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41

For quadcopter designs, you generally want to have around a 2:1 thrust-to-weight ratio. That is, at 100% throttle, you want your combined propeller thrust to be capable of lifting two times the weight of the craft. You then need to determine the amount of power the motors need to generate that thrust (usually given on the datasheet). When you have that ...


11

If I were you, I would first (1) read the LM2576 datasheet. I'm assuming you are using a circuit similar to the schematic and PCB layout on page 23 of the LM2576 datasheet. I'm guessing you've tweaked the circuit slightly, replacing the manually-operated pot shown on the schematic for R2, replaced with some sort of microprocessor-controlled thing that ...


10

As Rocketmagnet mentioned, just because a motor is rated at 2.5 W doesn't mean it will be pulling 2.5 W all the time. Most robots have at most 1 or 2 servos that are running at full power at any one time; the rest have very low mechanical loads (and therefore pull much less electrical power) or are "off" and therefore pull practically zero electrical power. ...


8

It's always difficult speccing the power supply for a robot, and you've hit the exact problem we all face. Do you spec it to cope with the typical load, or the absolute maximum load when all motors are stalled at max current? There's no right answer to this, except that whatever happens it shouldn't damage anything. The good news is that the servos probably ...


7

You'll have to determine yourself whether a motor controller shield is compatible and can be stacked on your existing shield. In some cases, you can use Arduino's SPI. In other cases, you'll need to check whether the pins that your shield uses would conflict with the pins needed by a motor controller.


6

There are a variety of reasons to separate the motor power from the "hotel load", including: Reducing the number of wires running between high-power and low-power electronics Redundancy (your homing beacon shouldn't run out of power when the rest of the system does) Preventing heavy current loads from browning out the control system Making the system more ...


6

The batteries should weigh roughly the same as everything else on the airframe combined. With a given aircraft -- everything known except for the mass of the batteries -- the absolute maximum flight time occurs when the weight of the batteries is twice as much as the weight of everything else on the airframe combined. However, many other characteristics -- ...


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

According to the datasheet, there are three possibilities: TTL shutdown, thermal shutdown and current limiting. From what I looked up, TTL shutdown means simply that you have a pin you can use to cut-off the regulator output current. My guess is that it is pin 5 and you simply grounded it, as seen in the typical application circuit, so that possibility can ...


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

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

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

You can also add between the controller power an electrolytic capacitor of about 500 or even 1000 microfarads x 12 volts and a diode in series with it, so when the trigger pull much current source with a corresponding drop in voltage will be avoided that Power down controller please and even free you from unwanted noise (about 10 turns of cable around a ...


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

The short answer is no. The longer answer requires more information from you, regarding how the motor is to be used. Since you have tagged your question with "quadcopter", I'm going to assume that you plan to put the motor on a UAV, in which case more power definitely does not mean "better". More power (W) will draw more current (A) from the battery (...


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

Forgive me I seem to get caught up in people looking for answers to a question they didn't ask a few times already. So given this question; "How do I determine how many amps will be needed from the power supply?" You can roughly guess it, in your case you say 4 servos drawing an amp each, 4 amps total. Pick any BEC that will supply greater than 4 amps, ...


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