Abstract: A motion restrictor device is operable to be worn with a protective helmet to reduce the risk of head or spine injury caused by injurious movement of the helmet. The device includes a helmet-engaging component supported on a harness. The component presents helmet-engagement surfaces positioned on opposite sides of the neck of the user. The component is operable to yieldably bias each of the helmet-engagement surfaces toward the helmet when the device is worn, such that contact with the helmet is maintained as the helmet-engagement surface shifts through a range of motion. The device also includes a brake assembly that restricts shifting of at least one of the helmet-engagement surfaces in response to injurious movement of the helmet.

Abstract: A motion restrictor device is wearable with a helmet to reduce the risk of head or spine injury caused by injurious movement of the helmet. The device includes a harness wearable by a user of the helmet and a helmet-engaging component supported on the harness. The helmet-engaging component presents laterally spaced apart, fore-and-aft extending helmet-engagement surfaces positioned on opposite sides of the neck of the user when the device is worn.

Abstract: A motion restrictor device is operable to be worn with a protective helmet to reduce the risk of head or spine injury caused by injurious movement of the helmet. The device includes a helmet-engaging component supported on a harness. The component presents helmet-engagement surfaces positioned on opposite sides of the neck of the user. The component is operable to yieldably bias each of the helmet-engagement surfaces toward the helmet when the device is worn, such that contact with the helmet is maintained as the helmet-engagement surface shifts through a range of motion. The device also includes a brake assembly that restricts shifting of at least one of the helmet-engagement surfaces in response to injurious movement of the helmet.

Abstract: A motion restrictor device is operable to be worn with a protective helmet to reduce the risk of head or spine injury caused by injurious movement of the helmet. The device includes a helmet-engaging component supported on a harness. The component presents helmet-engagement surfaces positioned on opposite sides of the neck of the user. The component is operable to yieldably bias each of the helmet-engagement surfaces toward the helmet when the device is worn, such that contact with the helmet is maintained as the helmet-engagement surface shifts through a range of motion. The device also includes a brake assembly that restricts shifting of at least one of the helmet-engagement surfaces in response to injurious movement of the helmet.

Abstract: A motion restrictor device is operable to be worn with a protective helmet to reduce the risk of head or spine injury caused by injurious movement of the helmet. The device includes a helmet-engaging component supported on a harness. The component presents helmet-engagement surfaces positioned on opposite sides of the neck of the user. The component is operable to yieldably bias each of the helmet-engagement surfaces toward the helmet when the device is worn, such that contact with the helmet is maintained as the helmet-engagement surface shifts through a range of motion. The device also includes a brake assembly that restricts shifting of at least one of the helmet-engagement surfaces in response to injurious movement of the helmet.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed. The device includes a strut having a pair of relatively moveable strut members. One of the strut members is associated with the helmet, and the other strut member is associated a harness assembly. The device also includes a brake assembly, with the assembly providing a plurality of arrest rates. Each of the arrests rates corresponds with a rate of relative motion (or acceleration) and a corresponding force experienced between the pair of strut members.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor or a predetermined amount of or rate of acceleration being sensed by an acceleration sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.

Abstract: A protective helmet, which includes a motion restrictor device, is disclosed which has at least one strut member associated with the helmet and a harness assembly, and the at least one strut member includes a locking assembly associated with the strut member, which upon a predetermined force being sensed by a force sensor, stops substantially all relative motion between the ends of the strut member and the predetermined force is substantially transferred from the helmet to the harness assembly.