I want to use a thumb throttle (like the one from an electric scooter) to run motor back and forth. I have the jrk 12v12 and when I setup the throttle and have the program “learn” the settings it always wants to keep the middle as neutral. I want to push the throttle all the way down and have it run the motor forward, then on releasing the throttle have the motor run back to it’s original start position…Is this a possible configuration with the program and if so how? Thanks for the help.
In general, you can have the different positions of your throttle scaled into a range of target values that you select. However, you are asking for a combination of no-feedback control (“run the motor forward”) and feedback control (“run back to it’s original start position”), which might not be something you can do with the jrk, depending on your specific setup. What kind of feedback sensor are you using that you expect will be able to tell you when you get to the “original start position”?
I am planning on running a linear actuator basically so the jrk should run it “out” and then “in”. The feedback sensor will likely be a string pot or a scale pot of sorts (like those on a sound board).
You can configure your jrk to use a potentiometer as a feedback source, and your input device can be mapped to the range of feedback values in various ways. If you need a more specific answer, can you describe what you want more clearly?
The linear actuator will be pushing a lever approximately 6 inches where it will then hit a stop point. I would then like it to reverse direction and return the lever to its original starting position. However, in doing this i would like the input to be a thumb throttle pot where its direction of travel runs in proportion to the direction of travel of the lever.
What you can do with the jrk is link your throttle position to the lever position, so that when you push it down, the lever moves forward, and when you release it, it goes back to the neutral position (which can be set to whatever position you want). Is that good enough for you? It is hard to tell exactly what you want, because it is not clear when you say “I would then like it to …” whether you are talking about something that it will do in response to an input, something that it should automatically do as the next step in a programmed sequence, or something else entirely.
I suggest that you start by following the step-by-step instructions in Section 5 to set up the basic feedback system, before you worry about how your input will work. Then, once you are able to control your system as well as you need to with the slider on the input tab, try configuring your input settings to do what you want. In general, if you want some kind of programmed sequence of multiple motions to happen in response to an single input, you will need to write a program on a separate computer or microcontroller.
well, partially yes…I do want the throttle linked to the lever position. So pushing the throttle forward will make the lever go forward, however releasing the throttle will need to essentially make the motor run in reverse. The motor pushing the lever is a linear actuator so extending the actuator and retracting the actuator involves reversing the polarity of the inputs, therefore, releasing the throttle to neutral would merely keep the actuator static and not create the reversing of polarity to retract it wouldn’t it?
It is really important for you to learn the difference between the jrk’s analog feedback and no feedback modes:
In analog feedback mode, the motor will run forward and backward as necessary to reach the target, which is controlled by the input device.
In no feedback mode, the input device directly controls the PWM speed of the motor.
I think you want to be using the analog feedback mode for this project.