Hydrostatic ATV

[buickanddeere]

Wish I had taken a picture of a fellows mobility device I seen at our Fall fair. It took me a while to realize he was in a wheel chair instead of riding a ATV. It was home built it but coped with the rain soaked soil without hardly leaving a track. Wasn't very large either.

 

[kdlklm]

That would've been very interesting to see. That's the holy Grail of transportation for a person in a wheelchair, when they don't have to get out of their chair, and the machine is nice and compact. And just works well.

 

[PapaPerk]

That would've been very interesting to see. That's the holy Grail of transportation for a person in a wheelchair, when they don't have to get out of their chair, and the machine is nice and compact. And just works well.

What do you think the demand is for such a machine? How many people would be interested in one? I'm very curious. I think it's wonderful that a device can give people more freedom to roam and explore nature.

 

[kdlklm]

I am not sure what the demand will be, but for now I will be happy building one for myself. I am a wheelchair user myself. The costs are going to be high, probably around 15k to 20k. So I don't know what kind of price that would be on it.

 

[Kenneth S]

Just finished reading all 15 pages of this thread, I think you may find this intresting, The Ripchair https://www.youtube.com/watch?v=Qnrcr-rOcuw

 

[kdlklm]

I have seen that machine, but I didn't realize they had a new version. It look a lot better. Any idea what it goes for.

 

[Kenneth S]

Don't know what they cost since you can add different features, and what not, but it should provide some ideas. You can get a price quote here ULTIMATE  off road CHAIR FOR SALE - RIPCHAIR RC2 EXTREME OFF ROAD CHAIR

 

[kdlklm]

The project is not dead, I've been slowly working away at it. I'm at the point now where I need to start putting together the hydraulic components. Which is been proven to be quite a challenge locally, it seems that all the hydraulic companies in my area are busy with the oil companies and don't have time for projects like this.

We ended up using a four-wheel direct drive hydraulic system using hydro-gear HGM-8P-7181 motors. They are typically used on zero turn lawnmowers. The machine will weigh approximately 2000 pounds and I've had so-called hydraulics experts tell me that these motors won't even move the machine. With no matter what kind or size of pump I use.

I'm just looking for a little input and what other people's thoughts would be about the performance of this machine. You can view the latest photos at ATV Gallery

 

[buickanddeere]

Motor HP is chosen after knowing the volume and pressure of the hydraulic pump. The hydraulic pump size is known after calculation the wheel motor volume and pressure. Which requires knowing the wheel torque and rpm.

 

[farm boy00]

15-20k is your build price?? Why not for that motify a skid steer

 

[countrybrianf]

What is the torque specs on the motors you are using? I'm researching on making a hydraulic mud utv to be more dependable. I'm tired of breaking axles. haha

 

[4570Man]

Motors designed for a toy lawn mower might not work, but a real ZTR is 1200 pounds plus. A ZTR will run 12-20 MPH. I'm guessing you don't need to go that fast and could gear it down for greater toque. A skid steer would be a good place to start. I had an old skid that was sold for scrap, but first I pulled the all the hydraulics, and the motor out of it. The SS I tore down only had one motor per side and used chains to drive both wheels at the same rate. I could get a couple pictures of the SS drive train if you would like.

 

[Renze]

What is the torque specs on the motors you are using? I'm researching on making a hydraulic mud utv to be more dependable. I'm tired of breaking axles. haha

Generally, hydraulic motors have trouble generating torque from standstill because they have dead points. Like trying to take off on a bicycle with the pedal crank fully vertical: You can stand on it, but drop on your side before taking off.

Danfoss OMS motors (and their Eaton, Brevini, M&S equivalents) are orbit motors that have great startup torque for their displacement volume, and tapered roller bearings incorporated. the OMSW version is built extra compact, with its mounting flange put further to the center of the motor to move the bearings to the center of the wheel without the tire hitting the frame.

https://www.hydra.dk/store/hydra/en/product/2273687

 

[bigdeano]

Don't see that anyone has mentioned it, but you can buy two speed hyd motors if you want two speed ranges.

 

[Renze]

Don't see that anyone has mentioned it, but you can buy two speed hyd motors if you want two speed ranges.

variable displacement pump would be a better solution for a reasonably high speed vehicle like an ATV

 

[countrybrianf]

Found a website about this project. Has specs on the hydraulic motors. I think they will have plenty of power to do what you want. I'm looking to spin 34.5" Outlaw mud tires.

ATV

 

[countrybrianf]

Just found this. almost the same design as you have. You can roll into it on your wheel chair.

Track Chair Ripchair 3.0 The Ultimate Tracked Chair For Sale - Track Chair Ripchair 3.0 Extreme Off Road Chair