Worm gear drive unit interface and assembly methods

A system for detachably coupling subassemblies to vehicles or other components is discussed herein. The system can include one or more driveshafts and worm drives to drive fasteners to couple the subassembly to the vehicle. The system can enable drive interfaces located in a substantially conventional location (e.g., located vertically on the bottom of the vehicle) to drive fasteners horizontally into the body or other subassembly. In this manner, fasteners can be hidden and to utilize blind holes in the body of the vehicle. The system can be partially disassembled in situ to enable parts replacement and fastener access in the event of a failure. The system can be used in conjunction with a robotic cart to enable subassemblies to be removed from the vehicle for service and repair. A portion of the system can also act as a portion of, or to reinforce, the crash structure of the vehicle.

BACKGROUND

Conventionally, vehicles are assembled in two main sections: the “body in white” and the chassis. When these assemblies reach a certain stage of completion, the assemblies are “married” to form a substantially complete vehicle subject to final assembly. This marriage is generally done with the body on an overhead crane system that lowers the body onto the chassis (e.g., the drivetrain and other components) from above. The body is then generally attached to the chassis using multiple fasteners inserted from the bottom and tightened.

This configuration requires a great deal of infrastructure. In a production setting, multiple overhead cranes, automated carts, assembly lines, and other heavy machinery is required. In addition, the bolts used to connect assemblies are often visible on the complete vehicle or must be covered with trim (e.g., grommets or plugs) and/or sealed in a separate operation. This requires additional steps and additional components, increasing costs.

DETAILED DESCRIPTION

Examples of the present disclosure relate to systems and methods for assembling and disassembling components in a single operation. In other words, the systems and methods disclosed herein enable components such as, for example, vehicle subassemblies to be installed with fasteners, with the fasteners inserted and torqued in a single operation. The fastening system can also enable the fasteners to be installed using automated systems (e.g., robots and/or automatic torque wrenches), to be substantially hidden from view, and to meet other design criteria (e.g., no fasteners penetrating interior panels).

In some examples, the fastening system can be incorporated into the subassemblies themselves. Thus, the fastening system can be included in a crash structure or subframe, for example, and can enable the crash structure or subframe, along with other components, to be easily attached to another subassembly or the body of the vehicle. The fastening system can also enable these same components to be removed from the vehicle by simply reversing the installation procedure.

In some examples, the system can include one or more worm drives attached to driveshafts and disposed inside a housing. The worm drives can enable a torquing device, such as an automatic torque wrench, to interface with the driveshafts in a substantially conventional manner i.e., vertically from below the vehicle yet rotate fasteners that are disposed horizontally. In this manner, the fasteners can attach one subassembly to another, for example, such as a drive module to a vehicle body, horizontally. This configuration, in turn, can obviate the need for overhead cranes or gantries, among other infrastructure for assembling and disassembling vehicles. In addition, the system can enable the fasteners to be substantially hidden when installed (without additional procedures or parts) and to utilize blind holes, reducing body penetrations, among other things.

For ease of explanation, the systems and methods described below are described in the context of installing and removing drive units from the body of a modular vehicle. One of skill in the art will recognize, however, that these systems and methods are not so limited. Indeed, the systems and methods described herein can be used to assemble and disassemble many different types of components and fasteners without departing from the spirit of the disclosure. The system can be used to fasten transmissions to engines, for example, to install accessories on engines, or to couple and decouple other types of subassemblies and components. Generally, such a system may be employed for any removable subcomponent in a larger assembly.

As mentioned above, conventional vehicle assembly lines generally assemble vehicles in one or more subassemblies that are ultimately brought together to form a completed vehicle. Many vehicles are assembled as a “body in white” and a chassis. The body in white refers to the sheet metal components of the vehicle that generally form the body once they have been welded together. The chassis can comprise, for example, a frame, or multiple sub frames, the suspensions components, engine and transmission, exhaust system, and other components. At a predetermined stage of completion, the body in white and the chassis are brought together, generally using a large overhead conveyor system, and bolted, welded, and/or glued to each other.

This operation, which is commonly referred to as the “marriage,” requires significant capital investment. In other words, the chassis is typically riding along a large conveyor or assembly line, or on a robotic cart, while the body in white is generally supported by an overhead crane or gantry system. The conveyor and gantry must then be precisely aligned to enable the two main components to be brought together such that the mounting holes and other components are aligned. In addition, the gantry system and conveyors must be sized and shaped to support the components, which can weigh several hundred to several thousand pounds. To this end, infrastructure costs for a new automotive plant generally exceed one billion dollars, representing a significant barrier to entry.

In addition to the required infrastructure, vehicles made using traditional manufacturing and assembly processes are difficult to service. Each different vehicle make and model has a different combination of components and assemblies. As a result, stocking all of the required parts for each vehicle can be difficult or impossible.

This application, on the other hand, refers to systems and methods that, while suitable for some traditional manufacturing, is suitable for use with modular vehicles. These vehicles can comprise relatively few assemblies, or “modules,” that are then mated during a final assembly step or process. In some examples, the vehicles may be assembled from two main types of modules, for example, a body module and a drive module (e.g., at least one drive module at one end of the body module). Indeed, in some examples, one type of drive module may be used with multiple types of body modules, further reducing complexity. Thus, the vehicle assembly plant can be very simple, compact, and inexpensive to construct and maintain. In addition, inventory management is simplified as the assembly plant need only maintain the few modules used to assemble the vehicle in inventory.

The modular construction of the vehicles described herein also greatly improves their serviceability. For instance, in the event of a failure or fault with a component of a module, the module can simply and quickly be removed and replaced with another module. For instance, if a fault occurs with a motor, battery, or other major system of a drive module, the drive module may simply be removed from the vehicle and replaced with another drive module. The replacement of a module may be performed by service personnel, an automated service robot (or robotic cart, as discussed below), or a combination thereof. As shown inFIGS. 1A and 1B, one solution to reducing capital investment is to use modular manufacturing techniques. As shown, a vehicle100can be constructed comprising a body102, a first drive unit104, and a second drive unit106, which can be assembled and disassembled horizontally instead of vertically. In this configuration, the vehicle100comprises the body102, which can act as a monocoque and passenger compartment, and the drive units104,106, which move and steer the vehicle, among other things. The drive units104,106can comprise, for example, one or more motors, internal combustion engines, fuel cells (or other power sources), differentials, controllers, steering systems, braking systems, HVAC, etc. The drive units104,106and the body102can be designed to mate very precisely such that fluids, electronics, HVAC and other functions between the subassemblies can be connected and disconnected using automated equipment and with little, or no, fluid loss.

When attaching the drive units104,106to the body102, it may be desirable, however, to provide a system that enables the use of automated machinery, such as automatic torque wrenches, robots, and/or robotic carts, as discussed below. It may also be desirable for the system to “hide” the fasteners, such that they are not visible during normal use. It may also be desirable to attach the drive units104,106to the body102without penetrating the passenger compartment. This can reduce water and air infiltration, reduce noise, reduce corrosion, and improve structural rigidity, among other things. It may also be desirable for the system to be able to insert, tighten, and torque the fasteners in a single step to improve efficiency, without the need for grommets, covers, or other accessories. It is to such a system that examples of the present disclosure are primarily directed.

To this end, a fastening system108can be used to horizontally couple the drive units104,106to the body102. As shown, the fastening system108can be attached to the drive units104,106and can be substantially hidden from view in the assembled state. As mentioned above, the fastening system108can include one or more driveshafts, disposed vertically below the vehicle100. The fastening system108can also include one or more spur gears, straight, spiral, or hypoid bevel gears, and related mechanisms to turn fasteners, with the fasteners disposed horizontally in the fastening system108. In some examples, the fastening system can include worm drives due to their ability to transmit higher torque loads when compared to other gear types. This can enable the fastening system108to horizontally attach the drive units104,106to the body (or vice-versa). The fastening system108can enable relatively conventional torquing devices, with vertical orientation, to be converted to improved modular, horizontal assembly procedures. In addition, the fastening system108and fasteners can be substantially hidden from view when assembled, obviating the need for additional steps or parts (e.g., seals or aesthetic covers).

