Hydraulic Jacks for a robot cart?

Does anyone have any recommendations as to a lift jack that we can mount on a robot cart to bring a table with a robot on it to working height? We are going to be building one on the offseason.

Many teams buy off the shelf carts with a hydraulic lift. Similar ones to this

This season my team remade our robot cart to add a lift on it. We somehow were able to pull it off in a week (I’ll post pictures later), while also finishing our practice bot. We purchased a Harbor Freight 500 lb (I believe) lift, that we heavily modified to fit our needs better. We essentially flipped it backwards so the foot pump was off the front, cut the caster mounts to go onto our frame, and relocated the lowering mechanism to the right side. Once I get to a desktop rather than my phone, I’ll include photos. The HF cart seemed to work well, my only complaint is that it takes a ton of pumps to get up high enough. The lift is not useful we felt like in a year where we have a short robot, (2017, 2016), and only useful for when you have to work on high parts or a robot, and low on a regular basis.

We use this one from our local Northern Tool:

https://www.northerntool.com/shop/tools/product_200696309_200696309

My team originally wanted to make a hydraulic jack cart this year, but we ran out of time to implement it properly. Honestly, I’m much happier with what we did instead.

Our final cart design ended with two “levels.” The top level is made of two sets of hinged profiles (one of each side of the cart). Each side has one tube the length of the cart (“the rail”) attached with a hinge to the handle, with another tube (“the leg”) attached to the other end of rail with a hinge. The bottom of the legs sit between two small pieces of tube (“stops”) on the floor of the cart to keep them from slipping out. When we want the robot up high, the robot site on the rails. When we want the robot closer to the ground, we can fold the rails and legs up to the handle and sit the robot on the floor of the cart. I attached an MSPaint sketch to try to explain it better.

This cart gives the advantage of a hydraulic lift cart (i.e. having two possible robot heights), without having to deal with hydraulics or lifts. It was extremely easy to assemble, only needed some spare tubing, off-the-shelf hinges, and hardware store brackets. I’d recommend this cart type to any team looking for a new cart.

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One thing to consider is the added weight, particularly if you don’t have a team trailer with a ramp that you can just wheel everything onto. Our carts and robots and all of our pit gear routinely gets lifted into and out of the bottom of coach buses, the backs of mentor SUVs and minivans, into pickup truck beds, up and down curbs, rolled down the street, etc. If there’s anything we have learned it’s “the lighter, the better” (and also “many student hands make light work” :D)

We bought one of those for this year. Warning to anyone looking to buy the same thing, it is HEAVY and difficult to steer compared to carts we’ve used in the past. It was also narrower than the width between our robot’s wheels, so we had some issues with seating, but that’s a very robot-specific problem and YMMV (we also should have addressed that issue before competitions and didn’t). Other than that it did do the job well.

That is not a bug, it’s a feature. We have always designed our carts so that the wheels are free to turn. That enables pit testing without being worried that the robot is going to take off.