Hello all,
Our team’s robot is having an issue with keeping its arm in the air after being lifted. Our idea is that once the arm is raised and the button controlling it, the gears in the arm will lock it in place and keep it in the air until it is manually raised or lowered. Attached are various photos of the robot in resting and raised position. Is there a method to keep the arm in the air without having to continuously tap the button?
Short answer: sensors, programming, and supporting the weight with rubber bands/surgical tubing.
For a sensor, some kind of potentiometer or encoder to measure the rotation of the joint to be stabilized.
For programming, you will need some kind of PID position-keeping algorithm.
To support the arm you have there with elastics if it is designed to reverse direction like I think it wants to would be tricky, but it should be doable.
Hopefully that gets you looking in the right directions.
Sure, you could do what @John TYler suggests electrically, or you do it mechanically. The suggested rubber bands would work well, or you could up the torque of the arm itself externally with compound gears. Of course, this would be at the expense of speed.
Also, servos have a suprisong amount of torque output. If you feared it at about 1:3 for torque, you should be pretty much fine.
But, the arguably “best” way would to do what @John TYler suggested and use your code to accomplish the task. But, if you’re not quite experienced enough to do this effectively, mechanical strengthening is always an option.
Does anyone have problems with the arm raising on the V5s? We are building the standard clawbot and for the life of me - that arm will not raise. It’s like it is too heavy and I have used rubber bands. Any suggestions? I’m pretty sure we followed the instructions.
Can you post pictures?
What is the gearing on the arm? I’ve now built seven V5 clawbots and lifting the arm with a 1:7 gear ratio is no problem at all, even using the 200RPM (green) gearboxes.
Thanks! I took it home last night, and it is there today disassembled. Can you post close up pics of your clawbot arm? Maybe even with the claw attached too? Is there maybe a how-to build video out there? We follow the steps, but some of it just falls apart.