As shown inFIG. 1B, in some examples, jack stands, blocks, or internal air or hydraulic jacks110can be used to support the body100when one or more of the drive units104,106is removed. In other words, the vehicle100is normally supported on the wheels112in the assembled state. Thus, in some examples, the jacks110can be used to support the body102when the drive units104,106are removed. In other examples, as discussed below with reference toFIGS. 6A-6C, a robotic cart600with a separable vehicle stand604can be used to support the body102.

As shown inFIG. 2A, examples of the present disclosure can comprise a fastening system108for attaching subassemblies during vehicle production. The fastening system108can enable a first subassembly202(e.g., the drive units104,106, discussed above) to be attached to a second subassembly204(e.g., the body102) with a plurality of fasteners206in a horizontal manner, such that the fasteners206are not visible in the installed position. As shown, in some examples, the fastening system108can be attached to the first subassembly202to enable the first subassembly202to be easily attached to the second subassembly204, or vice-versa.

As shown inFIG. 2B, the fastening system108and can also comprise a housing208and a drive system210. The housing208can comprise a casting or extrusion suitable to attach the fastening system108to one of the subassemblies202,204and can house the drive system210. When used on a vehicle100, for example, the housing208may not only house the drive system210, but may also act as part of the crash structure for the vehicle100. Thus, the housing208can act as a crumple zone and can include internal structure, such as ribs208a, for example, configured to deform in response to a predetermined crash force. This can enable the housing208to absorb crash energy, rather than transferring this energy to the vehicle100. The housing208can be replaced separately to minimize repair costs.

In other example, the housing208can instead (or in addition) support a separate crumple zone or crash structure on a surface facing an external portion of the vehicle100. Thus, additional crash structures can be bolted or bonded to an external surface of the housing208, for example. This may prevent damage to the drive system210and other components, further reducing repair costs.

In some examples, as shown inFIG. 2A, the fastening system108can be attached to a subframe212, such as a subframe for supporting the drive units104,106. Thus, the fastening system108can be used to attach the drive units104,106to the body102(depicted more generically as subassembly204). Though, as discussed above, the fastening system108is not so limited and can be used on other components of the vehicle100, other vehicles, or other machines or components.

Thus, turning one or more driveshafts214on the drive system210can rotate a series of mechanisms to rotate one or more fasteners206to detachably couple the first subassembly202to the second subassembly204. As shown, in some examples, the driveshaft(s)214can rotate a worm gear configured to change the direction of rotation from a first orientation (e.g., vertically below the vehicle100) to a second orientation (e.g., horizontally to the ground). The fastening system108can include a variety of drive interfaces configured to interface with a variety of torquing devices. The fastening system108can also include a variety of fastener drives to tighten and loosen multiple types and sizes of fasteners.

In some examples, to aid installation, the fasteners206can be captured between the drive system210and the housing208. In other words, the fastener206can pass through an aperture in the housing208that is sized to enable the shaft of the fastener to pass through, but not the head of the fastener206. As discussed below, the fastening system108can then be spring-loaded to promote extension of the fastener206of the fastening system (e.g., the driven gear308, discussed below) from the housing208. In this manner, the fasteners206can remain with the fastening system108when the subassembly202is removed, for example, to prevent loss or damage. In addition, upon reassembly of the components202,204, the fasteners are readily available for installation and are constantly driven into a respective receiving assembly. In some examples, such a spring assembly may promote alignment of multiple fasteners206driven by the drive system210. The spring assembly can also provide inward force on the fasteners206to ensure thread engagement upon reassembly. In some examples, as shown inFIG. 3B, below, the fastener206can also be tapered to provide additional alignment between the fastener206and the respective receiver in the subassembly102,104,106.

As shown from the rear inFIG. 3Aand from the front and exploded inFIG. 3B, the drive system210can comprise the first driveshaft214, second driveshaft302, worm shaft304, worm gear306, and driven gear308for each fastener206. As shown inFIG. 3A, the drive system210contains provisions for two fasteners206(e.g., two sets of gears304,306,308), but the fastening system108can be used with more or less fasteners206by adding or removing components.

As shown, the driveshaft(s)214,302can be engaged with the worm shaft(s)304to enable the fasteners206to be tightened from an angle that is substantially perpendicular to the fastener206. Thus, the driveshafts214,302can be located vertically beneath (or above) the vehicle100, with the fasteners206disposed in a substantially horizontal manner inside the fastening system108. In other words, in the orientation shown inFIGS. 3A and 3B, the worm shaft304can covert rotary motion about the y-axis, for example, into rotary motion about the x-axis.

Thus, while tightening tools (e.g., torque wrenches) can be inserted into the driveshafts302in the conventional manner e.g., vertically from below the vehicle100—the fasteners206can be tightened into the subassembly204horizontally. This enables the fasteners206to be located inside the housing208and, when tightened, inside the subassembly204such that they are substantially hidden from view. In addition, the use of a simple seal322(e.g., a lip seal, as shown inFIG. 3B) between the driveshaft(s)214,302and the housing208, for example, can enable the fasteners206to be substantially sealed from the elements. Thus, the fasteners206are hidden and protected without the need for additional steps or components during assembly, increasing productivity and reducing costs.

As shown inFIGS. 3A and 3B, when two fasteners206are employed, the drive system210can comprise one driveshaft214(FIG. 3A) or two driveshafts214,302(FIG. 3B), two worm shafts304, two worm gears306, and two driven gears308. In some examples, as shown inFIG. 3A, the drive system210can include a single driveshaft214coupled to both worm shafts304to enable both fasteners206to be tightened at the same time and with the same tool. This may be useful when fastener torque is less critical, for example, or when the conditions can be controlled such that each fastener206receives substantially the same fastening torque.

In other examples, as shown inFIG. 3B, the drive system210can include separate driveshafts214,302, one for each worm shaft304. Thus, in this configuration, the outer driveshaft214can turn the lower worm shaft304a, while the inner driveshaft302can turn the upper worm shaft304b. In this manner, each fastener206can be independently tightened and torqued. In some examples, the driveshafts214,302can be concentric such that an inner driveshaft302rotates inside an outer driveshaft214. In this configuration, the driveshafts214,302can also comprise separate drive interfaces310a,310bto enable each driveshaft214,302to be driven independently.

As shown, in some examples, rather than using a single worm shaft304that spans a significant portion of the driveshaft's length, the drive system210can comprise a single, short worm shaft304for each fastener206. In some examples, the drive system210can also include a drive housing312for each worm shaft304. The drive housing312can be designed to not only house the drive system210, but to act as a structural and/or crash member for the drive module104or vehicle100.

The drive housing312, in turn, can include one or more bushings or bearings314to reduce the flex of driveshaft(s)302proximate the worm shaft304. Thus, the drive housing312can include an upper bearing314a, disposed above the worm shaft304, for example, and a lower bearing314bdisposed below the worm shaft304. Of course, depending on the size of the drive system210, more or less bearings314can be used.

The housing208can be shaped and sized to house drive system210, which includes the worm shaft304and the worm gear306. As shown, the housing208can comprise a substantially cylindrical portion to house the worm shaft304and a substantially circular portion to house the worm gear306. The housing208may also include seals, grease fittings, and other components suitable to maintain and service the components304,306,308of the drive system210.

