Award
Congratulations Richard R, for answering the question and has received an EZ-Credit award! Share what you have learned and create a tutorial to help others by clicking here.

Linear Vs Exponential Motion?

Assistance Requested

Help gwen4156 with their question and receive $10 of EZ-Credit to get more robots and parts from our store. The following information was provided about their previous efforts searching tutorials for a resolution.

gwen4156 claims to have checked these sources:
 
#1

I am controlling my B9 robot (i.e. The G-Bot) using a Sabertooth 2x25 with EZB v3. Is there a way to set the Sabertooth or EZB so my robot's motion is gradual (maybe exponential vs linear)? The G-Bot will have a rather high center of gravity when fully assembled and the way the lower half is buzzing around in my garage it would've been on its side by now. As it is I think I could have driven it right through the garage door.

I could put a blade on it and use it for plowing snow in a few weeks Smile

Thanks in advance!

I have found a few conversations, tutorials and activities that may help with your question. Take a look at these links. I've sorted them by what I believe to be most relevant but that is not always the case as I'm still learning.


Also, consider reviewing the Learn section for informative lessons and activities. Check it out!


#2

You can lower the speed of the motors by simply changing the numbers in the sabertooth control panel... No need to use full speed all the time... If you need more control like ramping you can use a custom Movement Panel and scripting to control the sabertooth instead... Using variables as well will make it easier to change the speed of the sabertooth on the fly.... With a little bit of scripting you can create a type of 'throttle" control for your robot....

#3

I believe one of the functions of the Kangaroo board (that attatches to the Sabertooth and takes encoder inputs for precise positioning) also supports ramping speed up and down. I don't have one yet to play with and was just going to use the method Richard describes to start with, but I am intrigued by the Kangaroo and encoders after reading about them here.

Alan

#4

Thanks guys.

#5

I finally got a joystick (game controller). It works well linked up to the Sabertooth H bridge control to control the G=Bots two drive motors but -due to the weight and high cg of the G-Bot - I'm going to need much precise and variable control.

Can anyone point to a tutorial that may give suggestions (script, other controls, or a combination) that will allow me to achieve this?

Also, the axis of the joystick control is 90 degrees off what I want. Is there an easy what to change that?

What about custom assigning other buttons for other functions? I've gotten the soil sampler to deploy with a joystick button using Rich's E switch and I've experimented with using some other simple script to try and achieve control of the torso rotation control motor using joystick 2 (using a diverse electronincs H bridge) but, again, I need much better control (variable speed and direction ramping, etc). When I tried to add another H bridge control to control the torso rotation with joystick two, EZ Builder won't allow more that ONE Movement Panel at a time? What's up with that?
E Switch

Is there anything like a primer on how this all works? (specifically: what is scripting? Is it a language? , how does serial motor control work?, advantages of using PWM vs serial with available premade controls?)

I know I have much to learn to get the G-Bot where I want him by Halloween and I'm not even really sure where to start.

Any help ans suggestion much appreciated as usual.

Thanks