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6

It is called a slip ring. It works the same as a brushed motor. See here for a robotic oriented one. Larger versions handle power, and cost more. Also near field technologies such as those used to wirelessly charge your electric toothbrush, and more recent wireless cell phone chargers, are potential solutions


5

There are a few ways to read your question, but in general what you are suggesting is a bad idea. The only reason to do it would be in the extreme case where splitting a large battery into several smaller batteries would help you find space for them in a tightly-packed chassis, and even then it might be more trouble than it's worth -- quadrupling the number ...


5

The battery capacity specification (eg X mAh) tells you that your battery can run for 1 hour providing X milliamps until it is depleted. This doesn't always scale with time, for example you probably won't run for 1/2 hour if you draw 2*X milliamps, but this is another discussion. To answer your question, a greater mAh will allow you to use your battery for ...


4

I agree with @Greenonline 's recommendation regarding LiPo batteries along with his warnings on battery care. It seems you will need a fairly small battery, considering your current requirements (about a 1000-2000mAh 2S LiPo). However, you also need to add 2 5V BECs (5V regulators in RC lingo) to power your circuits; The 7.4 or 11.1V provided by the battery ...


4

Industrial Robots with having as aim manipulation of large objects are powered electrically in almost all cases (30-40 years ago there have been popular hydraulic variants). Industrial robots are powered by industrial 400V 3 phase current, so in a sense, they are plugged in a wall outlet, but but a household wall outlet but an industrial one, like this. ...


4

Robots tend to be portable devices powered by batteries. Portable battery operated devices tend to use embedded processors with limited power and memory. Compiled code has several advantages over interpreted code in such applications: Compiled code usually takes up less space. So you can have more code in the same amount of space. Compiled code usually ...


3

You can control brushless motors 2 ways control with a hall effect sensor http://scholar.lib.vt.edu/theses/available/etd-09152003-171904/unrestricted/T.pdf sensorless(back emf) control http://www.pmdcorp.com/downloads/app_notes/BrushlessSensorConfig.pdf or you can buy an esc (elcetronic speed control) My advice If you are not knowledgeable about electronic ...


3

This is very rough, might or might not help you.... Treating it as a macroscopic perspective: Kinetic Energy $$E_k = \frac{1}{2}mv^2$$ For working energy in a flow, substitute volume with Area*Velocity and mass with density $\rho$ $$E_k = \frac{1}{2}\rho Av^3$$ With that, you should be able to estimate (after efficiency corrections) the power required....


3

Yes this is pretty easy to solve, you just need basic soldering skills. Just open the cables of your additional USB-devices, you will see 4 wires. 2 of them are for the data, just leave them. The other two are for powersupply, just connect them to your 5V power supply. But make sure you have to right ones, otherwise your device will start producing magic ...


3

A linear regulator has a major drawback: it dissipates the power it doesn't deliver. Using the well-known 7805, the output voltage is 5V, your input shall be at least 7V to allow a good regulation (2V dropout voltage), if your load requires 1A, your 7805 dissipates 1A * 2V = 2W. This makes your Linear regulator hot. The best efficiency you may expect from a ...


3

Your scenarios are correct. You can connect multiple solar cells together to get increased current or increased voltage. Wire them in series (positive to negative) to boost voltage, wire them in parallel (positives to positive) to boost current capacity. As a final note, I would caution running near the maximum capacity of the solar cell. The voltage of ...


3

Search aliexpress for '6V switching power supply'. You should find 5Amp or 10Amp ones for $10-$20. Silver boxes with holes in them. You can find them on ebay as well (usually the same chinese vendors as aliexpress). You will need to add your own AC plug. Keep in mind that you will probably not be using 12Amps because not all motors will be at full torque ...


3

What you're asking for cannot be accomplished with a PID controller. As I understand your question, you want to be able to choose PID gains that would always produce a "good" trajectory, without tuning. You said it's alright if the motor output is unrealistic, i.e. the motors are "very strong" therefore can produce unlimited torque. ...


3

You could trick the charger into providing power for you by applying a voltage to the balance sensing lines. However the control you have over it would be limited. Switching power supplies are ridiculously cheap these days. Search ebay for "switching power supply dc 24v" for whatever voltage you want. I just keep a pile of these in the closet for the ...


3

Sure, a drone can land on a powerline. That's a standard task like the "peg in hole problem" for robotarms. The aim is to maneuver a UAV near to a highvoltage line and eating all the energy. The earliest paper was written in 2009 and has a nice plotchart of the Electro-Magnetic Field on page 8 Powerline perching with a fixed-wing UAV for directing the UAV in ...