The combination of the bearings314, drive housing312, and worm shafts304can substantially eliminate flexing of the worm shafts304with respect to the worm gears306. This reduces friction and wear on both gears304,306. This also enables more accurate torque measurement when torquing the fasteners206during assembly. This configuration also enables the driveshafts302(as opposed to the worm shafts304) to be somewhat flexible since they are not required to locate the worm shafts304. In this manner, slight misalignments between the driveshafts302and any drive tools (e.g., a robotic torque wrench) can be absorbed by the driveshafts302, further reducing wear on the gears304,306. Thus, while a slight misalignment between a torque wrench and the drive system210may cause one, or both driveshafts214,302to bow slightly, for example, the alignment between the worm shafts304and the worm gears306is maintained.

As shown, the worm gear306can be rotated by the worm shaft304, while the driven gear308can be turned by the worm gear306. Thus, the worm gear306can comprise a complementary tooth pattern to the worm shaft304to turn the direction of rotation of the driveshafts214,302through approximately 90 degrees. The worm gear306can also comprise internal teeth suitable to engage with the external teeth of the driven gear308. As briefly noted above, such a worm gear combination may enable high torques to be transferred, though other suitably sized gear configurations could also be used.

Thus, the driven gear308is turned by the worm gear306and, in turn, turns the fastener206. To this end, the driven gear308can include an interface316to rotate, tighten, and torque the fasteners206. As shown, in some examples, the interface316can simply comprise and appropriately sized hole in the driven gear308(e.g., a hex, 8-point, or 12-point “socket”). In other examples, as discussed below, the driven gear308can include an insert, or adapter, to enable a single type or size of driven gear308to be adapted to multiple types and sizes of fasteners206. In still other examples, to reduce complexity, the worm gear306can drive the fastener206directly obviating the need for the driven gear308.

In some examples, to facilitate maintenance and repair, the drive system210can also comprise a removable cover318and a spring320. As shown, in some examples, the cover318can be removable to provide access to the worm gear306, driven gear308, and other fastening system108components. This can enable the components304,306,308to be inspected, cleaned, lubricated, and/or replaced without completely disassembling the drive system210(or the fastening system108or removing it from the vehicle100). In addition, in the event of a failure of the drive system210such as, for example, a broken gear304,306,308or a jammed or cross-threaded fastener206, the cover318and spring320can be removed from the rear of the fastening system108. Once removed, the worm gear306and/or driven gear308, for example, can also be extracted through an appropriately sized aperture312ain the drive housing312to enable the drive system210to be serviced in situ.

Significantly, in some examples, the driven gear308can be removed through the aperture312ato enable a manual socket to be inserted through the drive housing312and the worm gear306. Thus, a manual ratchet or wrench can be used to extract the fastener206, for example, for replacement and/or drive the fastener206directly into or out of the respective receiving region. This may be because the fastener206is damaged, cross-threaded, corroded, or has simply reached the end of its service life (i.e., it has been retorqued a predetermined number of times. Thus, the fastener206can be removed and replaced without removing the fastening system108from the vehicle100and without disturbing the setup (e.g., backlash) between the worm shaft304and worm gear306. In addition, the drive unit104,106can be removed from the vehicle100, for example, despite a mechanical failure.

As shown inFIG. 4A, in some examples, the ends of the driveshafts214,302can be substantially coplanar. In this configuration, to enable each driveshaft214,302to be turned separately, the inner driveshaft302can comprise an internal drive interface402such as, for example, an internal hex (e.g., Allen®), internal Torx®, square drive, or another type of internal drive interface402, while the outer driveshaft214can comprise an external drive interface404, such as an external hex, external 12-point, or another external drive interface404. This may enable a dual (concentric) torque wrench, for example, to tighten both fasteners206separately, but at the same time. In addition, this configuration can shorten the overall length of the driveshafts214,302and thus, the drive system210. In other words, the internal drive interface402enables the inner driveshaft302to be turned even though the internal driveshaft302and external driveshaft214terminate at the same point (i.e., they are not the same length, but their ends are flush), reducing the overall length required for the driveshafts214,302.

As shown inFIG. 4B, in other examples, both driveshafts302can comprise external drive interfaces404, with the inner driveshaft302being longer than the outer driveshaft214to enable access to both drive interfaces404. In this configuration, the first drive interface404afor the inner driveshaft302can comprise a smaller, external hex or 12-point, for example, which can be turned with a smaller, standard depth socket. The second drive interface404bfor the outer driveshaft214, on the other hand, can comprise a larger, external hex or 12-point, for example, which can be driven with a larger, deep socket. Regardless, the separate driveshafts214,302can enable each fastener206to be tightened and torqued independently, if desired. In some examples, the inner driveshaft302can also include an internal drive interface402to provide redundancy and/or improved access, as necessary.

As shown inFIG. 4C, in other examples, the inner driveshaft302and the outer driveshaft214can have the same size external interface404b,406. In this configuration, the first drive interface406for the inner driveshaft302can comprise the same size external hex or 12-point, for example, which can be turned with the same socket or driver as the outer drive shaft214. Thus, both the first drive interface406and the second drive interface can be driven with the same, deep socket. This can be used when there is an acceptable range of torques for each fastener406(e.g., less precision is required) or by adjusting the length or thread pitch of the fasteners406, for example, to achieve the desired torques.

As mentioned above, in some examples, the interface316molded directly into the driven gear308can turn the fasteners directly. In other examples, the interface316can be molded directly into the worm gear306, obviating the need for the driven gear308(though this may affect serviceability). In still other examples, as shown inFIGS. 5A-5C, the driven gear308can include a fastener insert502, disposed inside the interface316, to adapt the driven gear308to a variety of fastener sizes and/or types. Thus, the interface316of the driven gear308can comprise, for example, a hex (shown), 12-point, spline, or other drive to couple with the fastener insert502. The fastener insert502, in turn, can comprise a fastener drive504,508configured to rotate a fastener and can include a complementary external surface506e.g., sized and shaped to fit inside the interface316.

Each fastener insert502can comprise a fastener drive504sized and shaped to rotate a specific size and type of fastener. Thus, the fastener inserts502can comprise, for example, external fastener drives504a,504b(FIGS. 5A and 5B, respectively) for external fasteners like hex bolts. The fastener inserts502can also comprise internal fastener drives508(FIG. 5C) for internal fasteners like Allen® or internal Torx® bolts.

As shown, a large fastener insert502acan include a large, external fastener drive504afor turning large, external fasteners (e.g., large hex bolts). Similarly, a small external fastener insert502bcan include a small, external fastener drive504bto turn smaller external fasteners (e.g., small hex bolts). Thus, while the fastener inserts502a,502bare externally the same size and configured to fit inside the driven gear308, the fastener drives504can be different sizes for different sized fasteners.

In addition, as shown inFIG. 5C, the fastener insert502ccan also comprise an internal fastener drive508to drive internal fasteners in this case an Allen® bolt. Thus, the internal fastener drive508can be sized and shaped to fit different sized (e.g., ¼″, ½″, 5 mm, 6 mm, 7 mm, etc.) and different style (e.g., Torx®, Allen®, splined, square drive, star, flat head, Phillips, etc.) internal fasteners. Thus, by simply changing out the fastener inserts502, the fastening system108can be adapted to different sizes and types of fasteners.

This modular configuration can also enable the driven gear308and the fastener insert502to be made of different materials to, for example, reduce fastener damage, improve wear characteristics, reduce friction, and/or reduce noise. Thus, the fastener insert502can comprise nylon, for example, or another softer material to substantially prevent any coatings (e.g., zinc chromate) on the fastener from being removed during tightening and removal procedures. Thus, the fastener insert502can comprise a polymer, for example, while the driven gear308can comprise a metal. The fastener insert502can also comprise a hard material to reduce wear on the fastener insert502, while enabling a softer material to be used for the driven gear308to reduce wear on the drive gear306. Other combinations are also possible.

