ABS mods? have they been done

[Kejtar]

Ok I understand your fear but it will only be operational at low speeds off road when on road it will be just like a regular bypassed sysem (safe)

OK, same rule applies: you want to design a system for under $1k (from the sounds of it for way under less than $1k) and get the same results that Range Rover did? Please remember that what you do on the trail might put others in danger as well.

 

[xj trenton]

OK, same rule applies: you want to design a system for under $1k (from the sounds of it for way under less than $1k) and get the same results that Range Rover did? Please remember that what you do on the trail might put others in danger as well.

I was just wondering if anyone has done this the equipment is the same you apply the brakes and use the valves to release the pressure for the wheel that is not turning untill it is at the same speed as the one turning. This only happens when the system is on. when its off the abs system is locked out and won't effect normal driveing. Ps I have programming back ground and have a friend that is a guru.

 

[jrsxj98]

they 4" lift blocks will stabilize it......

 

[Kejtar]

I was just wondering if anyone has done this the equipment is the same you apply the brakes and use the valves to release the pressure for the wheel that is not turning untill it is at the same speed as the one turning. This only happens when the system is on. when its off the abs system is locked out and won't effect normal driveing. Ps I have programming back ground and have a friend that is a guru.

If you have a programming background than you more than others should realize how tough it would be to make it work the way you want it to.

 

[xj trenton]

If you have a programming background than you more than others should realize how tough it would be to make it work the way you want it to.

tough yes impossible no;D

 

[kubtastic]

If you had some background you'd also know that a PC Laptop is a horrible choice. Go get yourself a development board for a microcontroller so that it runs in real time instead of on Microcrash windows.

 

[xj trenton]

If you had some background you'd also know that a PC Laptop is a horrible choice. Go get yourself a development board for a microcontroller so that it runs in real time instead of on Microcrash windows.[/QUOTE

I'm thinking simple for now linux not microcrash

 

[Kejtar]

I'm thinking simple for now linux not microcrash

Actually Kubtastic is right. That's simple and more stable and the right way to do it.

 

[kubtastic]

okay. Go for it. My experience says that a laptop will give you all the processing you can handle, but...

1) ABS sensors at each wheel transmit an analog signal that requires a clocked microprocessor with ATD converters to analyze. Maybe your laptop has a fast enough input, but good luck debugging it if you can't detect wheel slip. Also, what voltage is it at?
2) Your output is also going to be pulsed and the voltage, who knows. Got any equipment?
3) Programming a traction control system, and then testing it. Testing it a lot, and then validating that it actually is improving your experience and not toasting your brake pads.

I seriously suggest a microcontroller for this job. A simple 2 MHz computer is all it takes to detect wheel slip. It has predictable performance as well.

 

[xj trenton]

okay. Go for it. My experience says that a laptop will give you all the processing you can handle, but...

1) ABS sensors at each wheel transmit an analog signal that requires a clocked microprocessor to analyze. Maybe your laptop has a fast enough input, but good luck debugging it if you can't detect wheel slip. Also, what voltage is it at?
2) Your output is also going to be pulsed and the voltage, who knows. Got any equipment?
3) Programming a traction control system, and then testing it. Testing it a lot, and then validating that it actually is improving your experience and not toasting your brake pads.

I seriously suggest a microcontroller for this job. A simple 2 MHz computer is all it takes to detect wheel slip. It has predictable performance as well.

well have you tried it this. This is why I asked the question I need input so far you have been the most help I did realize I would need an interface of some sort and use the laptop to fine tune the whole system much like the stand alone fuel management systems used to set the peramiters of onboard computers

 

[kubtastic]

I haven't tried it. What I did find in researching this (I had dreams of ABS with a ford rear-end) is that the ABS computer relies on a frequency based signal to detect wheel slip. It's an analog signal that has a slight voltage range thanks to a magnet for a sensor.
The interface you talk about is found within the ABS computer on the XJ now. It's a complicated POS.


Have you also considered this special detail: This system, if successful, would only work for the front axle. The XJ has 3 channel braking. Rear axle braking wouldn't be any more effective than applying the handbrake while spinning.