Active Rear Wing Control System. Help Needed

It would be better to use a pair of microswitches rather than a potentiometer - they are easier to interface and much less affected by heat and dirt. You will need to find a convenient spot to mount the switches, probably on the actuator or nearby. You arrange the switches so that the actuator switches them on at each end of it's travel.

What might be even easier to set up is three switches that indicate the positions of the wing since the up & down positions of the wing are essentially the same as the actuator's limits. The middle switch indicates the neutral position and you just need to adjust the switch positions on the bracket to fine-tune the wing position.

The switches will be connected to three digital input pins on the MCU and the software will use the switch inputs to know when the actuator is in the right position.

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Originally Posted by overkill

It would be better to use a pair of microswitches rather than a potentiometer - they are easier to interface and much less affected by heat and dirt. You will need to find a convenient spot to mount the switches, probably on the actuator or nearby. You arrange the switches so that the actuator switches them on at each end of it's travel.

What might be even easier to set up is three switches that indicate the positions of the wing since the up & down positions of the wing are essentially the same as the actuator's limits. The middle switch indicates the neutral position and you just need to adjust the switch positions on the bracket to fine-tune the wing position.

The switches will be connected to three digital input pins on the MCU and the software will use the switch inputs to know when the actuator is in the right position.

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Thanks for the reply overkill,
I had initially thought i could go about it that way as it seemed straight forward and simple. It might be tricky to make up a mounting bracket to house the microswitches. I could have a small tab as such on the connecting rod from the actuators which as you say, trips the limit switches one by one. One difficulty is that the movement of the actuator is only 50mm so the switches would need to be mounted quite accurately.
Would anything else be required other than the limit switched and an MCU which can take 5 inputs?

Not much; the main items will be a couple of relays (or a single DPDT relay) and a simple circuit to drive them as an MCU output doesn't have the capacity to drive a relay directly. Alternatively, you can use an 'H bridge' which essentially does the same job as the relays but its all electronic with no moving parts. You will also need a DC to DC power supply to drop the car's 12 volts down to 5V or 3.3V for the MCU. almost all that stuff is "off the shelf", I or the other furum members can probably whip up a circuit and a shopping list if you need it.

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Originally Posted by overkill

Not much; the main items will be a couple of relays (or a single DPDT relay) and a simple circuit to drive them as an MCU output doesn't have the capacity to drive a relay directly. Alternatively, you can use an 'H bridge' which essentially does the same job as the relays but its all electronic with no moving parts. You will also need a DC to DC power supply to drop the car's 12 volts down to 5V or 3.3V for the MCU. almost all that stuff is "off the shelf", I or the other furum members can probably whip up a circuit and a shopping list if you need it.

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That sounds great, if I could see what I actually need it would be easier to work from and also easier to approach lectures in college if I need help as then I'd have something to work with. Really appreciate the help

No Problems, I need a bit of a break from robots today. Do you prefer to control the motor with relays or with electronics. The main differences are that the relays will be a bit cheaper but will need more custom wiring. Using a solidstate H bridge might be a bit more compact as it can fit right on the arduino board

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Originally Posted by overkill

No Problems, I need a bit of a break from robots today. Do you prefer to control the motor with relays or with electronics. The main differences are that the relays will be a bit cheaper but will need more custom wiring. Using a solidstate H bridge might be a bit more compact as it can fit right on the arduino board

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This is a break? haha

Correct me if I'm wrong anywhere here!

Thats 2 options then:
1. Relays using physical contact as feedback as such? Seems fairly simple to set the limits of movements/set points
2. H bridge, how are the limits of movement set? and the set points, this is where my total lack of knowledge towards electronics is blatantly obvious!

But in both cases i need:
1. DC to DC power supply
2. Arduino

Any ideas of a very vague cost to get this system up and going? Projects cost about €300 so far

The motor drive with relays or an H-bridge is completely separate from the position sensing, with the MCU in the middle to take the position and driver switches and translate that into turning the motor in the right direction. All the relays (or H-bridge) does is power the motor; they don't have anything to do with feedback.

The DC supply would just be 3 or 4 small components to step the 12V down to 5V; they can be soldered onto a small piece of veroboard with basic skills or a pre-built item can be sourced (we call them a 'BEC' for battery eliminator circuit). Since the project has few inputs and outputs, you really only need the most basic Arduino board probably the Arduino Uno at around 18 pounds. I don't know many suppliers in the UK, so unless you have a favourite, I will use Element 14 or RS-Components as a reference.

Before I go designing the wrong solution, are you up for any electronics soldering? The relay option is looking cheaper than than the H-bridge but its more work to construct, while the bridge is very plug & play.

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Originally Posted by overkill

Before I go designing the wrong solution, are you up for any electronics soldering? The relay option is looking cheaper than than the H-bridge but its more work to construct, while the bridge is very plug & play.

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Hi again overkill,
I would be able to solder no problem but i dont have much time so plug and play is the way to go!

chatting to a lecturer today in college and he reckon arduino is the way to go, as it will be the most straight forward option for me so i dont get too tied up in the electronics. also recommended using a motor shield, im heading out to a supplier today to hear what they have to say.

What do you think of the arduino and motor shield option?

Got the arduino uno and motor shield.
This motor rus at 32A at max load and 72A so i think i will need to operate a relay with the arduino?
any ideas?