Propulsion: Hydrojet
Overview
To enable the Hydrojet controller, the register HYDROJET_CONTROLLER_ACTIVE needs to be set to 1.
Configurations
Single hydrojet
HYDROJET_CONTROLLER_STEERING_MODE = 2
Both left and right steering and throttle outputs behave the same, choose one.
Dual Hydrojet
HYDROJET_CONTROLLER_STEERING_MODE = 1
It is necessary to set up both the right and left hydrojets, each with its own steering and throttle output. The throttle settings must be configured accordingly (see the section "Throttle Settings" below).
This applies to catamaran configurations as well.
Boosters
Optional booster hydrojets (without steering or reverse) can be addressed.
The register HYDROJET_CONTROLLER_BOOSTER_ENABLE_INPUT take an input address with a PWM value from 1000 µs to 2000 µs. It acts as a switch to either enable or disable the boosters. The booster throttle while cruising forwards are calculated upon the steerable hydrojets.
During reverse thrust, the boosters are disabled (addressed with 1000 µs PWM).
Catamaran
Catamaran configurations use the same settings as V-Hull configurations. Each hull takes one hydrojet, either the left or right one.
Throttle settings
Register: HYDROJET_CONTROLLER_THROTTLE_MODE
Mode 0: The throttle channel is centered at 1500 µs. Values towards 1000 µs are considered reverse, and values towards 2000 µs are considered forward. The reversing bucket will extend when the channel PWM is under 1500 µs.
Mode 1: The throttle channel is proportional to the motor RPM, ranging from 1000 µs to 2000 µs. The reversing bucket is extended through the switch at the register HYDROJET_CONTROLLER_REVERSE_INPUT.
Reverse
An incorrect setup of the reverse thrust power can damage the reverse bucket, and in the worst cases, it can even tear apart the hydrojet nozzle!
Hydrojets can be very powerful. To avoid the risk of damage or destruction of the reversing bucket, the RPM of the motors needs to be kept low during reverse thrust; we suggest around 5% of the total available power.
This parameter is set through the register HYDROJET_CONTROLLER_REVERSE_MAX_PWM, which accepts any value between 1000 µs and 2000 µs.
Registers
| Register | Values | Function |
| HYDROJET_CONTROLLER_ACTIVE | 0,1 | Enables the controller |
| HYDROJET_CONTROLLER_STEERING_INPUT | Register address | PWM input steering |
| HYDROJET_CONTROLLER_THROTTLE_INPUT | Register address | PWM input throttle |
| HYDROJET_CONTROLLER_TRAVERSE_INPUT | Register address | PWM input traversing |
| HYDROJET_CONTROLLER_REVERSE_INPUT | Register address | Deploys the reversing bucket |
| HYDROJET_CONTROLLER_BOOSTER_ENABLE_INPUT | Register address | Enables the boosters |
| HYDROJET_CONTROLLER_REVERSE_MAX_PWM | 1000-2000 | Max PWM when reversing bucket deployed |
| HYDROJET_CONTROLLER_CRUISE_MAX_PWM | 1000-2000 | Max forward cruise PWM |
| HYDROJET_CONTROLLER_THROTTLE_MODE | 0,1 | Throttle mode |
| HYDROJET_CONTROLLER_STEERING_MODE | 0,1,2 | Steering mode |
| HYDROJET_CONTROLLER_OUTPUT_LEFT_RPM | 1000-2000 | Left motor output |
| HYDROJET_CONTROLLER_OUTPUT_LEFT_REVERSE | 1000-2000 | Left reversing bucket output |
| HYDROJET_CONTROLLER_OUTPUT_LEFT_STEERING | 1000-2000 | Left steering output |
| HYDROJET_CONTROLLER_OUTPUT_RIGHT_RPM | 1000-2000 | Right motor output |
| HYDROJET_CONTROLLER_OUTPUT_RIGHT_REVERSE | 1000-2000 | Right reversing bucket output |
| HYDROJET_CONTROLLER_OUTPUT_RIGHT_STEERING | 1000-2000 | Right steering output |
| HYDROJET_CONTROLLER_OUTPUT_BOOSTER_RPM | 1000-2000 | Booster motor output |