Each temperature level limits the motor current: level 1 = 50% current, 2 = 25% current, 3 = 12.5% current, 4 = 0% current. The motor has four levels of response to rising temperatures. If the motor reaches its temperature limit, performance is automatically reduced to ensure no damage occurs. If a motor is approaching an unsafe temperature, the user gets a warning. Finally, to make sure the motor lasts, the internal temperature is monitored. The 2.5A limit essentially removes the undesirable region of the motor’s performance curve, ensuring users do not unintentionally create stall situations. Limiting stall current eliminates the need for automatic resetting fuses (PTC devices) in the motor, which can cause unintended motor outages. Stall current is limited to 2.5A to keep heat under control without affecting peak power output. This means the motor will perform the same for every match and every autonomous run, regardless of battery charge or motor temperature. The motor runs internally at a slightly lower voltage than the battery’s minimum voltage, and the motor’s power is accurately controlled to +/-1%. One of the (11W) V5 Smart Motor’s most unique capabilities is completely consistent performance. “Consistent motor performance is a game changer” The encoder values are provided in the chart below per each gear cartridge. The resolution of the encoder is determined by the internal gear cartridge of the motor. The rotation is divided into a number of steps or “ticks” which provides feedback as to the amount a shaft has turned. These measure the amount of rotation of the shaft socket. Raw control still has the same rpm limits, current limits, and voltage maximum that keep the motor’s performance identical.Īdditional control of the V5 Smart motor is achieved by internal encoders. The motor’s PID values are pre-tuned by VEX for excellent performance across all operating conditions.Īdvanced users can bypass the internal PID and take direct control with raw, unaltered PWM (pulse-width modulation) control. PID is internally calculated at a 10 millisecond rate. The microcontroller runs its own PID (proportional-integral derivative) with velocity control, position control, torque control, feedforward gain, and motion planning similar to industrial robots. The motor’s internal circuit board has a full H-Bridge and its own Cortex M0 microcontroller to measure position, speed, direction, voltage, current, and temperature. The motor's shaft socket can accommodate 1/8" Drive Shafts as well as 1/4" High Strength Shafts. An internal gear cartridge is user changeable for output gear ratios of 6:1, 18:1, and 36:1. Plastic gears are used in the low-load, high-speed locations for smooth and efficient operation. Metal gears are used in all high-torque locations for strength. The (11W) V5 Smart Motor’s internal gear design has to withstand all the motor’s power, and the abuses of external forces coming into the motor from loaded arms and robot momentum.
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