Why does curiosity move so slowly

However, it had far surpassed its expected lifetime. Both rovers exceeded their planned day mission lifetimes by many years. Spirit lasted 20 times longer than its original design until its final communication to Earth on March 22, Opportunity continues to operate more than a decade after launch. Begin typing your search term above and press enter to search. Press ESC to cancel.

This boundary gives the flight team a high level of confidence that the rover will avoid driving on or over the target or into dangerous terrain that was out of the line of sight from the Navcams, and also prevents the rover from spending too much time getting to an "exact" location, since it might have slipped a little anyway. The "go to waypoint" command includes time and distance limits that protect both against missing the target and also against being diverted too far from the goal by obstacles.

For example, if the target is 60 centimeters 2 feet away on flat surface, and the rover is still moving after 2 minutes 1 minute longer than the trip should have taken , something most likely is wrong and the rover will stop. Fixed time limits are also given to the rover wheels for each "step" that the rover takes when going to a waypoint.

If the rover were to get stuck on a single step, this limit would prevent it from running the wheel motors until the overall timeout for the "go to waypoint" command expired which could potentially be very long, perhaps tens of minutes to hours for far field traverses.

While the rover is stopped, a pair of images from the front and occasionally also the rear Hazcams is captured and processed, into a set of x,y,z coordinate points in front of the rover. This resulting map of points is processed into a set of terrain features steps, slopes, roughness which serve as a three-dimensional model of the actual terrain in front of the vehicle.

The Sojourner Rover on the Pathfinder mission in took 20 separate measurements for every step. The Mars Exploration Rovers take between 6, to 10, points of measurements per step. This model is used to determine if the terrain features represent obstacles for the rover for instance, a feature with height of 30 centimeters 12 inches or greater is considered an obstacle. A small number of short potential paths in the direction to the destination are checked within this model and a safe path avoiding obstacles is chosen.

As new terrain models are acquired, they are organized into a "world" model with the rover at the center of approximately a 10m-bym area. Due to the possibility of wheel slippage, the rover is programmed to only remember a small map around it in order to remain accurate about the surrounding obstacles.

Information about the terrain surrounding the rover beyond the 10m-bym area therefore must be deleted every additional 5 meters driven. So, as the rover goes forward roughly six times the length of its own body , it forgets where it has been. Some of this map data is stored elsewhere onboard the rover and some is sent back to Earth to help build a master map; however, there is a limit to how much data can be sent back to Earth.

For further information about data flow to and from the rover, please see Rover Communications. Once constructed, the map helps the rover select safe movements to the destination and prevents the rover from encountering obstacles already avoided during prior segments of the drive.

What we really need are motors and gear boxes that can operate at ambient Mars temperatures. The MSL project tried to develop those, but ran into problems and fell back to the existing technology.

Show 3 more comments. Ian It's like my post, but put in scientific terms. I would delete my post in favor of this, but the reputation at this point is too tempting :D I'm certain though, this would get higher points in the end. You have a nice on-topic photo for the illiterates. The amount of power you need to do a task is inversely proportional to the time it takes to do that task.

I think it is well known that doing something faster requires more power, otherwise you could do everything infinitely fast at no cost. Computation Speed. The statement about power above is not limited to movements. It is also true for computation. Have you noticed when your laptop is on power-saving mode, it runs slower?

With processors, if you compute something twice as fast, you need four times more energy to do it. As a result, most probably, the CPU of mars rovers are also not working at a high speed. Therefore, if the rover needs time to process something before moving on for example images of the environment , it needs to move slower so it would receive data at a slower rate. Slow enough so that it can process them. I believe I don't need to give you formulas for this phenomenon: Simply put, the slower you go, the smaller the chance of lifting off over a ridge and possibly losing your stability when you land.

If you go at a reasonably slow speed, you wouldn't have any trouble steering. On the other hand, at high speeds, you need larger curvature to turn, as well as more pressure on the wheels on the outer side. Shahbaz Shahbaz 3, 1 1 gold badge 18 18 silver badges 36 36 bronze badges.

Curiosity weights almost a ton similar to a subcompact , but it's power source only produces W of power. If all of the power was available for the drive train that would only be. Getting enough power for a high speed, long duration, rover isn't possible with current technology so all of the proposed missions were designed for a slow rate of travel and an in depth study of a relatively small area.

Doing something twice as fast requires twice the force, but the same amount of energy. Unless the limiting factor is something that scales with the square by itself like fluid resistance scales with the square of your speed , but to apply that to the Mars rover you'd have to explain what specific limiting factors there are. Show 8 more comments. I find myself treating the experience like a video game: starting out cautiously with a few gentle turns, before commanding the car-sized rover to cross some sizable boulders.

Thankfully the real rover, some million kilometers million miles away on the Red Planet, is in safer hands. But a Mars day is 40 minutes longer than an Earth day so you get progressively out of synch, so the time I arrive at work changes by an hour every day. During the Martian night, dozens of scientists, including Gupta, anaylse the images and data coming back from the Red Planet and discuss what they want to do next.

Curiosity is the fourth rover since the Pathfinder mission Nasa has run on Mars in recent years, and the procedures have got better with every mission. Armed with 3D images from its navigation cameras, the drivers work through the Martian night to map out the best, smoothest, route to the next destination. They factor in any stops along the way, to take pictures or operate an instrument, and run a simulation of the journey to double-check they have got it right.