HELP NEEDED - E-WINCH for SPORTS

Joined
Jun 13, 2021
Messages
3
Hi everyone,

I'm new here so apologies if I'm doing this wrong!
Your thoughts and opinions on any aspect would be greatly appreciated.

I'm looking to build an electric winch for sports such as wakeboarding, skiing, snowboarding etc.

The motor doesn't need to be very fast but I would like to be able to vary its top / constant speed from say 20kph to 60kph.
The motor will however will need to be strong enough to pull a rider out of deepish water as it will predominantly be used for wakeboarding.

I would like to use the hub motor as the cable drum so I was thinking a scooter or moped style hub motor that has a wider rim would be easier to modify.
I would like a way of soft starting to build up tension in the cable, a short burst of high torque to pull out of the water then back of slightly to coast along.

Also, as the cable/rope is pulled inwards the diameter of the drum will increase slightly also increasing the speed. Is there a way to counteract this effect so the winch pulls at a steady programmable speed.

Thanks in advance and sorry if I have missed anything out.

Fred
 
Hi everyone,

I'm new here so apologies if I'm doing this wrong!
Your thoughts and opinions on any aspect would be greatly appreciated.

I'm looking to build an electric winch for sports such as wakeboarding, skiing, snowboarding etc.

The motor doesn't need to be very fast but I would like to be able to vary its top / constant speed from say 20kph to 60kph.
The motor will however will need to be strong enough to pull a rider out of deepish water as it will predominantly be used for wakeboarding.

I would like to use the hub motor as the cable drum so I was thinking a scooter or moped style hub motor that has a wider rim would be easier to modify.
I would like a way of soft starting to build up tension in the cable, a short burst of high torque to pull out of the water then back of slightly to coast along.

Also, as the cable/rope is pulled inwards the diameter of the drum will increase slightly also increasing the speed. Is there a way to counteract this effect so the winch pulls at a steady programmable speed.

Thanks in advance and sorry if I have missed anything out.

Fred
 
Hi everyone,

I'm new here so apologies if I'm doing this wrong!
Your thoughts and opinions on any aspect would be greatly appreciated.

I'm looking to build an electric winch for sports such as wakeboarding, skiing, snowboarding etc.

The motor doesn't need to be very fast but I would like to be able to vary its top / constant speed from say 20kph to 60kph.
The motor will however will need to be strong enough to pull a rider out of deepish water as it will predominantly be used for wakeboarding.

I would like to use the hub motor as the cable drum so I was thinking a scooter or moped style hub motor that has a wider rim would be easier to modify.
I would like a way of soft starting to build up tension in the cable, a short burst of high torque to pull out of the water then back of slightly to coast along.

Also, as the cable/rope is pulled inwards the diameter of the drum will increase slightly also increasing the speed. Is there a way to counteract this effect so the winch pulls at a steady programmable speed.

Thanks in advance and sorry if I have missed anything out.

Fred
 
SphericalNoob said:
The motor doesn't need to be very fast but I would like to be able to vary its top / constant speed from say 20kph to 60kph.
The motor will however will need to be strong enough to pull a rider out of deepish water as it will predominantly be used for wakeboarding.

I would use the Grin simulator to get an idea about whether your idea is feasible or not.

is this your desired towing speed? If so, you need an very fast wind motor and high voltage. Here's a MXUS 4503, which is fairly wide, with a fast wind. Assuming your cable wrapping around the motor/pulley is 9" diameter, you'll barely hit 60kph, and this is without simulating your load (simulator assumes flat ground and no wind, but includes wind resistance in the rider position (for ebikes) parameter. For your water resistance, you may be able change the grade parameter to simulate increased load, as well as the vehicle weight, which both impact the assumed load.

https://ebikes.ca/tools/simulator.html?motor=MX4503_SA&batt=cust_120_0.05_24&cont=C40&hp=0&axis=kph&frame=mountain&autothrot=false&throt=100&grade=0&wheel=9i&mass=100

You would need to estimate the water resistance, which would seem to be pretty high initially when pulling the person when they are initially submerged. Once you calculate that, you could use the simulator to change the vehicle weight and assumed grade, to increase the load used to match your estimate. However, the grade parameter maxes at 20%, so depends on how much load towing someone out of the water from a stop takes.

https://ebikes.ca/tools/simulator.html?motor=MX4503_SA&batt=cust_120_0.05_24&cont=C40&hp=0&axis=kph&frame=mountain&autothrot=false&throt=100&grade=0&wheel=9i&mass=100&cont_b=C40&motor_b=MX4503_SA&batt_b=cust_120_0.05_24&wheel_b=9i&hp_b=0&bopen=true&grade_b=20&mass_b=170
 
Big engine starter motor maybe?
 
SphericalNoob said:
I would like to use the hub motor as the cable drum so I was thinking a scooter or moped style hub motor that has a wider rim would be easier to modify.

Also, as the cable/rope is pulled inwards the diameter of the drum will increase slightly also increasing the speed. Is there a way to counteract this effect so the winch pulls at a steady programmable speed.
Hub motors are narrow to mount a tire, which will exacerbate the effective drum diameter change.

I'd highly recommend to separate the motor from a wider drum, which would also decouple motor speed from drum speed and allow you to independently vary drum speed via gear reduction.
 
Pulling things through water at a fun for doing tricks speed takes quite a bit of power (10s of HP). I bet your best bang for the buck would be finding a crashed Zero motorcycle with a working power-train to convert into a snorty winch.
 
I'm thinking you'd be better off making a circular loop, since you'd need a very long cable and it would be quite tedious unwinding it with a single drum winch.

I'm also guessing it's for a fixed installation... I've seen these made by the same people who make ski lifts (can't remember the company) and they used large industrial style induction motors, guessing about 20kW from the size.

You might be better off dealing with mains voltage industrial drives, which aren't all that expensive... 10kW of ABB drive is of the order of 2kusd I recall.

If you've got some odd portable application you think makes sense and want to run it off batteries, then the zero motor would definitely suffice and a moderate qs hub motor would probably manage for the kind of on-off time you're looking at with a single drum.
 
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