If I have a Li-Po battery connected to four quadricopter motors...

[SimonLong13]

"Just having it hover" is kinda the hard part.

Sure, many can do it, but it involves feedback from various sensors that are each pretty complex.

If you just set all the motors to run at the right speed to get it to hover in some environment didn't mean you can give in another. Change the temperature, add a bit of wind, do it at a higher altitude, change a propeller, move the battery slightly, etc., etc. and it will no longer hover.

Making it hover in ground effect is much easier though. If flying only a few cm above the ground is OK, then your job is much easier.

That's exactly what I mean. Just a few inches off the ground

 

[SimonLong13]

That's exactly what I mean. Just a few inches off the ground

Not inches, centimetres.

 

[Audioguru]

What does your hovercraft do when you power its motors with the battery? Does it "hover"?

 

[SimonLong13]

What does your hovercraft do when you power its motors with the battery? Does it "hover"?

Basically, this is a question phase. I am still waiting for delivery of the parts.

 

[Gryd3]

Basically, this is a question phase. I am still waiting for delivery of the parts.

If you are just after a 'hover' affect close to the ground, you can ignore all the fancy controllers and rely on the 'ground affect' previously mentioned.
You will still need some kind of motor speed controller which you can do with some basic parts depending on your motor selection.
If you chose DC brushed motors, you can build a PWM controller with a 555 timer and some miscellaneous components. A FET or transistor to handle the motor's current, and a potentiometer to adjust the speed of the motor. You will be relying on the air from the propeller hitting the ground to lift your craft... you won't get much hight unless you turn up your motors, but if they are turned up too high it will simply fly off. Hovering without the ground affect would require additional controls or smart physical design to keep the craft upright, and some kind of feedback to maintain height.

 

[SimonLong13]

If you are just after a 'hover' affect close to the ground, you can ignore all the fancy controllers and rely on the 'ground affect' previously mentioned.
You will still need some kind of motor speed controller which you can do with some basic parts depending on your motor selection.
If you chose DC brushed motors, you can build a PWM controller with a 555 timer and some miscellaneous components. A FET or transistor to handle the motor's current, and a potentiometer to adjust the speed of the motor. You will be relying on the air from the propeller hitting the ground to lift your craft... you won't get much hight unless you turn up your motors, but if they are turned up too high it will simply fly off. Hovering without the ground affect would require additional controls or smart physical design to keep the craft upright, and some kind of feedback to maintain height.

Wow okay, so for a basic parts list, I'd need what? Sorry for the constant questions

 

[Gryd3]

Wow okay, so for a basic parts list, I'd need what? Sorry for the constant questions

If you are after a hovercraft, I would suggest brushed DC motors. (two wires... + and -) Buy them in pairs and operate half of the motors in the opposite direction as the others so the craft won't spin.
How far you want to build from scratch is up to you... if you want to go right down to the components, I would suggest getting a 555 timer and look at some example circuits to turn it into a PWM controller. You can then turn a potentiometer up or down to adjust the speed of the motors.
Run the motors in parallel, and hopefully build it so most of the mass is below the fans to help keep it upright. You may also experiment with ducting on the fans to help direct the airflow directly downward. (This also helps to increase airflow)

So... parts for a hovering craft. Simple, no feed-back, will require some fine-tuning to get a good stable height.

- Brushed DC Motors (In pairs). At least one pair. Paired Clockwise, and Counterclockwise motion required.
- Propellers. One for each motor, of course, Clockwise and Counterclockwise pairs to match the motors.
- Power source. Most likely battery. Lithium types for Remote Control planes/cars are lighter and can deliver more power than AA batteries. The choice is yours depending on flight time, and how much lift your fans make.
- On/Off switch.
- PWM Controller. (One should be fine if all motors are connected in parallel.
- Misc. parts to build the body.

That's where I would start, but be warned this will only hover if you put the time to experiment into it... I can't give you part numbers to buy that will make a hovering craft.

 

[SimonLong13]

If you are after a hovercraft, I would suggest brushed DC motors. (two wires... + and -) Buy them in pairs and operate half of the motors in the opposite direction as the others so the craft won't spin.
How far you want to build from scratch is up to you... if you want to go right down to the components, I would suggest getting a 555 timer and look at some example circuits to turn it into a PWM controller. You can then turn a potentiometer up or down to adjust the speed of the motors.
Run the motors in parallel, and hopefully build it so most of the mass is below the fans to help keep it upright. You may also experiment with ducting on the fans to help direct the airflow directly downward. (This also helps to increase airflow)

So... parts for a hovering craft. Simple, no feed-back, will require some fine-tuning to get a good stable height.

- Brushed DC Motors (In pairs). At least one pair. Paired Clockwise, and Counterclockwise motion required.
- Propellers. One for each motor, of course, Clockwise and Counterclockwise pairs to match the motors.
- Power source. Most likely battery. Lithium types for Remote Control planes/cars are lighter and can deliver more power than AA batteries. The choice is yours depending on flight time, and how much lift your fans make.
- On/Off switch.
- PWM Controller. (One should be fine if all motors are connected in parallel.
- Misc. parts to build the body.

That's where I would start, but be warned this will only hover if you put the time to experiment into it... I can't give you part numbers to buy that will make a hovering craft.

Thanks. This is really helpful. I've got most of that, need a switch though. I'll see if I can find I one small enough, and I have a good enough frame to position it symmetrically.