Driver Training

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You will encounter many driving obstacles at the Baja SAE competition, and these are some of the important ones to train for. Note that driving the car aggressively with high amounts of slip on the tires in maneuvers like the slalom, hair-pin turn, and skid pad testing will wear the tires heavily. Plan to purchase spare tires to use for practice and make sure to have good tires for competition.


Handling Maneuvers[edit]

The following maneuvers have in common that they are usually flat or slightly uneven ground, but are not special to off-road obstacles like rocks and logs

Slalom[edit]

Expect a slalom on every Land Maneuverability course. Usually it is set up with cones or other obstacles set around 12-15 feet apart. Start your drivers training on a row of at least 4 cones on dirt/gravel set at a distance of 20 feet apart. Teach them to use a fluid motion working the steering wheel left and right, and to begin the turn before each cone, not immediately after. Imagine a sinusoidal input to the steering wheel. Once the driver is able to take the slalom at speed you can decrease the distance between cones. Repeat the exercise until the cone spacing is as tight as the driver can possibly manage. For the tightest slalom, the driver will have to use techniques to drift the rear tires, and the suspension should be set up for the appropriate roll stiffness to achieve that.

Once the driver can execute a single pass of the slalom, consider training for the hair-pin turn at the last cone and continuing the slalom in the opposite direction. Also, practice entering the slalom from both sides so your training is balanced between left-hand and right hand turns. A video with driving instruction for regular cars on asphalt, but the principles are the same: https://youtu.be/0rIH61q23O8?t=37

Hair-pin[edit]

Set a cone at a distance of at least 20 feet and direct the driver to accelerate at full speed towards it and make the turn as tight and fast as possible and return. You can set two cones and have the driver run this obstacle back and forth, or do a figure-of-8 maneuver to practice both left and right hand turns. For the tightest hair-pin turn, the driver will have to use techniques to drift the rear tires, and the suspension should be set up for the appropriate weight transfer to achieve that.

Drifting[edit]

To drift a turn the driver must modulate the accelerator pedal so that the engine applied torque on the rear tire(s) is high enough to increase the tire slip for a high, but controllable amount of vehicle yaw. This way of turning with high tire slip can make a car maneuver around an obstacle at a tighter radius than the Ackermann steering radius would allow at low speed. Because the Baja car has a very low power-to-weight ratio, you generally must have enough roll stiffness in the rear in order to transfer all or most of the tractive effort to the outside tire in a corner in order to achieve this slip. That is why the old swing-arm cars with inherently high roll-stiffness in the back could drift so easily, but at the cost of other handling characteristics like higher speed steady state cornering.

Limit Cornering[edit]

To practice cornering at high speed, set up a skid pad on dirt/gravel. Place cones or spray paint a line in a circle and instruct the driver to drive outside this circle at the vehicle's max speed. Repeat with several different radius circles. The driver should get feedback from the steering wheel as well as a sense of the vehicle's yaw as it approaches the tire limit. Depending on the tires and ground surface, the transition from low speed cornering to limit cornering and beyond may be forgiving or unforgiving. Unforgiving tires will give little indication that they are approaching the limit of slip until it is too late and the car is spinning. Instruct the driver to get a familiarity with using the accelerator pedal to make steering corrections to the car by increasing/decreasing rear tire slip... it is usually best not to work the steering wheel much once you are in the turn. Add accelerator pedal to increase your radius, and ease off the accelerator to decrease it.

A land maneuverability course will have some large sweeping radii that you should be comfortable taking at the maximum speed your vehicle allows. More importantly, the endurance race course will have many large radius turns that should be taken as fast as possible, within the driver's skill.

Straight Line Accel/Braking[edit]

Train drivers for digital driving. In straightaways there is little risk of losing control from heavy acceleration or braking, so teach drivers to have comfort going to full throttle soon after exiting a corner and using heavy braking right before an obstacle. Teach the drivers to pump the brakes during a skid if the car starts to get sideways (like you used to in the days before Anti-lock brakes). The all-on or all-off nature of using the brakes and accelerator this way is why it is called 'digital driving.' This obviously maximizes time at top speed and top acceleration, and is an aggressive driving style you need to use in racing.

Suspension Maneuvers[edit]

Logs, RR ties, pipes[edit]

Rocks[edit]

Jumps[edit]

Woops[edit]

https://www.youtube.com/watch?v=xFHvuY-A6rs