In combination with a vehicle and a closure, one or more lockdown regions disposed between the closure and the vehicle body, the one or more lockdown includes a device including an active material disposed in operative communication with the closure and the vehicle body, wherein the active material includes a shape memory alloy, a magnetic shape memory material, a shape memory polymer, a magnetorheological fluid, an electroactive polymer, a magnetorheological elastomer, an electrorheological fluid, a piezoelectric material, or combinations comprising at least one of the foregoing active materials; and an activation device coupled to the active material, the activation device being operable to selectively provide an activation signal to the active material and effectuate a change in a dimension, a shape, and/or a flexural modulus property of the active material, wherein the change in the dimension, a shape, and/or flexural modulus of the active material locks down or releases the closure from the vehicle. Such active materials include shape memory alloys, magnetic shape memory alloys, electroactive polymers, shape memory polymers, magnetorheological fluids, magnetorheological elastomers, electrorheological fluids, and piezoelectric materials. Also provided herein are methods for selectively stiffening a closure hingeably attached to a vehicle body.