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Don't disengage your controller. The purpose of a controller is not only to steer your system to the desired setpoint according to a predetermined dynamical response but also to counteract potential external factors that may impede this task. Think of a disturbance that will drive the system far from the setpoint once it has been reached. Thus, the ...


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Look in CommandCallback, where you set "stop = True". That sets a local variable, not the global variable you intended. Declare the variable to be global by preceding the assignment with the declaration "global stop". This contrasts with reading a global variable, which just works without declaring it (notably, in PathScanning). It might ...


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With consideration cheap, strong enough, not ugly and easy to shape, then my recommendation is you can use clipboard. I have seen people win international robotic competition with robot made using clipboard. So this idea worth to try. Figure 1. Clipboard


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There can be a few explanations for this: Does your motor controller (ESC) have an on-off switch? If so, try flipping that Some ESCs need to "arm". Try going to full throttle and back and see if that makes a difference I'm assuming you have your battery plugged in ;-) Try reversing the direction in the myconfig.py file


1

These battery charging messages are normal when the battery is charging. What happens when you take the robot off the charger? Have you tried putting the robot into safe mode (b'\x80\x83') before sending commands? Have you tried either of the scripts on the iRobot STEM github repo? Please note that I'm an iRobot employee but the postings on this site are my ...


1

It would be much better to determine a fixed sample rate for your controller. A really rough rule of thumb is that whatever the settling time you need out of the loop once it is operating in the linear regime, your sampling interval should be between 10 times and 100 times less than the settling time. Put another way, the sample rate should be 10 to 100 ...


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The Argon One case has a USB 3.0 M.2 adapter for the raspberry pi 4. So, you could use an SSD instead of an SD card, if that is where you're having issues. https://www.argon40.com/argon-one-m-2-case-for-raspberry-pi-4.html


1

The Lithium polymer and Lithium ion batteries are a staple for this sort of robotics rig. They produce voltage levels in multiples of 3.7-4.2v. You’ll need at least a 2-cell series (2S). Since your control circuitry will require logic-level voltages, you’d use a Buck converter to take the battery output down to 5v for the Pi and Arduino. 1A and 3A modules ...


1

For arduino and raspberry, powerbank is enough to power them for several hours. But the only problem i ever face when using powerbank is they sometime auto turn off because how little arduino current draw. For dc motor, use lipo or any equvalent battery. So you would have enough power to move your wheels and make your robot have better mobility.


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0.5mm 1x2m^2 sheet metal @ your local hardware store ~ 2EUR metal cutting pliers ~ 4EUR being able to cut it, fold it, punch* it for ventilation - priceless * use a nail and hammer/stone; rest on a disposable plank; punch from out to in; protect any PCBs, motors and especially wires inside from the jagged edges or neutralise those with a file or sillicone


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Cardboard on top of a cheap robot chassis can be quite effective. See this version of Openbot that does not use a 3d printer: https://custom-build-robots.com/raspberry-pi-robot-cars/openbot-your-smartphone-controls-a-robot-car-introduction/13860?lang=en I will typically use hobby-board plywood as a base and cardboard as a second layer. Get the hobby-board ...


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If you want to build a robot with lots of moving parts, or just a dedicated, aluminum building medium, and dont have a tight budget, you can use Actobotics building parts, from servo city.com (https://www.servocity.com/actobotics/) They are metal pieces with holes, so you can attach screws, other Actobotics pieces, servos, motors, and they even have mounts ...


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Consider things like food storage containers, dishpans, and household storage bins. Some (HDPE?) ones are reasonably stiff yet compliant, and you can readily cut them. Beware the beautiful, crystal-clear ones that are hard and brittle. If you're in the US, take a walk through your local Target or Walmart, and see whether some Rubbermaid or Tupperware shapes ...


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