This configuration can provide additional modularity. In other words, the driven gear308can be a standard size with a standard sized interface316. The fastener inserts502, in turn, can each comprise a standard external surface506and a different sized fastener drive504, or “socket,” for a specific size and/or style of fastener. So, for example, the large fastener insert502acan comprise a 12 mm fastener drive504aand the small fastener insert502bcan comprise an 8 mm fastener drive504b. Of course, these sizes a purely exemplary and other sizes are possible. Indeed, as mentioned above, the fastener inserts502can also comprise either external drives (hex, 12-point, etc.) or internal drives (e.g., Allen®, Torx®, etc.), as desired.

In this manner, the fastening system108can be substantially standardized and can be used on vehicles100with multiple sizes or styles of fasteners206or on multiple different types of vehicles serviced in the same facility. In some examples, the fastening system108can include multiple sizes suitable to service a range of fastener sizes. In other words, the fastening system108can include, for example, a small, medium, and large size, with each fastening system108suitable to a range of fastener sizes (e.g., 4-8 mm, 10-12 mm, and 14-16 mm, respectively). Thus, each fastening system108includes appropriately sized (and torque rated) components214,302,304,306,308and a plurality of fastener inserts502sized and shaped for the range of covered fasteners206.

As shown inFIGS. 6A-6C, the fastening system108can be used in conjunction with a robotic cart600. Thus, the robotic cart600can be used, for example, to remove the subassemblies104,106from the body102for maintenance and repair, among other things. The robotic cart600can comprise, for example, a main body602and a vehicle stand604. The main body602can comprise, for example, one or more drive systems606, each comprising one or more motors/transmissions, and a plurality of wheels, rollers, casters, or another suitable component.

The drive systems606can comprise any type of motor suitable to move the cart600and/or the subassemblies104,106throughout a service facility, for example, or an assembly plant. In some examples, the drive systems606can comprise for example, direct drive electric motors (i.e., without using transmissions), electric motors acting through transmissions, servo motors, or another type of electric motor. In other examples, the drive systems606can comprise pneumatic or hydraulic motors power by a pump that is itself driven by a central electric motor, internal combustion engine, fuel cell, etc.

Regardless, the main body602can comprise one or more docking pins608and one or more torquing devices610. The torquing devices610can comprise any of a variety of automated/robotic torque-controlled screwdrivers and nutdrivers, such as those commonly used on vehicle assembly lines. The docking pins608can comprise pins, cups, latches, or other suitable interface to enable the cart600to securely lift and move the drive units104,106. Thus, in some examples, the docking pins608can simply comprise pins, for example, that are sized and shaped to be inserted into complementary holes in the drive units104,106. In other examples, the docking pins608can comprise cups or holes, for example, into which complementary hemispheres or pins in the drive units104,106can be received. The docking pins608and their respective complementary receiving portions on the drive units104,106may be sized and shaped to promote alignment. Thus, the docking pins608can serve to locate, align, and/or provide fixturing between, for example, the cart600and the vehicle100.

The main body602can also comprise one or more torquing devices610configured to interface with the fastening system108. Thus, the torquing device610can comprise, for example, a mechanical or electronic torque wrench configured to tighten and loosen the fasteners206to enable the drive units104,106to be installed and removed from the vehicle100. The torquing devices610can comprise automatic electric or hydraulic torque wrenches, for example, configured to tighten the fasteners206to one or more preset tightening torques or torque-to-yield (TTY) settings. The torquing devices610can also be used to loosen the fasteners206to enable the drive units104,106to be removed.

As mentioned above, in some examples, the fastening system108can comprise multiple driveshafts302to enable the fasteners206to be tightened, loosened, and torqued independently. In this configuration, the torquing device610can comprise complementary torque wrenches. So, for example, in the case of concentric driveshafts214,302, discussed above, the torquing device610can include a first torque wrench for the inner driveshaft302and a second torque wrench for the outer driveshaft214, with the appropriate tool on each torquing device610for the respective driveshaft302. Of course, in some examples, the torquing device610can include a single torque wrench with multiple heads, concentric heads, or other devices, for this purpose.

In some examples, the torquing devices610can be moved in one or more axis to enable the torquing devices610to be aligned with the driveshafts214,302. The torquing devices610can be moved back and forth or side-to-side, for example, to center the torquing devices610on the driveshafts214,302. The torquing devices610can also be moved vertically from a lowered position (FIG. 6A) to a raised position (FIG. 6C) to enable the cart600to engage with the driveshafts214,302.

In some examples, the cart600can also include an upper stanchion612including one or more additional docking pins608. As before, these docking pins608can be, for example, pins, cups, latches, or other devices suitable to engage with the drive units104,106. The upper stanchion612can support an upper portion of the drive units104,106to substantially prevent the drive units104,106from rolling, tipping, or otherwise falling, off the cart600. This can provide additional security when the cart600removes, installs, and transports the drive units104,106during operation.

In some examples, such as for vehicles100with moveable suspensions, the upper stanchions612can be fixed. In this configuration, the cart600can be positioned under the vehicle100with the docking pins608aligned with the pickup points on the vehicle100. The vehicle100can then alter its suspension to first provide clearance for the cart600and then lower onto the cart600.

In other examples, such as for vehicles100with fixed suspensions, the upper stanchions612can be moveable. The upper stanchions612can be mounted on actuators612asuch as, for example, pneumatic or hydraulic rams, linear actuators, or screw drives to enable the cart600to lift the vehicle100. In this configuration, the cart600can be positioned under the vehicle100with the docking pins608aligned with the pickup points on the vehicle100and the upper stanchions612can be moved from a lowered position (FIG. 6C) to a raised position (FIG. 6A), as shown by Arrow A, to raise the vehicle100off the ground.

In some examples, the upper stanchions612can also include additional torquing devices610. Thus, raising the upper stanchions612can enable the torquing devices610to engage with fasteners206on the drive module104,106or other subassemblies. Of course, while shown vertically oriented, in some examples, the torquing devices610can be disposed horizontally on the ends of the upper stanchions612to tighten horizontal fasteners206.

The cart600can also include the vehicle stand604. As shown inFIG. 6C, the vehicle stand604can be detachable from the main body602, as shown by Arrow B, and can support the vehicle100when one, or both, of the drive units104,106is removed. To this end, the vehicle stand604can include one or more docking pins608and a foot614. As before, the docking pins608can be, for example, pins, cups, latches, or other devices, but in this case, can be suitable to engage with complementary pickup points on the body102(i.e., as opposed to the drive units104,106). In other words, because the body102is normally supported by the wheels of the vehicle100, when a drive unit104,106is removed, it may be necessary to support the body102until a drive unit104,106is reinstalled.

In some examples, such as when the cart600is used on vehicles100with active suspensions, the foot614can be a simple pin or bar. Thus, the cart600can move under the vehicle100, the vehicle100can alter its suspension (lowering the vehicle100onto the cart600), and the vehicle100can simply rest on the vehicle stand604. In this configuration, as the cart600removes the drive unit104,106from the vehicle100, the vehicle stand604can detach from the cart600to support the vehicle100. When the cart600returns with the drive unit104,106(or a replacement drive unit104,106), the drive unit104,106can be reinstalled and the suspension altered to raise the vehicle100off of the cart600. The vehicle stand604can then be reattached to the cart600for removal to another location. This process is described in more detail below with respect toFIGS. 7A and 7B.

