University Race Car

Helping Friends Re-Wire A Race Car

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Because  of my years of experience working on cars, specifically auto-electrically, my friends have gotten me involved in a project at my university.

The car is intended to be entered into a hill climb racing event, but unfortunately there are a few issues that need resolving first. The thing with modern cars, is that you cannot just change things anymore. Modern cars are essentially like a moving office blocks of computers, having their own networks to communicate with each-other. Some new vehicles, such as some Land Rovers, don't even come with a dip stick anymore !! You have to use a diagnostics machine, sometimes worth up to £2000 just to check the oil, and have to measure how much you put it.

The computers control almost everything. This includes engine timing, fuel amount, braking pressures, lights and there are sometimes even separate computers in each door just for the windows and locking !!

To work with new cars you basically need an essential bit of kit, and that is a Auto-Diagnostics System. Luckily from my experience using them and having relatives involved in the designing of these tools, i have a reasonable amount of knowledge on how to use them and how they work. Below is a video, shown again later, showing some of this communication.

The main problem with this car is due to its ABS system. The Automatic Braking System is used to better control the car during braking. Sensors around the car determining how fast the car is moving, looking at the speeds of each wheels separately, sometimes also using accelerometers to detect how the car is moving. This can be used to detect if a car is at a slide, if the wheels are just spinning and other situations where the car may be slipping on the road.

 

Using ABS gives the car "Anti-Lock Braking". The purpose of this is to control how much braking pressure is applied to each wheel, and to have it pulse, stopping the wheels from just locking up causing the car to skid. This allows for more efficient and safer handling and breaking of the car, and where other features like traction control can be implemented.

The issue of this car is in two areas. Area 1 is where a previous racing team owned the car and fitted in some form of live monitoring system. Such systems can record data as well as send it to staff while watching a car race. This can be used to help give advice to the driver in certain conditions or detect imperfections in braking, tire pressure or even needing modifications done to the steering tracking ect...

 

This system was removed, but was tapped into the cars CAN networks, the Controlled Area Network busses for communication throughout the car, to read from the many of sensors around the car. Because it was removed it has left the main loom a tad messy, which makes it hard to work with and may not pass tests in order to qualify it for racing, especially when it comes to fire dangers.

The second problem is that the car has been upgraded with an aftermarket braking system, that is not using the ABS. When a car detects anomalies that may put the driver in danger it goes into a so called "Limp Mode", this restricts the power to the car to a minimum, possibly even shutting down cylinders in the engine to the car can safely "Limp" home without stressing the car anymore, preventing any more damage or a crash at speed. Now this isn't good for a race car that needs to restart after every time the brakes are applied, to prevent it from staying at 10-30 MPH, hence why im involved.

By using CAN hacking, i can remove systems the car doesn't need anymore to lighten the car, but also record and manipulate CAN signals/messerges to replace them too. Using special software, hardware and techniques i should be able to record the message between computers, working out what is needed to keep the car running smoothly and safely. The car would be safe without ABS as it is a propper racing spec system fitted, its not much diferent to driving a classic car apart from. It has better breaking, just niot coimputer controlled.

In theory i should be able to replace the ABS with a microcontroller, such as an Arduino with a CAN shield interface, by using the sensors to tell when the engine needs to apply engine braking if needed, but more importantly making it think it is ok and doesn't need to go into limp mode.  This may also be needed when the suspension and weight of the vehicle is changed. Below you can see an example of such CAN Hacking software, using the additional hacking simulator feature for practice, that i have bought

By using the correct list of commands you can alter what you display read from the OBDII (the port made industry standard on road vehicles, required on all cars legally since 1995). Below you can see that everything that is not constantly changing is removed from the screen as it is seen as "not important". The cars system works by continuously sending signals thousands of times a minute, such as telling the highlight to be on. In Fact if you look at some new cars from a video you can see a flicker in the lights from the frame rate of the camera not matching that of the lights, similar to that with a old CRT TV.

Using software to record the changing messerges (RED shows changing values within changing lines), and a tripod with a camera with us filming what buttons we are pressing, and pedals, wheels spinning ect.... We can match up side by side what code means what, as everytime we change something we should see that code appear. Depending on what is required we can use this to make a replacement unit to replace the ABS for much better performance when racing, if needed we can have it piggy back, to interrupt and change messages passively so certain messages never hit the engine or dash. This way we get every benefit of the ABS, and just change the codes that put the car into limp mode live, everytime the car mistakenly thinks something is wrong. This would possibly also mean doctoring the signals going to the ABS too, but that's totally feasible with the use of a rolling road and some road tests with a laptop plugged in.

Not just this help rectify the issue with the modifications, but is also helps with issue 1 as we can remove any of the many computers not needed in the car. This will leave us with only the wires we need - making modifying the car electrically much easier. This will also drastically reduce weight and these cars are flooded with metal cased computers and many many wires.

From one of many rewiring jobs my dad has done, about 3 bin bags of wires were removed. This was from a jag engine put in an old chevy truck for a hot rod. Let's just say all that metal wire adds up in weight very fast !

After we are left with the only wires we need, they can be routed in the most optimal places, and hidden from any danger. With the interior out you will find big streams of wires in all sorts of places from on the floor, each side of the car and even sometimes the roof. We can reduce this to a much more direct and compact rout in fire resistant tape and trucking tubing. This will make the insides tidier and much much safer. 

Depending on what the car needs, even lights like indicators can be removed, the windows motors and other computers can even be sold to help fund other features that want to be added also.