Advice and opinions on hydraulic drive buggy

[chadsheppeard]

Hello Everyone,
I am interested in getting some feedback and opinions on a project I have designing a 4 wheel drive buggy. The application is pretty specific and i would like it to meet the following:
- max speed 30-40kms/hr
- weight 800kgs
- mainly operates at 0-15kms/hr
- only runs 5mins max at a time and about 1hour per day
- 50hp ICE engine.
My main goal is to design something that removes gearboxes, clutches, driveshafts, brakes that existing atv, side by side buggies have, as it is in very corrisive environment and when operating is under load all the time (on sand and no coasting) and these do not stand up to application.
I have considered electric but like the idea if hydraulic, I realize all the efficiencies, high speed
issues with this.
At the moment i am thinking either two (one each axel) or four motors (one each wheel) and would like opinions on following obstacles:
1. parrallel or series or switchable for two speed
2. best way to differentiate motor speeds for turning, spinning wheel
3. braking options using motors
4. starting or low rev torque of specific motors types
5. also considering running HP accumulator to compensate fir load flucuations.
I can work out gearing, motor sizing, pressures etc.
Thanks for your time and interest and appreciate any feedback or opinions.

 

[etudiant]

You did not mention a budget, but presumably money is tight.
Hydraulic motors are pretty common in agriculture and readily available, so you are on a good track.
The motor does not sound excessive for your requirements, hope that the rating is realistic, else you may want to scale down your speed expectations. The pump required may be your largest cost item.
You mention the device is to operate 'under load'. What does that mean exactly? Is 800kg the payload?
The project sounds reasonably involved when factoring in the control requirements. Have you considered starting with an existing chassis and just modifying the appropriate components?

 

[chadsheppeard]

Thanks for your reply.

Money is not the most critical factor, as i have priced components and looking at building 10 buggies at a time if prototype works - aiming at $20k each.
I am a diesel mechanic snd also run a fabrication and machine shop so have no issues with construction. I guess i am chasing confirmation or not if it would work or to get ideas what the best design would be.
I am flexible on engine size - just worked out approx hp needed.
when i say under load - the vehicle is driving in soft sand, sometimes towing so when moving is not ever off throttle or coasting.
I am thinking of grtting wrecked suzuki 4wd to use as a testing bef.