In other examples, such as on vehicles100with conventional (non-active) suspension systems, the foot614can comprise, for example, a hydraulic, pneumatic, or electric jack to enable the vehicle100to be lifted to remove the drive units104,106. Thus, as shown inFIG. 6C, for example, the foot614can move vertically, as shown by Arrow C, up and down from a retracted position (FIG. 6A) to an extended position (FIG. 6C) to support the body102. In some examples, the vehicle stand604and foot614can be substantially self-contained. In other words, the vehicle stand604can comprise an internal battery and the foot614can comprise an electric jack to raise the vehicle. In this manner, fewer, or no, connections are needed between the main body602and the vehicle stand604. In this configuration, the main body602and vehicle stand604may nonetheless be wirelessly connected (e.g., using Bluetooth® or Wi-Fi) to enable signaling between various components.

In other examples, the cart600can comprise, for example, electrical, pneumatic, and/or hydraulic (e.g., “dry-break”) connections between the cart600and the vehicle stand604to enable the cart600to power the vehicle stand604, yet enable the vehicle stand604and cart600to separate. Thus, the cart600can position itself under the vehicle100, the foot614can extend, and the cart600can disconnect from the vehicle stand604. The cart600can then remove the drive unit104,106from the vehicle100for service, repair, or replacement, leaving the body102resting on the vehicle stand604(and foot614).

In still other examples, the cart600can include a moveable suspension. In this configuration, the drive system606, for example, can be mounted on an actuator to enable the cart600to be moved up and down. The drive system606can be mounted on airbags, for example, or linear actuators to move between a lowered position and a raised position. In this manner, the cart600and the foot614can both lift the vehicle100to a predetermined height to enable the drive unit(s)104,106to be removed.

The cart600can also include a propulsion control system616and a plurality of sensors618to enable the cart600to properly locate the vehicle100, position itself under the vehicle100, locate the drive interfaces310, and locate any pickup points on the vehicle100, etc. The sensors618can include, for example, one or more image sensors618a, radio distance and ranging (RADAR) sensors618b, and/or laser distance and ranging (LIDAR) sensors618cmounted on the cart600. The sensors618can also comprise a global positioning system (GPS), inertial measurement unit (IMU), accelerometers, gyrometers, and other sensors. The sensors618can be arranged in a predetermined pattern, for example, in order to provide a desired area of coverage for the area proximate, and under, the vehicle100. In some examples, as shown, the sensors618can be disposed in a pattern that enables approximately 360-degree coverage around the cart600. This can enable the cart600to detect objects regardless of which direction the cart600is traveling (e.g., to, or from, the vehicle100). This can also enable the cart600to detect objects approaching from the sides of the cart600(e.g., another cart600or a worker in a service facility). Other patterns and arrangements of the sensors618are contemplated.

The image sensors618amay be any known types of digital image sensors, digital or analog cameras, and/or digital or analog video cameras. The image sensors618amay be high dynamic range (HDR) cameras, for example, to provide improved accuracy of the images. In some examples, the image sensors618amay include one or more of light-sensitive cameras, range sensors, tomography devices, RADAR, and/or ultra-sonic cameras. Other suitable types of imagers are contemplated. The imager sensors618amay be selected to provide two-dimensional (2-D) image data, two and a half-dimensional (2.5d, or depth maps), and/or three-dimensional (3D) image data, image sequences, gray scale (or intensity) image data, and/or color image data. In some examples, the imager sensors618amay be selected to provide depth data, absorption data, and/or reflectance data.

As shown, the example sensors618may be mounted to a portion of the cart600that provides a line-of-site view of a portion of the area around the cart600, with at least a portion of the sensors618pointed in, or moveable to, the direction of travel and at least a portion of the sensors618pointed in, or moveable to, the upward-looking position. This can enable the cart600to safely travel through a maintenance facility, for example, and to properly position itself underneath the vehicle100for maintenance. The sensors618may be located separately from one another and on different parts of the cart600, as shown, or incorporated into one or more sensor arrays.

The sensors618can enable the cart600to position itself properly underneath the vehicle100, among other things. To this end, the vehicle100and/or surrounding environment can include fiducials configured to be identified by the sensors618. In some examples, the pickup points on the vehicle100and/or disposed about the environment of the vehicle, can include bar codes, artificial reality tags, QR codes, retroreflectors, etc., for example. In some examples, sensor fusion (e.g. using SLAM, Kalman filters, bundle adjustment, etc.) to predict a pose of the cart600can be used to accurately localize the cart600and plan a trajectory to mate with the vehicle100. In other examples, the image sensors618acan be used to identify the pickup points and other features of the vehicle100for this purpose. The process of localizing the cart600is described in more detail below with reference toFIGS. 7A, 7B, and 8.

In some examples, rather than being robotic, the cart600can be controlled by a worker using a remote control or a handle620on the cart. The handle620can act as a joystick, for example, to enable the worker to maneuver the cart600into place under the vehicle100. In some examples, the sensors618can include lights to indicate which way the cart600needs to be moved to align with the vehicle100or a fiducial. In other examples, the cart600can include an LCD screen, or other display, to provide directions to the worker.

The cart600can also comprise a torque control system622. The torque control system622can provide control for the positioning and operation of the torquing devices610. The torque control system622can receive various sensor inputs to enable the torquing devices610to be centered on the driveshafts214,302and then raised into engagement. The torque control system622can also control the torque applied through the drive system208by the torquing devices610. Thus, the torque control system622can receive inputs from torque sensors, position encoders, and other sensors to provide the desired torque on the fasteners206.

The torque control system622can also ensure the fasteners206are properly removed during disassembly. This can be achieved by detecting a torque spike, for example, to “break the fastener206loose” followed by a predetermined number of turns on the fastener206. Thus, the torque control system622may turn the fastener406eight times (or whatever number is required) to remove the fastener406, plus another two turns to ensure the fastener406is completely removed.

As shown inFIG. 6C, in some examples, the vehicle stand604can be detachably coupled to the main body602using one or more latches622. In some examples, the latches622can comprise, for example, mechanical latches. Thus, the latches622can comprise, for example, screw drives, cam locks, retractable hooks, or other mechanism suitable to mechanically couple the vehicle stand604to the main body602. In other examples, the latches622can comprise electronic latches such as, for example, electromagnets, linear actuators, screw drives, etc. In either case, the latches622can be remotely activated to enable the cart600, the vehicle100, or a central control to provide a signal to cause the vehicle stand604to couple to, or decouple from, the vehicle100.

In some examples, one or more fiducials624can be placed on the ground in the service area. For automated vehicles, for example, the vehicle100can positioning itself over the fiducial624for service. The cart600can then position itself using the fiducial624. In this manner, the cart600and the vehicle100can be properly located using the same frame of reference. The cart600can position itself (or a sensor618) over the fiducial624, for example, and then engage with the vehicle100.

In some examples, the vehicle stand604can also include a plurality of casters626, rollers, wheels, or other device to enable the vehicle100to be moved when one, or both, of the drive modules104,106is removed. The drive modules104,106may be removed to recharge or replace batteries, for example, while the body102may be wheeled into the body shop to repair dents or dings obtained during use. The casters626can enable multiple repairs to be provided at the same time, among other things.

In some examples, the vehicle stand604can also comprise one or more lifting points628. The lifting points628can enable the body102to be safely lifted with a crane or other device to enable the body to be moved, lifted, and/or rotated to facilitate service. In some examples, the vehicle stand604can include two lifting points sized and shaped to accept, for example, the tines of a forklift for easy maneuvering.

As shown inFIGS. 7A and 7B, examples of the present disclosure can also comprise a method700of using the fastening system108in conjunction with the robotic cart600. The cart600can be used to remove and replace drive units104,106for maintenance operations, battery swaps, and reconfigurations, among other things. Thus, and in general, the cart600can approach the vehicle100, align with the vehicle100and drive unit104,106, remove or decouple the fasteners206, and then remove the drive unit104,106from the vehicle100. For modular vehicles100, the cart600can then replace the same drive unit104,106(e.g., after service or repair), for example, or replace the drive unit104,106with a new drive unit104,106that has already been recharged, serviced, or repaired.