3

I think yes it can but how? My options are here: Static system for conventional systems It should stand or hang to line/pole/special place like birds. Please watch video for an example: https://www.youtube.com/watch?v=MvRTALJp8DM Dynamic system Harmless/secure distance present day wireless charging methods: use low energy harvesting drone or an ...


3

Every action has an equal and opposite reaction. Each motor/joint in a linear chain of actuators (snake) needs to be capable of supplying the appropriate reaction forces. This mean that, if you have a 100cm long snake robot with a motor every 10cm, the first/"neck" joint (at 10cm) needs to support 8 other motors and 90cm of snake body. The second joint ...


3

Power (Watts, milliWatts, etc.) is given by: $$ P = IV \\ $$ where $I$ is current in (milli)Amps, $V$ is voltage in Volts, and $P$ is power in (milli)Watts, respectively. Energy (Watt-hours, milliWatt-hours, etc.) is given by: $$ E = P\Delta t \\ $$ (assuming constant power output), where $E$ is energy in (milli)Watt-hours and $t$ is time in hours. ...


3

Looks like it uses a propane powered ram to launch itself into the air. The end of the piston is visible in the back of the vehicle. This webpage states that source of power is battery and propane https://bostondynamics.com/sandflea Also found this patent for a combustion powered linear actuator. https://patents.google.com/patent/US7263955B1/en


2

18 servos is a lot of power no matter their size but you are going to need to be more specific with what kind of servos you are talking about. That said, this What is the best way to power a large number (27) servos at 5 V? is a good answer to your question.


2

Use a self-powered hub. Look at the power adapter from the mains (220v). In almost all instances, it is converting 220vac to 5vdc (sometimes 5vdc and rarely 12vdv). Cut the power adapter cable to the hub in half after determining which half of the cable pair is negative and which is positive (see picture below). Often it's as obvious as the red wire is ...


2

As long as the steppers are running relatively slowly, let's say a few hundred steps per second, you should be fine. Your driver uses PWM to control the current through the motor windings. In microstepping mode the driving waveform at the motor terminals looks like a sine and cosine (sines offset by 90 degrees) and the driver modulates the outputs to ...


2

I use those RCtimer ESCs and they have always worked great for me, generally thease (and most) ESCs will be looking for 50Hz pwm with a period between 1-2ms, though generally you will not damage them by altering the pwm output. I would recommended cutting the 5v supply on each ESC as they can act funny and even damage themselves when they are all tied to ...


2

Well.. It was a power issue! I'm using one of the arduino replicas and the 5v pins is only outputting 4.5v instead of 5. The problem was solved by providing an external power source. I don't find it cool to power robots externally but this is the only way in my case.


2

The easiest way to calculate this will probably be by using the ecalc helicopter calculator, they have done all these calculations for you and take into account far more factors in my experience they are very accurate. I know that most props have a Prop Constant in the 1.1 to 1.3 range, but for your specific situation according to ecalc gives a thrust to ...


2

You are right that there are issues in having an "unclean" power supply running into your RaspberryPi. If you are drawing tons of power, things get very hairy very fast. However, there are ways to "convert" and "clean" a supply to isolate the voltage (and therefore making it suitable for input to the Raspberry Pi). How much cleaning will depend on your ...


2

The device you are looking for is broadly known as a slip ring, but since you are trying to power other motors through it you should be aware that a slip ring is not electrically identical to a wire. Depending on the amount of current you are trying to send, the slight variations in impedance that your slip ring will produce as it spins can damage some ...


2

The alternator in a car is constantly charging the 12V battery while the car is running, which is to say battery-wise you shouldn't have any issues. Several things could be meant when you say the motors are "rated" for 12V. Is that a maximum, minimum, or nominal voltage? I'm assuming they're rated for DC power, but there are some low voltage AC motors. ...


2

n = Kv * Vin only when there is no load on the motor. When there is a load on the motor, like from a propeller, you will need to be a bit more clever. For a DC motor (which BLDC motors approximate by varying the Vin): Torque = Kt * Vin / R - Ke * Kt * n / R (Derivation example here: https://electronics.stackexchange.com/questions/90933/torque-relationship-...


2

Regarding the battery requirements, LiPo batteries are probably the way to go, but they do require looking after in order to prevent any nasty accidents from occurring. I looked into this a few months back, you might want to take a quick look at Service, Please! and Power Up!. Isolating the power supplies, as you suggest, is probably also a good idea. ...


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