The chassis is arguably one of the most important parts of a racing car. It affects almost everything and the majority of a design time went into the critical design. First step was to get over all the rules to make sense of what is allowed and not. Create a simple dummy in solid works and make sure that you would fit into a car. Build an ergonomics jig with dimensions the same as chassis. Making sure all the other parts fit was mounting all of the parts in the chassis, which really takes patience, but we want to make sure that there are no clearance issue.
We can use a Finite Element Analysis to see how strong the car is, as well as add protection plates. Part of the dsign was how to actuall build the chassis. Put marking on drawings that are used to cut the tubes in chassis member cuts. The we need to know the "chassis member cuts". If multiple tubes are done at a single point they must be done in same order. We need a certain order where cuts are made.
You can also "stiffen" the chassis to make the car safer for the driver:
Then I need a stable or dimensionally accurate chassis table.
First cut is curring overall length and sticking the cutting drawings on each length. Next was cutting ends of the tube, with hole side and distance of hole, as well as the angle between them. The process of cutting the tubes took a very long time. Any tibe with a very shallow tool needs to be cut by hand through hand grinder, bench grinder, deburring tool. Taking eveything in place and after double checking everything, the weld is completed. Everything is then made on a chassis rig. The weld hoop had to be positioned at the right angle.
The pad had to be positioned at the right angle while temporary brace is attached to top holding it to the correct position. Reposition the chassis on the jig as we would need different angles when rotated.
Then the front members go on showing cockpit length. We can have brackets to allow bracing to be added in the chassis. Braces are really easy to get to position before welding. Anything attaching to the same longitudinal members have to be attached very early. Final members get inserted between the primary and secondary heads. I completed all the welds to improve the overall stiffness of the frame.
Main cockpit is now done and then you can jump in to see what it feels like. There are members that will allow holes where we insert the h-beam into the car. A nice flat surface place is ideal, but not necessary. We can build a chamber similar to the size of the floor in the chassis.
Chassis is a skeleton the supports things. There are longitudinal frames which are connected to cross frames inside of the car, which can also be named as the cross members. These cross members are connected through boltin to good stability and strength in frame. 5-6 cross members are usually used in the same frame/stability. Sometimes these cross frames are provided in diagonal cross bracing.
Torsional rigidity test carried out on chassis frame to sustain load conditions such as accidents & impacts.
The longitudinal members are up straight front and rear which has an axle and pringing, and the front is provided for the suspension.
Brackets are provided for the mounting to the chassis, to support and mount for regular suspension springs, engine blocks, and auxillary.
The front axle is the front overhang, while the rear axle is the rear overhang. A typical chassis frame section can be represented with longitudinal members, bolted by 5-6 cross members held by bolts. Diagonal Cross Bracing is provided for more torsional rigidity.
Longitudinal members are upswept through front and rear and kept frame height load and frame tappers from rear to front. Brackets are also provided to support and mount different parts. Everything else is mounted by means of rubber blocks, helping prevent vehicle vibrations. We can compare geometries of different chassis shapes. Te first is called a ladder chassis. This is exactly what you find on heavy-duty trucks. These square are laminated together. The main advantage is it is very strong. Torsional rigidity refers to a components resistance to being twisted in a particular direction.
The next chassis is a 4-cube designs with 4 cubest connecting by cross members with divers accross the end since now you have a lot of room for racecar draiver, where everything can be enclose inside of a box structure. (100% Rigidity)
The next thing is a space frame, which it means that all the structural loads are carried in tension or compression, not in binding. You need to turn a structure into triangles to put things in compression or tension. (230% Rigidity)
(1800% rigidity)
Here we have 3 structures then. The thing a structure has the most toruble with is torsional rigidity. Everything has a dangling cord. We need to measure deflection, with a dial indicator to see how much deflection that something has. Dropping nuts on a spindle with a wood model can also get you to get a deflection with the same moment arm. Structural rigidity comes from the geometry for the materials and lighter is ually better because materials cost money. Triangles are an engineers best friend.
Weld everything in order to reduce the number of distortion. We also need a mount to have a crumple zone which will take the chassis if I have an accident. We should also adda. beacon detecting whether the car has passed the start/finish line. Use a small sand blasting cabinet to clean things up. Finally we give the paint to finish the job.
To connect the engine and gearbox, work for most of the day to try to cut out degrees of freedom one by one, to then get one measurement at a time. Lower members, upper members, lower triangular members, and finally the other members after this. Have a used engine vs a new engine as experimentation and testing first. Connect gearbox and engine together, then bolt them into the chassis, and move the braces/engine parts/intake manifold. Try to see where you can provide small amounts of extra support. From here it's onto smaller mounts and brackets. First put the front damper mount to proved a standoff to which the damp can be bolted. So general chassis first, then mounting.
Having laser-cut parts makes fabricating easy. Once assembly is welded, place it in the car and weld it wound the perimeter. So weld once for assembly, once for perimeter. Mount the steering wheel, dashboard, pedals, floor, and the one of the last mount is for the rear to the chair. You can tie it into the transmission subframe. Finally, seatbelt mounts. Need6 mounts all into the chairs. You might have to do holes in chassis. You need to sandblast the chassis, and gets everywhere, and the nozzles would wear out, and then paint the chassis with a couple of coats. Finally the chassis is complete.
Longitudinal members are also called side members. Cross members are between those side members. To turn the front members, make the frame narrower in the front. We need several cross members, to make the frame strong and rigid. We put in a cross member in order to reduce torsional rigidity. Letter Y will get force to transfer to the center of the frame. Then we can put in letter K.
For the most fragile aprts, we use a steel girder and a heavy steel plate. We add heavy steel plate to give us extra strength. We also have the hump so we give it a reinforcement as well (2 steel). A Knee action makes the front end of the car as ridig as possible. Rivets screw the car. Then we have 219 tough rivets to hold car together.
Rivets that won't shrink. Strong heavy side members for support. Cross members for rigidity. Center braces for strength. Heavy reinforcement at points of greatest strain, and strong front to hold the knee-action wheels.
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