At702, therefore, the cart600can approach the vehicle100and position itself in the appropriate location proximate a first end750of the vehicle100. So, for example, the cart600can approach the vehicle100using one or more of the sensors618to determine its position relative to the vehicle100. Once the cart600is with a predetermined distance from the vehicle100(e.g., 3 or 5 feet), the cart600can reduce its speed for final positioning.

In some examples, the cart600can, at least partially, be manually positioned. In other words, rather than being entirely robotic, the cart600can be manually pushed into place by a worker, for example, or controlled by a worker with a remote control. In this configuration, the worker can guide the cart600into and approximate location beneath the vehicle100pending final positioning.

At704, the cart600can begin final positioning under the vehicle100. In some examples, this can include switching from forward-looking sensors618to upward- or downward-looking sensors618. In other examples, the cart600can locate fiducials, holes, pins, or other locators on the vehicle100or on the ground beneath the vehicle100using the one or more of the sensors618. Thus, the cart600can move to align the docking pins608with the appropriate pick-up points on the vehicle100. The process of localizing the cart600is described in more detail below with reference toFIG. 8.

In other examples, the cart600can be manually maneuvered (i.e., by hand or with a remote control) into place by a worker. Thus, the cart600can include lights or a digital display, for example, to indicate which direction the cart600needs to be moved to be properly aligned with the vehicle100based on the sensor data. So, for example, the cart600can include four lights (right, left, forward, and backward) or arrows on an LCD screen, for example, to enable the worker to precisely located the cart600underneath the vehicle100.

In some examples, in the operation704, the cart600can also establish communications between the cart600and the vehicle100. In some examples, the cart600can communicate with the vehicle100via a wireless connection (e.g., using Bluetooth® or Wi-Fi). In other examples, the cart600can communication with the vehicle100using a wired connection. Thus, as discussed above, a docking pin608on the cart600, for example, can include a plug suitable to interface with a complementary plug on the vehicle100.

In still other examples, the vehicle100and the cart600may be in communication with a central control (e.g., a central computer or cloud service) associated with the maintenance facility. Thus, each component100,600can be in communication with the central control and providing status messages as the method700progresses. The central control can, in turn, provide commands to the components100,600to perform various actions, as necessary.

Regardless of the method of communication, in some examples, the vehicle100can open hatches752, covers, or other access panels as necessary to enable the cart600to access one or more pickup points or fasteners206on the vehicle100and/or drive unit104,106. Thus, as shown, the vehicle100may open a rear hatch752, as shown by Arrow D, to enable the upper stanchions612to be positioned below pickup points on the top of the drive unit104,106.

At706, for vehicles100with active suspensions, airbags, or otherwise moveable suspension components, the vehicle100can raise or lower the front suspension754, as shown by Arrow E. In some examples, the vehicle100may perform this act in response to the cart600attaining a predetermined orientation, or pose, relative to the vehicle100(i.e., the vehicle100sensing the cart600is in the proper position). In other examples, the vehicle100may perform this act in response to a signal from the cart600or the central control. The vehicle100may first raise the suspension, for example, to provide additional clearance for the cart600and then lower the suspension to “squat” onto the cart600.

As shown, raising the suspension on the vehicle100effectively lowers the vehicle100onto the cart600. As mentioned above, in this configuration, the foot614can be substantially passive and can simply support the weight of the vehicle100when the drive unit104,106is removed. In this configuration, therefore, as the body102lowers onto the foot614, the foot614is trapped between the body102and the ground756and supports the vehicle100. In some examples, the foot614can include a spring or shock, for example, that compresses as the body102is lowered to provide some cushion to the body102.

In some examples, to provide additional clearance underneath the vehicle100, the front suspension may initially lower (raise the vehicle100) and then raise (lower the vehicle100). So, when the vehicle100is placed into service mode, for example, the vehicle100may automatically raise slightly (e.g., 1-6″) to increase clearance under the vehicle100. In response to subsequently receiving a signal from the cart600or a central control, for example, the vehicle100can then lower onto the cart600raising the wheels off the ground.

For vehicles100with conventional, or passive, suspensions, the cart600and/or the foot614can include a jack to raise the first end750of the vehicle100slightly. This can enable the wheels758to be raised slightly off the ground756to enable the drive unit104,106to be removed. In this configuration, the foot614can also support the body102as the drive unit104,106is removed. As mentioned above, however, in this configuration, the foot614and/or the cart600can include a jack that uses hydraulic power, electric power, pneumatic power, or a combination thereof to lift the drive unit104,106and/or body102to facilitate the removal of the drive unit104,106from the body.

At708, regardless of the lift mechanism, the torquing devices610on the cart600can engage with the drive interface(s)310on the fastening system108. In some examples, the cart600the torquing device(s)610can already be properly located when the cart600located itself beneath the vehicle100. In other words, the act of the cart600engaging with the vehicle100e.g., the vehicle100lowering on to the cart600or the cart600raising to meet the vehicle100engages the torquing devices610with the drive interface(s)310at the same time.

In other examples, the cart600can simply raise the torquing device(s)610(on the cart600and/or the upper stanchions612) into place, as shown by Arrow F, with the torquing device(s)610having been previously located in the x- and y-axes by virtue of the cart600locating itself beneath the vehicle100. In still other examples, the torquing device(s)610may include additional sensors to position and/or fine tune the location of the torquing device(s)610with respect to the drive interface(s)310. Thus, the torquing device(s)610may move slightly fore and aft, left and right, and/or vertically to engage the drive interface(s)310.

Once engaged, the torquing devices610can loosen the fasteners206, which connect the drive unit104,106to the body102. To this end, the torquing device(s)610can rotate the driveshaft(s)214,302(via the drive interface(s)310) as necessary to remove the fasteners206(i.e., ultimately via the interface316or fastener inserts502). Thus, the torquing device(s)610can rotate the fastener(s)206clockwise or counter-clockwise (for reverse thread) to remove the fastener(s)206from the body102. As discussed above, in some examples, the fastener(s)206can be captured inside the fastening system108e.g., between the driven gear308and then housing208and can remain with the drive unit104,106in mechanical engagement with the interface316.

At710, the cart600can lower the foot614(if applicable) and disengage from the vehicle stand604. As discussed above, in some examples, the cart600can lower the foot614, as shown by Arrow G, to support the body102when the drive unit104is removed. In addition, the cart600can include fasteners, latches622, or other mechanisms to enable the cart600and the vehicle stand604to be detachable. This may be in response to a signal from the cart600, vehicle100, or central control to the vehicle stand604. This can enable the vehicle stand604to separate from the main body602of the cart600. At this point, the cart600can support the drive unit104while the foot614can support the body102of the vehicle100.

At this stage, having separated from the vehicle stand604, the cart600may slightly lower for clearance and can begin to move slowly backwards, as shown by Arrow H, to remove the drive unit104,106from the body102. In some examples, the cart600may continue to scan the body102with the sensors618to avoid collisions between the cart600and/or drive unit104,106and the body102. The cart600may also proceed at a first predetermined speed (e.g., less than 1 MPH) until the cart600and/or the drive unit104,106has moved a first predetermined distance from the body102.

At712, once the cart600and/or the drive unit104,106have reached the first predetermined distance from the body102, the cart600may raise slightly and accelerate to a second predetermined speed (e.g., 1, 2, 3, 5, etc. MPH) to move the drive unit104,106throughout the service facility. As discussed above, in some examples, the drive unit104,106can be exchanged for a drive unit104,106that had been, for example, repaired or recharged. In other examples, the drive unit104,106can be removed to enable it to be repaired or to provide access to the body102, or other components, for service and repair, as necessary.

