This may be best for wish list category but was wondering if there is a hardware or software solution for being able to move the arm once a program stops for whatever reason and the arm is too high to resume. We always bring the arm down and end of routine and always send it down at beginning, but we avoid keeping that arm down at beginning for more than a few seconds to avoid what I think it not good for the motor to be pressing down on the stop bar we have in place to prevent damage to processor. We have a block routine that does nothing but drop the arm that I can run instead of the primary routine especially when you’re in middle of a competition.
How to move Ultimate 2.0 Robot Arm when the Ultimate is turned off?
Hugh
#2
I meant to say that substituting for a routine that only lowers the arm is not ideal during a competition. Also in the past I have used a tilt switch to monitor for the arm being in the wrong position. I’m sure the Ultimate gryo could handle this but I haven’t gotten that far in using it.
Rosco
#3
I can’t really help you with that. It should be the belt, you may have to tighten that, but otherwise, I do not know.
Can you elaborate on what you are trying to do?
CommandeR
#5
Hi @Hugh
You don’t say which Ultimate (1 or 2) you are using - I’m guessing 2 although the ‘belt’ that @Rosco refers too is from the Ultimate 1 kit.
I did quite a lot of experiments with Ultimate 2 and wrote on page 28 of my 2020 book referring to it:
"Robots need fail-safe methods to keep themselves and us from harm and many methods can be employed to do this. Limit Switches are a vital component of robotics applications by preventing mechanisms from moving too far in one direction or another (or stopping if they have hit something!). These tend to be small (micro-switch) sensors that provide simple feedback (have they just been pressed or not) - i.e. has another component has made contacted with it? N.B. Makeblock do sell, as extra add-on components, their own versions of these (and some useful angle-measuring sensors too).
But could the three main sensors supplied be used effectively as alternatives to limit switches?
The Robotic Arm Tank has three different working movements:-
- The tank has multiple directions of movement but if controlled using keyboard press / release keys it will stop as soon as a key is released, so no limit switches are required here."
The next four pages are reproduced below:
I do hope that this helps.
Hugh
#6
In addition to all that CommadeR wrote which is great, I’m also interested in a hardware, mechanical solution that allows the Ultimate 2 arm to be moved when power is off.
Best_codes
#7
@Hugh Oh! I don’t think you could move the arm (with the Ultimate board) when the power was off. You could do it with another board, perhaps, but it would be a bit impractical. What are you trying to accomplish?
Hugh
#8
We have instructions to team to never move the arm by force. So what i am asking has anyone devised a way to disengage the arm motor in simple way to allow for repositioning of the arm
Rosco
#10
The robot has to be powered on for the arm to receive power. I don’t think that is possible unless you apply a voltage to the motor that lifts the hand, or apply a voltage to the hand directly, but because there is no code going to the controller that handles both of the motors for the arm, the arm will go down, because, again, there is no instruction from the controller. I don’t think it will even move when you apply voltage to the motor. But just try it if you want to risk the arm. Again, TRY AT YOUR OWN RISK.