Systems and methods for calculating motor position, inertia and rest position in sensorless brushed dc motor control systems

A system comprising:

• a motor driver module configured to measure current supplied to a motor;
• and
• a motor position determination module configured to:
• determine a first position of the motor at a first time when power supply to the motor is initially discontinued based on ripples in the current supplied to the motor during a first period before the first time;
• and
• determine a second position of the motor at a second time when the motor stops rotating after power supply to the motor is discontinued based on the first position of the motor and a rotational speed of the motor at the first time.

A system comprising:

• a motor driver module configured to:
• measure current supplied to a motor;
• and
• measure current induced by the motor after power supply to the motor is discontinued;
• and
• a motor position determination module configured to:
• determine a position of the motor when power is supplied to the motor based on ripples in the current supplied to the motor;
• and
• determine the position of the motor after power supply to the motor is discontinued based on ripples in the current induced by the motor.

A system comprising:

• a motor control module configured to supply power to a motor of a seat assembly to rotate the motor from a current position to a target position;
• a motor position determination module configured to:
• determine a rotational speed of the motor based on ripples in current supplied to the motor;
• and
• determine an inertia of the seat assembly based on the rotational speed of the motor and a mass of the seat assembly;
• and
• a target motor stop position module configured to determine when to discontinue power supply to the motor based on the target position of the motor and the inertia of the seat assembly.