Have they stated what the drones would even be for? Could they just be for path finding to make life easy on the rover?It seems an awful lot of risk to have fetch drones, this is brand new tech in the critical path for MSR. Fetch drones don't seem to make sense.
Does a fetch helicopter really reduce risk? The other alternative is to leave the samples on the rover and hope that it lasts for ten years plus. Perseverance seems to be very healthy. Curiosity is still running. They are nuclear powered so you don't have to worry about dust storms. The odds are very good that Perseverance will last as long as it needs to and be able to deliver samples directly to the MAV. If Mars Sample Return fails it will probably be because of something that happens after MAV is launched. The risk of rover failure could be managed by giving the MAV lander the capability to collect a soil sample and return that if the rover doesn't deliver.Deleting the fetch rovers and helicopters reduces cost and complexity, while adding some risk.
No plan has the samples remaining on the rover indefinately.
Mars Ascent Vehicle.
Quote from: Blackstar on 07/14/2022 06:12 pmMars Ascent Vehicle.Much appreciate the human scale.
Quote from: vjkane on 07/14/2022 10:08 pmQuote from: Blackstar on 07/14/2022 06:12 pmMars Ascent Vehicle.Much appreciate the human scale.Meenakshi (Mini) Wadhwa, Mars Sample Return Principal Scientist at ASU’s School of Earth and Space Exploration.
Quote from: Blackstar on 07/14/2022 10:23 pmQuote from: vjkane on 07/14/2022 10:08 pmQuote from: Blackstar on 07/14/2022 06:12 pmMars Ascent Vehicle.Much appreciate the human scale.Meenakshi (Mini) Wadhwa, Mars Sample Return Principal Scientist at ASU’s School of Earth and Space Exploration.So the MAV is about 2.5 Mini's. That's larger than I'd been mentally thinking.
Estimating that is a 30 inch diameter rocket motor for the 1st stage of the MAV using the Mini scale.
Rather confused/confusing article from the BBC https://www.bbc.com/news/science-environment-62234196"US and Europe are remodelling their plans to bring rock samples back from Mars, for study in Earth laboratories.They hope to simplify the process, cut risk and cost using helicopters instead of a British-built "fetch rover"."But..."American and European space agencies are now confident Perseverance can do this itself."
Quote from: Dalhousie on 07/21/2022 05:30 amRather confused/confusing article from the BBC https://www.bbc.com/news/science-environment-62234196"US and Europe are remodelling their plans to bring rock samples back from Mars, for study in Earth laboratories.They hope to simplify the process, cut risk and cost using helicopters instead of a British-built "fetch rover"."But..."American and European space agencies are now confident Perseverance can do this itself."Multiple options: 1. Fetch Rover travels to dropped sample caches, picks them up with an arm, then moves them to the MAV. 1.1 - If Perseverance fails, dropped cache tubes are still available. 1.2 - If the Fetch Rover fails or is unavailable, Perseverance can use the duplicate tubes carried on-board and travel to the MAV itself2. Fetch Helicopter travels to dropped sample caches, picks them up, then flies them to the MAV.2.1 - If Perseverance fails, dropped cache tubes are still available.2.2 - If the Fetch Helicopter fails or is unavailable, Perseverance can use the duplicate tubes carried on-board and travel to the MAV itself3. Perseverance can use the duplicate tubes carried on-board and travel to the MAV itself in the absence of a fetch rover or fetch helicopter.3.1 - If Perseverance fails, all samples are unavailable. Implementing more than one option means a failure does not doom the entire sample return mission architecture.
There seems to be an assumption that the functioning rover already on the surface is more likely to fail than an unbuilt unlaunched and unlanded rover. It would have been lower risk, in my opinion, to keep all of the samples on the rover and drive it to the return vehicle landing site.