ControllerStates

RcCat Controller States

The RcCat::Controller knows 5 different state types, which are automatically chosen depending on sensor data.

enum DriveStateType {
     normal   = 1,
     falling  = 2,
     elevated = 3,
     jumping  = 4,
     external = 5
     };

Depending on the status of the RcCat::Controller, either the commands from the remote control are passed (directly or modified) to the steering servo or the speed controller, or the control of the car is completely taken over by the RcCat::Controller. Below is a minimalistic overview of the different drive states.

Normal

The DriveStateType::normal is always active when the car is sufficiently close to the ground and no external commands are triggered. There is a so-called saveMode which capps the the maximum speed with the data of the rpm sensor. This saveMode can be enabled/dissabled by giving full trottle/break once the car is elevated. This helps to easily pass the car to curious kids. Outside of the saveMode the pitch data of the gyro is used to reduce the throttle to give maximal acceleration without wheelies or rollovers.

Elevated

The DriveStateType::elevated is entered when the ground distance is high and the speed of the car almost zero. In this state the car steers straight ahead and stops the main motor to prepare for the possible upcoming DriveStateType::falling.

Falling

Once the car is in the DriveStateType::falling the main is used to bring the car the level befor reaching the ground. This is done via a small neural network. The next state is DriveStateType::normal once the car reaches the ground.

Jumping

The DriveStateType::jumping is entered when the ground distance is higher than a few centimeters and the speed of the car is sufficiently high. This is done by the same neural network. In the past, two different PID controllers were used for this. The controler goes back to DriveStateType::normal once the groud distance is small again.

External

The DriveStateType::external can be entered by sending a command to the microcontroller over the serial bus. The state is only enterd if the radio input was close to zero for the last 5 seconds, and goes back to DriveStateType::normal if a radio signal with different drive commands are received.