For example, while shown removing the drive unit104,106from the body102, the cart600can also be used to reinstall the drive unit104,106to the body102by essentially reversing the order of the steps. In addition, the cart600can also be used to install and remove different subassemblies and assemblies from different types of machines and mechanisms. Thus, the description of the method700above is intended to be illustrative, as opposed to limiting.

FIG. 8is a component level schematic view an example of an electronic device. For ease of explanation, the electronic device is described in terms of the functions of the propulsion control system616. One of skill in the art will recognize, however, that the electronic device can be used for many other functions in the vehicle100or cart600, for example, with minor modification. Indeed, a similar electronic device can comprise a component of the torquing devices610or other electronic components for use with the systems108,600and method700described herein. In some examples, the propulsion control system616can comprise a dedicated electronic device, such as a dedicated microcontroller. Other components of the cart600, however, can comprise an electronic device with multiple functions such as, for example, a cell phone, smart phone, laptop, tablet, or another electronic device that comprise a number of components to gather data, communicate, and maneuver, among other things.

The propulsion control system616for the cart600can comprise memory802configured to include computer-executable instructions including at least an operating system (OS)804for receiving data and controlling the drive system(s)606, sensors618, and other components. The OS804can also make calculations (e.g., calculate the current distance between the vehicle100and the cart600), communicate with other components in the vehicle100(e.g., to open the hatch752), the torquing devices610, and other components. The memory802can also include a localization module806, a drive unit data808, a torque data810, and a vehicle support data812.

The localization module806can receive sensor data from the sensors618on the cart600to calculate precise trajectories at a given frequency to maneuver the cart600safely through an environment (e.g., a maintenance facility or assembly plant), as described herein. Such a trajectory may correspond to a series of poses (i.e. position and orientation), linear and angular velocities, as well as linear and angular accelerations for the cart600. In turn, such trajectories may be translated to control steering angles and torque and/or braking applied by the drive system(s)606on the cart600.

The localization module806can receive current sensor data from the sensors618. As mentioned above, this can include, for example, a variety of data from imagers (e.g. RGB cameras, RGB-D cameras, greyscale cameras, etc.), LIDAR, RADAR, GPS, and other sensors to localize the cart600(i.e. provide a position and/or orientation) relative to a map and relative to the vehicle100. This can also include inputs from, for example, wheel encoders, gyroscopes, magnetometers, accelerometers and/or IMUs to provide linear acceleration and angular velocities. Deviations from an expected trajectory may then be measured from a measured position and/or orientation when localizing to position the cart600near to, and then under, the vehicle100being serviced.

In some examples, the cart600and/or the vehicle100can be positioned using one or more fiducials on the floor or walls of the service facility. In this configuration, the vehicle100can moved into the service facility and position itself relative to the fiducials (e.g., with a particular fiducial directly underneath a predetermined sensor on the vehicle100). The cart600can then use the same fiducial(s) to precisely locate itself underneath the vehicle100in a similar manner. This positioning may also be supplemented with additional sensors (e.g., high-resolution video cameras) to confirm the positioning of the cart600.

The memory802can also include the drive unit data808. The drive unit data808can include location and tightening data for the various drive units104,106being serviced. The drive unit data808can comprise, for example, the location of the drive interface(s)310, including, for example, their location relative to the body102or drive units104,106, the height from ground, and other relevant information. The drive unit data808can also include the type of drives used on the drive interface(s)310such as, for example, internal or external drive interfaces, size, type (e.g., hex or Torx®), etc. In facilities that service multiple types of vehicles100or drive units104,106, the drive unit data808can also include this data about each type of drive unit104,106, vehicle100, version, build number, and other variations.

The memory802can also include the torque data810. The torque data810can include data about torque specifications and procedures to control the torquing devices610. Thus, the torque data810can include torque values for each type or size of fastener206, each drive unit104,106, each vehicle100, etc. Thus, some drive units104,106can include multiple fastener sizes, for example, each requiring a separate torque value. Other drive units104,106may require a torquing sequence e.g., torque to 15 ft. lbs., then 45 ft. lbs., and then 75 ft. lbs. Similarly, some drive units104,106may have torque-to-yield (TTY) fasteners206e.g., torque to 45 ft. lbs. and then turn an addition 90 degrees or other torquing procedures. In addition, many fasteners206can only be torqued once (e.g., TTY fasteners), while others can be only torqued a finite number of times, before they must be replaced. Thus, the torquing procedures, torque values, number of times the fastener has been torqued, and related data can be stored and updated in the torque data810.

The memory802can also comprise a vehicle support data812to control the foot614and/or latches622on the vehicle stand604. Depending on the type of latches622used, for example, the vehicle support data812can comprise a driver for a linear actuator, electromagnet, servo motor, or other suitable actuator. The vehicle support data812can also include data regarding the weight of the body102, for example, and the location of various significant points on the body102for one or more vehicles100. The vehicle support data812can include, for example, the location of various pickup points on the vehicle100to enable the cart600to align itself and the docking pins608, among other things. The vehicle support data812can also include the location of jacking points on the body102to enable the vehicle stand604to be properly located under the body102. This can reduce damage to the body102(e.g., the floor pans or pinch welds) caused by improper placement of the vehicle stand604.

Of course, in some examples, rather than being stored in the propulsion control system616, the localization module806, drive unit data808, torque data810, vehicle support data812, and other functions, or portions thereof, can be located on another component, such as the central control or another remote server, for example, and accessed by the propulsion control system616via a communication network.

The propulsion control system616can also include one or more processors814, removable storage816, non-removable storage818, transceiver(s)820, output device(s)822, and input device(s)824. In some implementations, the processor(s)814can comprise a central processing unit (CPU), a graphics processing unit (GPU), or both a CPU and a GPU, or any other sort of processing unit, including, but not limited to ASICs, FPGAs, microcontrollers and the like. The processor(s)814can be responsible for running software on the propulsion control system616, including the OS804and other modules, and to interpret and send messages to the central control, if applicable. In some examples, the processor(s)814can also perform calculations and provide instructions based on the current localization data, torque data, etc.

The propulsion control system616can also include additional data storage devices (removable and/or non-removable) such as, for example, memory chips, magnetic disks, optical disks, or tape. Such additional storage is illustrated inFIG. 8by removable storage816and non-removable storage818. The removable storage816and non-removable storage818can store the various modules, programs, and algorithms for the OS804and other modules.

Non-transitory computer-readable media may include volatile and nonvolatile, removable and non-removable tangible, physical media implemented in technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. The memory802, removable storage816, and non-removable storage818are all examples of non-transitory computer-readable media. Non-transitory computer-readable media include, but are not limited to, RAM, ROM, electronically erasable programmable ROM (EEPROM), flash memory or other memory technology, compact disc ROM (CD-ROM), digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other tangible, physical medium which can be used to store the desired information and which can be accessed by the propulsion control system616. Any such non-transitory computer-readable media may be part of the propulsion control system616or may be a separate device (e.g., a jump drive) or a separate data or databank (e.g., at a central server).

In some implementations, the transceiver(s)820can include any sort of transceivers known in the art. The transceiver(s)820can include, for example, wireless modem(s) to facilitate wireless connectivity between the cart600and the torquing devices610, vehicle100, the Internet, and/or an intranet. Further, the transceiver(s)820may include a radio transceiver that performs the function of transmitting and receiving radio frequency communications via an antenna (e.g., cellular, Wi-Fi, or Bluetooth®). In some examples, the transceiver(s)820can also include wired transceivers to enable the cart600to establish communications between the cart600and the vehicle100via one or more docking pins608, for example, as mentioned above.

