Electronic throttle control of snowmobile with two-stroke internal-combustion engine

An electronic throttle-control system for a snowmobile, comprising:

• an electronic control unit (ECU) including a processor and a memory device storing at least one throttle-control translation map;
• a throttle-input sensor in electrical communication with the ECU and configured to sense an input from an operator-actuated throttle device;
• a 2-stroke internal-combustion engine, including:
• an electronic throttle-valve actuator in electrical connection with the ECU and having an actuator motor and gear train;
• a throttle body for controlling airflow to one or more combustion chambers of the 2-stroke internal-combustion engine, the throttle body defining a first throttle bore and a second throttle bore;
• a first throttle valve in the first throttle bore and a second throttle valve in the second throttle bore;
• and
• a throttle valve control shaft coupled to the first throttle valve and the second throttle valve, and to the gear train, such that movement of the actuator motor and gear train causes the throttle valve control shaft to rotate and move the first and second throttle valves;
• a throttle-position sensor in electrical communication with the ECU and configured to sense an actual position of the first and second throttle valves;
• wherein the ECU is configured to receive a signal representing a throttle-position input from the throttle-input sensor and to determine a throttle-demand position corresponding to a position of the first throttle valve in the first throttle bore and a position of the second throttle valve in the second throttle bore, based on the throttle-position input and throttle-control translation map, and
• wherein the ECU is configured to:
• limit a throttle-demand position based on at least one of ground speed, user-selected limit parameters, or fault-state limit positions;
• and
• transition from the idle control mode to a translation-map control mode when:
• the throttle-demand position exceeds a predetermined idle throttle threshold, and
• the engine speed exceeds a predetermined idle engine-speed threshold.