motor to brake in between pulses. (You can also use Detective to set the motor pulse mode to brake.)

2. To stop a motor, instead of a stop command, insert a motor speed command and set the motor speed to zero.
3. If stopping a motor is your program's last command, insert a wait-for command of at least 200 msec immediately after setting the motor speed to zero. (You need to do this because the firmware commands the motors to float to a stop when the program ends.)

stop_motor_vi.jpg


Alternatively, there is an update for
ROBOLAB 2.9.2 that eliminates the problem with the stop command. With this patch, you can use the stop sign instead of setting the speed to zero. Patches for ROBOLAB Software are available here.
Before downloading this patch, make sure to check in "About ROBOLAB" that you already have version 2.9.2 or higher!
   :
   :
* :
* :
 


Home | About Us | Contact Us

© 2013 Center for Engineering Educational Outreach, Tufts University
© 2013 The LEGO Group. All rights reserved.