In some implementations, the output device(s)822can include any sort of output devices known in the art, such as the displays (e.g., a liquid crystal display (LCD), light emitting diode (LED) display, or thin film transistor (TFT) screen), a touchscreen display, lights, speakers, a vibrating mechanism, or a tactile feedback mechanism to provide interactive feedback to an operator, a repair technician, etc. In some examples, the output device(s)822can play various sounds related to whether the cart600is “docked” with the vehicle100, the distance between the cart600and the vehicle100, during loosening or tightening sequences, etc. When removing a drive unit104,106from a vehicle100, for example, the cart600may “beep” when reversing, similar to commercial and construction vehicles. Output device(s)822can also include ports for one or more peripheral devices, such as headphones, peripheral speakers, or a peripheral display to provide feedback to operators, service technicians, or assembly line workers, for example.

In various implementations, input device(s)824can include any sort of input devices known in the art. For example, input device(s)824may include a microphone, a keyboard/keypad/touchpad, a touch-sensitive display, a proximity sensor, gyroscope, accelerometer, altimeter, and other sensors. A keyboard/keypad may be a standard push button alphanumeric, multi-key keyboard (such as a conventional QWERTY keyboard), a touchscreen keyboard, or one or more other types of keys or buttons, and may also include a joystick, wheel, and/or designated navigation buttons, or the like. In some examples, the input device(s)824can also include communication ports to receive data from service technicians (e.g., for updates), external sensors, or cameras, among other things.

Example Clauses

A. A robotic cart comprising a drive system to move the robotic cart throughout an area, one or more transceivers to send and receive one or more wired and wireless transmissions, memory storing at least a localization module and torque data, one or more inputs to receive data from a user, and one or more processors in communication with at least the one or more transceivers, the memory, and the one or more inputs, the memory including computer executable instructions to cause the one or more processors to receive sensor data from one or more sensors disposed about a robotic cart, determine, using the sensor data, a pose of the robotic cart relative to a vehicle, plan a trajectory of the robotic cart based, at least in part, on the pose, the trajectory causing the robotic cart to align with one or more couplers of the vehicle, cause a drive unit of a robotic cart to move the robotic cart along the trajectory, send a first signal to torquing device on the robotic cart, the first signal causing a torquing device to rotate a drive interface in a first direction to remove a fastener from the vehicle, the fastener detachably coupling a subassembly to the vehicle, and move, using the drive unit, the robotic cart in a second direction away from the vehicle to remove the subassembly from the vehicle.

B. The robotic cart of paragraph A, wherein the sensor data comprises sensor data received from an environment proximate the vehicle and the robotic cart, the environment comprising one or more fiducials, and wherein the one or more fiducials comprise one or more artificial reality tags, bar codes, QR codes, or retroreflectors.

C. The robotic cart of paragraph A or B, further comprising a vehicle stand detachably coupled to the robotic cart, the computer executable instructions further causing the one or more processors to send a second signal to a latch detachably coupling the vehicle stand to the robotic cart, the second signal causing the latch to decouple the vehicle stand from the robotic cart, and send a third signal to cause a torquing device on the robotic cart to engage with a drive interface of a fastening system on a subassembly of the vehicle, wherein the vehicle stand of the robotic cart remains in place under a body of the vehicle to support the body with the subassembly removed.

D. The robotic cart of paragraph A, B, or C, the computer executable instructions further causing the one or more processors to send a fourth signal from the one or more processors to the vehicle stand to cause a portion of the vehicle stand to lower to a ground surface to support the body of the vehicle when the subassembly is removed.

E. The robotic cart of paragraph A, B, C, or D, the computer executable instructions further causing the one or more processors to send a second signal to the vehicle, the second signal causing the vehicle to alter a portion of a suspension of the vehicle to raise or lower the vehicle.

F. The robotic cart of paragraph A, B, C, D, or E, wherein rotating the drive interface with the torquing device comprises rotating a first driveshaft with a first torque device to remove a first fastener from a body of the vehicle, and rotating a second driveshaft a second torque device to remove a second fastener from the body of the vehicle.

G. A method comprising determining a first pose of a robotic cart based, at least in part, on sensor data received from one or more sensors disposed about the robotic cart, moving, using a drive unit, the robotic cart into a second pose relative to a vehicle, the second pose aligning a portion of a main body of the robotic cart with a vehicle stand disposed underneath a body of the vehicle, sending, using a transceiver of the robotic cart, a first signal to cause one or more latches to connect the vehicle stand to the robotic cart, sending, using the transceiver, a second signal to cause a torquing device on the robotic cart to rotate a drive interface of a fastening system of a subassembly of the vehicle in a first direction to tighten a fastener to detachably couple the subassembly to the vehicle, and moving, using the drive unit, the robotic cart in a second direction away from the vehicle.

H. The method of paragraph G, further comprising sending a third signal to cause a foot inside the vehicle stand to retract to lower the vehicle.

I. The method of paragraph G or H, wherein the sensor data comprises sensor data received from an environment proximate the vehicle and the robotic cart, the environment comprising one or more fiducials, and wherein the one or more fiducials comprise one or more artificial reality tags, bar codes, QR codes, or retroreflectors.

J. The method of paragraph G, H, or I, wherein rotating the drive interface with the torquing device comprises rotating an external driveshaft of the fastening system with a first torque device to tighten a first fastener to detachably couple the subassembly to the vehicle, and rotating an internal driveshaft of the fastening system with a second torque device to tighten a second fastener to detachably couple the subassembly to the vehicle.

K. The method of paragraph G, H, I, or J, wherein the first torque device tightens the first fastener, the second torque device tightens the second fastener, and the first torque is different than the second torque.

L. The method of paragraph G, H, I, J, or K, wherein the robotic cart moves at a first speed when the robotic cart is outside a first distance from the vehicle, and wherein the robotic cart moves at a second speed when the robotic cart is inside the first distance from the vehicle.

M. A robotic cart comprising an area for supporting a subassembly when the subassembly is removed from a vehicle, a drive system for moving the robotic cart throughout an environment, and a plurality of sensors to determine a pose of the robotic cart, and a torquing device, sized and shaped to engage with a fastening system of the subassembly of the vehicle, the torquing device rotating a driveshaft of the fastening system about a vertical axis, wherein rotating the driveshaft of the fastening system about the vertical axis causes a fastener of the subassembly to rotate about a horizontal axis, and wherein the fastener detachably couples the subassembly to the vehicle.

N. The robotic cart of paragraph M, wherein the torquing device includes a first torque device comprising a first drive interface configured to couple with a first driveshaft of the fastening system, and a second torque device, concentric to the first torque device, comprising a second drive interface configured to couple with a second driveshaft of the fastening system.

O. The robotic cart of paragraph M or N, wherein the first drive interface comprises a first external drive interface configured to interface with a first driveshaft of the fastening system, and wherein the second drive interface comprises a first internal drive interface or a second external drive interface to interface with a second driveshaft of the fastening system.

P. The robotic cart of paragraph M, N, or O, further comprising one or more couplers to couple with one or more pickup points of the subassembly.

Q. The robotic cart of paragraph M, N, O, or P, further comprising an upper stanchion comprising one or more couplers to couple with one or more additional pickup points of the subassembly.

R. The robotic cart of paragraph M, N, O, P, or Q, the upper stanchion comprising one or more actuators to move the upper stanchion between a lowered position and a raised position to support the subassembly.

S. The robotic cart of paragraph M, N, O, P, Q, or R, further comprising a vehicle stand, detachably coupled to the robotic cart, the vehicle stand including: one or more latches to releasable couple the vehicle stand to the robotic cart, one or more couplers to couple with one or more pickup points of the vehicle, and a foot to engage a body of the vehicle.

T. The robotic cart of paragraph M, N, O, P, Q, R, or S, the foot further comprising a jack to lift the body of the vehicle.