Electronic device for determining an emergency stopping trajectory of an autonomous vehicle provided with an autonomous driving module, the autonomous vehicle being able to store, beforehand, at least one predefined trajectory of movement comprising a plurality of successive reference vectors (V 1, V 2, V 3, V 4, V 5) respectively associated with different successive segments (P 1, P 2, P 3, P 4, P 5) of movement of the autonomous vehicle, characterized in that the electronic device for determining an emergency stopping trajectory is configured to determine an emergency stopping trajectory comprising a plurality of successive emergency stopping vectors (V E1, V E2, V E3) each associated with a different segment (P 2, P 3, P 4) of a part of the successive segments of the predefined trajectory, from at least for each emergency stopping vector (V E1, V E2, V E3): ∘ a stored last actual movement vector of the autonomous vehicle, ∘ the predefined movement trajectory of the autonomous vehicle, and ∘ a stored last location datum of the autonomous vehicle, and delivered by at least one sensor of the autonomous vehicle, the electronic device for determining an emergency stopping trajectory being automatically activable in the presence of an emergency stopping instruction, and comprises: - a module for calculating at least one automatic movement setpoint of the autonomous vehicle in order to follow said emergency stopping trajectory, - an emergency steering module capable of steering the autonomous vehicle according to said at least one setpoint an emergency stopping instruction causing the activation of the module for calculating. characterized in that the electronic device for determining an emergency stopping trajectory is configured to determine an emergency stopping trajectory comprising a plurality of successive emergency stopping vectors (V E1, V E2, V E3) each associated with a different segment (P 2, P 3, P 4) of a part of the successive segments of the predefined trajectory, from at least for each emergency stopping vector (V E1, V E2, V E3): ∘ a stored last actual movement vector of the autonomous vehicle, ∘ the predefined movement trajectory of the autonomous vehicle, and ∘ a stored last location datum of the autonomous vehicle, and delivered by at least one sensor of the autonomous vehicle, ∘ a stored last actual movement vector of the autonomous vehicle, ∘ the predefined movement trajectory of the autonomous vehicle, and ∘ a stored last location datum of the autonomous vehicle, and delivered by at least one sensor of the autonomous vehicle, the electronic device for determining an emergency stopping trajectory being automatically activable in the presence of an emergency stopping instruction, and comprises: - a module for calculating at least one automatic movement setpoint of the autonomous vehicle in order to follow said emergency stopping trajectory, - an emergency steering module capable of steering the autonomous vehicle according to said at least one setpoint - a module for calculating at least one automatic movement setpoint of the autonomous vehicle in order to follow said emergency stopping trajectory, - an emergency steering module capable of steering the autonomous vehicle according to said at least one setpoint an emergency stopping instruction causing the activation of the module for calculating.