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Hydraulic Actuated Rear Wing system

AutoStudent25

Student
Mar 13, 2025
1
Hi, I am currently working on a project at Uni that involves coming up with an ECS for an adaptive rear wing system. I plan on using hydraulics due to their fast response time, I want to set up a pump attached to two accumulators which in turn are each connected to a solenoid valve and the linear hydraulic actuator at the start of one accumulator will be empty and the actuators top chamber full when the wing is required to tilt the full accumulator will empty into the bottom chamber forcing the fluid in the upper chamber back into the empty accumulator beginning a cycle in which the fluid is forced into accumulators from the actuator conserving energy. excess fluid from filling the actuator is rerouted with the solenoid valve to the pump where it is routed using a solenoid valve to whichever accumulator will be filled next cycle. WHydraulicSys.png
Will This concept work and what are things I should tweak?
 
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I don't understand your explanation. Flow-direction arrows and schematics indicating what is happening when, would help.

BUT. Three directional valves and two accumulators to control one cylinder? I understand it needs "forward", "stop", and "retract". If you have a single source of pressure (whether fitted with an accumulator or otherwise), a single directional valve, dual solenoid spring-centered with a closed-center spool, is all that is needed. Pressure to the center port, A and B to the ends of the cylinder, return-to-tank from the end ports (and the reservoir is the atmospheric-pressure reservoir for the pump). The pump needs to deal with being deadheaded appropriately. This layout is "fixed pressure variable displacement". This is a very common general-purpose hydraulic circuit design. Your average plain old ordinary industrial machine with a hydraulic power unit and a bank of directional valves to move various hydraulic functions, works like this.

Saving energy in that type of hydraulic circuit design generally means using a variable-displacement pump, so that you can turn it down to zero displacement when there is no demand. It still needs to maintain regulated pressure to achieve the maximum force on the actuator. This is not an inexpensive fixed-displacement gear pump. It's a variable-displacement vane or swash-plate pump. $$$, although lots of automotive engine oil and transmission oil pumps are variable-displacement vane pumps nowadays.

The other choice of hydraulic circuit design is something akin to old skool power steering systems, with a fixed-displacement engine driven pump (cheap, simple) delivering constant circulation through an open-center spool valve. Your input at the steering wheel shifts the valve which causes the pressure to build up in one side or the other, sufficient to overcome the load of the steering gear. "Fixed displacement and variable pressure". Doesn't work with an accumulator. If you insist on having a circuit design with momentary hydraulic flow into the cylinder that exceeds the instantaneous flow rate of the pump (thus needing an accumulator to store the pressure) then you're stuck with a fixed-pressure circuit design (with the pressure setpoint being whatever the storage pressure in your accumulator is).

If energy-conservation is a consideration, then hydraulics are not a good choice. Similar applications nowadays use a little stepper or servo motor to a gearbox to what amounts to a screw jack. No hydraulics. No standby power loss. Same reason power-steering systems have almost all gone to electric-servo nowadays.
 
Overly complicated and HEAVY.

Electrically driven ball screw or servo and bell crank will do the job better in every way.
 

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