Building EXP Robot Lift Systems

Lifts are assembled to lift other manipulators vertically or to lift the robot off the ground. Lifts are usually activated using motors attached to a gear system or sprocket/chain system and are usually attached to the robot chassis. Scissor lifts and cascading lifts frequently use rubber bands or latex tubing to assist with the lifting.

Lifts can be assembled using a variety of the contents included in the EXP Kit. Lifts are capable of reaching extreme heights. However, they require a great deal of planning and time to assemble. Four types of common lifts will be explained in this article.

Scissor Lifts

Scissor lifts are assembled by creating a pivot point at the midsection of two structural pieces of metal which are crossed. Typically, the end of one piece of metal is fixed to a pivot point on the chassis and the end of the other piece of metal can slide towards the first end across the chassis. This closes the scissor, raising up the two pieces. These lifts are nearly always assembled as pairs to equalize the forces on the lift. There is usually a platform on the top of the lift which is attached in the same manner as the bottom. One side is fixed to a pivot point and the other side can slide. A scissor lift can be activated by using an 84T High Strength Gear mounted to one piece of the metal at the pivot point between the two pieces of structural metal. This gear can be driven by a 12T High Strength Gear attached to a motor. The 12T Gear drives the 84T Gear lifting the assembly. Another method to elevate the scissor lift uses a spur gear on a motor and the Rack Gear with the design of the Linear Slide lift to pull one side of the scissors, sliding it towards the pivot side. Scissor lifts may require extensive cross supports to provide stability. The more scissor sections assembled on top of each other, the higher the lift can reach. However, it takes more torque to lift them and it becomes more difficult to stabilize the lift. The lower a scissor lift compresses, the more difficult it is to raise it. Due to the many linkages necessary within a scissor lift and the variety of forces acting on the lift, it can be among the most difficult of the manipulators to assemble as an effective functioning system.

Linear Slides

Linear Slides are assembled using the Rack and spur Gears found within the EXP Kit. A make-shift Linear Motion Kit has to be built with EXP parts in order to use this design efficiently. Rack Gears are mounted to a Flat Beam, and standoffs as well as snap-on spacers attach an additional Flat Beam behind the first. Linkage Beams are then used to slide the length of the lift. Lastly, a motor is assembled in the make-shift Rack Gearbox Bracket with a spur gear on its shaft. This will allow the rack bracket assembly to travel up and down the linear slide track as the spur gear drives over the Rack Gear. The Flat Beams are usually attached to the chassis and a manipulator, additional rack track, or platform can be attached to the Rack Bracket.

Telescoping Lifts

Telescoping lifts are assembled using nested pairs of C-Channels. Telescoping lifts are similar to cascading lifts in that they both use sliding nested C-Channels. The lift works by placing a pinned chain linkage at the top of the C-Channel assembly. The base C-Channel is attached to the chassis. A motor is attached to the first stage of the lift which powers the chain, and due to the pinned linkage the resultant force drives the lift upwards. Telescoping Lifts also frequently use winch and pulley systems, but due to kit contents this design is closest to its real-life counterpart. This assembly can be repeated allowing the lift to quickly reach extreme heights.

Cascading Lifts

Cascading lifts are similar to telescoping lifts in that the EXP version both uses chains and sliding nested C-Channels. Cascading lifts are sometimes called chain lifts. These lifts are nearly always assembled as pairs to equalize the forces on the lift. Cascading lifts are assembled by nesting pairs C-Channel together and attaching one set of C-Channel to the chassis with a sprocket and chain system between the pair of C-Channels. The next pair of C-Channels are attached to the chain and sprocket system. As one or more motors spin the chain and sprockets, the second pair of C-Channels slide up the first pair due to a pinned chain linkage.
This assembly can be repeated to reach extreme heights. Spacers are necessary to keep the C-Channel sections nested together and allow them to slide up and down one another.

Note: Another option for lifting objects are robotic arms.

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