A vehicle body lower structure includes: an undercover having an opening and a first fixing portion disposed around the opening; a cover member having a second fixing portion and detachably attached to the undercover to close the opening; and a fixing member configured to detachably attach the second fixing portion to the first fixing portion, the fixing member being fixed to the first fixing portion and the second fixing portion from a lower side of the undercover. The undercover includes a general portion and the first fixing portion, and at least the general portion and the first fixing portion are made of a board member having a constant thickness. The second fixing portion of the cover member is thicker than the board member. The second fixing portion of the cover member is located over an upper surface of the undercover.

A reinforcement structure for protection of a vehicle power source, e.g. a battery pack or a fuel cell. The reinforcement structure extends in a first, a second and a third direction (D.sub.1, D.sub.2, D.sub.3) being perpendicular to each other, wherein an extension of the reinforcement structure is at least 5 times larger in the first and second directions than in the third direction. The reinforcement structure has a tapered shape as seen in a plane spanned by the first and second directions. The present disclosure also relates to a reinforcement unit, a vehicle power source arrangement and a vehicle utilizing such reinforcement structure.

A reinforcement structure for protection of a vehicle power source, e.g. a battery pack or a fuel cell. The reinforcement structure extends in a first, a second and a third direction (D.sub.1, D.sub.2, D.sub.3) being perpendicular to each other, wherein an extension of the reinforcement structure is at least 5 times larger in the first and second directions than in the third direction. The reinforcement structure has a tapered shape as seen in a plane spanned by the first and second directions. The present disclosure also relates to a reinforcement unit, a vehicle power source arrangement and a vehicle utilizing such reinforcement structure.

A four-wheel chassis comprising a body, and a front wheel assembly and a rear wheel assembly detachably coupled to the body. After detached from the body, one of the front wheel assembly and the rear wheel assembly independently moves as a two-wheel chassis. The one of the front wheel assembly and the rear wheel assembly is connected to a wheel driving controller that controls wheels of the two-wheel chassis.

A chassis frame includes a side rails and cross-members that intersect at a number of intersection points, which collectively define a chassis frame with front and rear portions that define a main support section and an integral engine support section. Each side rail includes a top plate, a bottom plate, and first and second side plates extending between the top and bottom plates. The first and second side plates each have a first end coupled to a bottom surface of the top plate and a second end coupled to the top surface of the bottom plate. Each cross-member includes a top plate, a bottom plate, and first and second side plates extending between the top plate and bottom plates. The first and second side plates each have a first end coupled to a bottom surface of the top plate and a second end coupled to the top surface of the bottom plate. A plurality of gusset portions is formed between the top plates of the side rails and cross-members at each intersection point.

A chassis frame includes a side rails and cross-members that intersect at a number of intersection points, which collectively define a chassis frame with front and rear portions that define a main support section and an integral engine support section. Each side rail includes a top plate, a bottom plate, and first and second side plates extending between the top and bottom plates. The first and second side plates each have a first end coupled to a bottom surface of the top plate and a second end coupled to the top surface of the bottom plate. Each cross-member includes a top plate, a bottom plate, and first and second side plates extending between the top plate and bottom plates. The first and second side plates each have a first end coupled to a bottom surface of the top plate and a second end coupled to the top surface of the bottom plate. A plurality of gusset portions is formed between the top plates of the side rails and cross-members at each intersection point.

An underbody structure for a motor vehicle has: at least one underbody panel; and at least one air guide. The air guide is assigned to the underbody panel and has at least one separation edge for bringing about a flow separation. The air guide is passively pivotable back at least in sections behind a plane formed by a carriageway-side outer side of the underbody panel such that the separation edge is capable of yielding upon contact with an obstacle in order to avoid damage.

An underbody structure for a motor vehicle has: at least one underbody panel; and at least one air guide. The air guide is assigned to the underbody panel and has at least one separation edge for bringing about a flow separation. The air guide is passively pivotable back at least in sections behind a plane formed by a carriageway-side outer side of the underbody panel such that the separation edge is capable of yielding upon contact with an obstacle in order to avoid damage.

The present disclosure provides a chassis comprising a frame, two hanging units symmetrically provided at both sides of the frame, and a front guiding wheel and a rear universal wheel provided below the frame, wherein each of the hanging units comprises a mounting rack fixedly connected to the frame, a hanging rack slidably connected to the mounting rack, and a driving wheel rotatably connected to the hanging rack, and the front guiding wheel is provided with a first driving motor, and the driving wheel of each hanging unit is driven by a second driving motor, and wherein a closed loop speed control system is formed between the first driving motor and both second driving motors, such that a rotational angle of the front guiding wheel is adjustable via the first driving motor when revolving speeds of both second driving motors are changed.

The present disclosure provides a chassis comprising a frame, two hanging units symmetrically provided at both sides of the frame, and a front guiding wheel and a rear universal wheel provided below the frame, wherein each of the hanging units comprises a mounting rack fixedly connected to the frame, a hanging rack slidably connected to the mounting rack, and a driving wheel rotatably connected to the hanging rack, and the front guiding wheel is provided with a first driving motor, and the driving wheel of each hanging unit is driven by a second driving motor, and wherein a closed loop speed control system is formed between the first driving motor and both second driving motors, such that a rotational angle of the front guiding wheel is adjustable via the first driving motor when revolving speeds of both second driving motors are changed.